1 /* 2 * AppArmor security module 3 * 4 * This file contains AppArmor policy attachment and domain transitions 5 * 6 * Copyright (C) 2002-2008 Novell/SUSE 7 * Copyright 2009-2010 Canonical Ltd. 8 * 9 * This program is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU General Public License as 11 * published by the Free Software Foundation, version 2 of the 12 * License. 13 */ 14 15 #include <linux/errno.h> 16 #include <linux/fdtable.h> 17 #include <linux/file.h> 18 #include <linux/mount.h> 19 #include <linux/syscalls.h> 20 #include <linux/tracehook.h> 21 #include <linux/personality.h> 22 23 #include "include/audit.h" 24 #include "include/apparmorfs.h" 25 #include "include/context.h" 26 #include "include/domain.h" 27 #include "include/file.h" 28 #include "include/ipc.h" 29 #include "include/match.h" 30 #include "include/path.h" 31 #include "include/policy.h" 32 33 /** 34 * aa_free_domain_entries - free entries in a domain table 35 * @domain: the domain table to free (MAYBE NULL) 36 */ 37 void aa_free_domain_entries(struct aa_domain *domain) 38 { 39 int i; 40 if (domain) { 41 if (!domain->table) 42 return; 43 44 for (i = 0; i < domain->size; i++) 45 kzfree(domain->table[i]); 46 kzfree(domain->table); 47 domain->table = NULL; 48 } 49 } 50 51 /** 52 * may_change_ptraced_domain - check if can change profile on ptraced task 53 * @to_profile: profile to change to (NOT NULL) 54 * 55 * Check if current is ptraced and if so if the tracing task is allowed 56 * to trace the new domain 57 * 58 * Returns: %0 or error if change not allowed 59 */ 60 static int may_change_ptraced_domain(struct aa_profile *to_profile) 61 { 62 struct task_struct *tracer; 63 struct aa_profile *tracerp = NULL; 64 int error = 0; 65 66 rcu_read_lock(); 67 tracer = ptrace_parent(current); 68 if (tracer) 69 /* released below */ 70 tracerp = aa_get_task_profile(tracer); 71 72 /* not ptraced */ 73 if (!tracer || unconfined(tracerp)) 74 goto out; 75 76 error = aa_may_ptrace(tracerp, to_profile, PTRACE_MODE_ATTACH); 77 78 out: 79 rcu_read_unlock(); 80 aa_put_profile(tracerp); 81 82 return error; 83 } 84 85 /** 86 * change_profile_perms - find permissions for change_profile 87 * @profile: the current profile (NOT NULL) 88 * @ns: the namespace being switched to (NOT NULL) 89 * @name: the name of the profile to change to (NOT NULL) 90 * @request: requested perms 91 * @start: state to start matching in 92 * 93 * Returns: permission set 94 */ 95 static struct file_perms change_profile_perms(struct aa_profile *profile, 96 struct aa_namespace *ns, 97 const char *name, u32 request, 98 unsigned int start) 99 { 100 struct file_perms perms; 101 struct path_cond cond = { }; 102 unsigned int state; 103 104 if (unconfined(profile)) { 105 perms.allow = AA_MAY_CHANGE_PROFILE | AA_MAY_ONEXEC; 106 perms.audit = perms.quiet = perms.kill = 0; 107 return perms; 108 } else if (!profile->file.dfa) { 109 return nullperms; 110 } else if ((ns == profile->ns)) { 111 /* try matching against rules with out namespace prepended */ 112 aa_str_perms(profile->file.dfa, start, name, &cond, &perms); 113 if (COMBINED_PERM_MASK(perms) & request) 114 return perms; 115 } 116 117 /* try matching with namespace name and then profile */ 118 state = aa_dfa_match(profile->file.dfa, start, ns->base.name); 119 state = aa_dfa_match_len(profile->file.dfa, state, ":", 1); 120 aa_str_perms(profile->file.dfa, state, name, &cond, &perms); 121 122 return perms; 123 } 124 125 /** 126 * __attach_match_ - find an attachment match 127 * @name - to match against (NOT NULL) 128 * @head - profile list to walk (NOT NULL) 129 * 130 * Do a linear search on the profiles in the list. There is a matching 131 * preference where an exact match is preferred over a name which uses 132 * expressions to match, and matching expressions with the greatest 133 * xmatch_len are preferred. 134 * 135 * Requires: @head not be shared or have appropriate locks held 136 * 137 * Returns: profile or NULL if no match found 138 */ 139 static struct aa_profile *__attach_match(const char *name, 140 struct list_head *head) 141 { 142 int len = 0; 143 struct aa_profile *profile, *candidate = NULL; 144 145 list_for_each_entry_rcu(profile, head, base.list) { 146 if (profile->flags & PFLAG_NULL) 147 continue; 148 if (profile->xmatch && profile->xmatch_len > len) { 149 unsigned int state = aa_dfa_match(profile->xmatch, 150 DFA_START, name); 151 u32 perm = dfa_user_allow(profile->xmatch, state); 152 /* any accepting state means a valid match. */ 153 if (perm & MAY_EXEC) { 154 candidate = profile; 155 len = profile->xmatch_len; 156 } 157 } else if (!strcmp(profile->base.name, name)) 158 /* exact non-re match, no more searching required */ 159 return profile; 160 } 161 162 return candidate; 163 } 164 165 /** 166 * find_attach - do attachment search for unconfined processes 167 * @ns: the current namespace (NOT NULL) 168 * @list: list to search (NOT NULL) 169 * @name: the executable name to match against (NOT NULL) 170 * 171 * Returns: profile or NULL if no match found 172 */ 173 static struct aa_profile *find_attach(struct aa_namespace *ns, 174 struct list_head *list, const char *name) 175 { 176 struct aa_profile *profile; 177 178 rcu_read_lock(); 179 profile = aa_get_profile(__attach_match(name, list)); 180 rcu_read_unlock(); 181 182 return profile; 183 } 184 185 /** 186 * separate_fqname - separate the namespace and profile names 187 * @fqname: the fqname name to split (NOT NULL) 188 * @ns_name: the namespace name if it exists (NOT NULL) 189 * 190 * This is the xtable equivalent routine of aa_split_fqname. It finds the 191 * split in an xtable fqname which contains an embedded \0 instead of a : 192 * if a namespace is specified. This is done so the xtable is constant and 193 * isn't re-split on every lookup. 194 * 195 * Either the profile or namespace name may be optional but if the namespace 196 * is specified the profile name termination must be present. This results 197 * in the following possible encodings: 198 * profile_name\0 199 * :ns_name\0profile_name\0 200 * :ns_name\0\0 201 * 202 * NOTE: the xtable fqname is pre-validated at load time in unpack_trans_table 203 * 204 * Returns: profile name if it is specified else NULL 205 */ 206 static const char *separate_fqname(const char *fqname, const char **ns_name) 207 { 208 const char *name; 209 210 if (fqname[0] == ':') { 211 /* In this case there is guaranteed to be two \0 terminators 212 * in the string. They are verified at load time by 213 * by unpack_trans_table 214 */ 215 *ns_name = fqname + 1; /* skip : */ 216 name = *ns_name + strlen(*ns_name) + 1; 217 if (!*name) 218 name = NULL; 219 } else { 220 *ns_name = NULL; 221 name = fqname; 222 } 223 224 return name; 225 } 226 227 static const char *next_name(int xtype, const char *name) 228 { 229 return NULL; 230 } 231 232 /** 233 * x_table_lookup - lookup an x transition name via transition table 234 * @profile: current profile (NOT NULL) 235 * @xindex: index into x transition table 236 * 237 * Returns: refcounted profile, or NULL on failure (MAYBE NULL) 238 */ 239 static struct aa_profile *x_table_lookup(struct aa_profile *profile, u32 xindex) 240 { 241 struct aa_profile *new_profile = NULL; 242 struct aa_namespace *ns = profile->ns; 243 u32 xtype = xindex & AA_X_TYPE_MASK; 244 int index = xindex & AA_X_INDEX_MASK; 245 const char *name; 246 247 /* index is guaranteed to be in range, validated at load time */ 248 for (name = profile->file.trans.table[index]; !new_profile && name; 249 name = next_name(xtype, name)) { 250 struct aa_namespace *new_ns; 251 const char *xname = NULL; 252 253 new_ns = NULL; 254 if (xindex & AA_X_CHILD) { 255 /* release by caller */ 256 new_profile = aa_find_child(profile, name); 257 continue; 258 } else if (*name == ':') { 259 /* switching namespace */ 260 const char *ns_name; 261 xname = name = separate_fqname(name, &ns_name); 262 if (!xname) 263 /* no name so use profile name */ 264 xname = profile->base.hname; 265 if (*ns_name == '@') { 266 /* TODO: variable support */ 267 ; 268 } 269 /* released below */ 270 new_ns = aa_find_namespace(ns, ns_name); 271 if (!new_ns) 272 continue; 273 } else if (*name == '@') { 274 /* TODO: variable support */ 275 continue; 276 } else { 277 /* basic namespace lookup */ 278 xname = name; 279 } 280 281 /* released by caller */ 282 new_profile = aa_lookup_profile(new_ns ? new_ns : ns, xname); 283 aa_put_namespace(new_ns); 284 } 285 286 /* released by caller */ 287 return new_profile; 288 } 289 290 /** 291 * x_to_profile - get target profile for a given xindex 292 * @profile: current profile (NOT NULL) 293 * @name: name to lookup (NOT NULL) 294 * @xindex: index into x transition table 295 * 296 * find profile for a transition index 297 * 298 * Returns: refcounted profile or NULL if not found available 299 */ 300 static struct aa_profile *x_to_profile(struct aa_profile *profile, 301 const char *name, u32 xindex) 302 { 303 struct aa_profile *new_profile = NULL; 304 struct aa_namespace *ns = profile->ns; 305 u32 xtype = xindex & AA_X_TYPE_MASK; 306 307 switch (xtype) { 308 case AA_X_NONE: 309 /* fail exec unless ix || ux fallback - handled by caller */ 310 return NULL; 311 case AA_X_NAME: 312 if (xindex & AA_X_CHILD) 313 /* released by caller */ 314 new_profile = find_attach(ns, &profile->base.profiles, 315 name); 316 else 317 /* released by caller */ 318 new_profile = find_attach(ns, &ns->base.profiles, 319 name); 320 break; 321 case AA_X_TABLE: 322 /* released by caller */ 323 new_profile = x_table_lookup(profile, xindex); 324 break; 325 } 326 327 /* released by caller */ 328 return new_profile; 329 } 330 331 /** 332 * apparmor_bprm_set_creds - set the new creds on the bprm struct 333 * @bprm: binprm for the exec (NOT NULL) 334 * 335 * Returns: %0 or error on failure 336 */ 337 int apparmor_bprm_set_creds(struct linux_binprm *bprm) 338 { 339 struct aa_task_cxt *cxt; 340 struct aa_profile *profile, *new_profile = NULL; 341 struct aa_namespace *ns; 342 char *buffer = NULL; 343 unsigned int state; 344 struct file_perms perms = {}; 345 struct path_cond cond = { 346 file_inode(bprm->file)->i_uid, 347 file_inode(bprm->file)->i_mode 348 }; 349 const char *name = NULL, *info = NULL; 350 int error = 0; 351 352 if (bprm->cred_prepared) 353 return 0; 354 355 cxt = cred_cxt(bprm->cred); 356 BUG_ON(!cxt); 357 358 profile = aa_get_newest_profile(cxt->profile); 359 /* 360 * get the namespace from the replacement profile as replacement 361 * can change the namespace 362 */ 363 ns = profile->ns; 364 state = profile->file.start; 365 366 /* buffer freed below, name is pointer into buffer */ 367 error = aa_path_name(&bprm->file->f_path, profile->path_flags, &buffer, 368 &name, &info); 369 if (error) { 370 if (unconfined(profile) || 371 (profile->flags & PFLAG_IX_ON_NAME_ERROR)) 372 error = 0; 373 name = bprm->filename; 374 goto audit; 375 } 376 377 /* Test for onexec first as onexec directives override other 378 * x transitions. 379 */ 380 if (unconfined(profile)) { 381 /* unconfined task */ 382 if (cxt->onexec) 383 /* change_profile on exec already been granted */ 384 new_profile = aa_get_profile(cxt->onexec); 385 else 386 new_profile = find_attach(ns, &ns->base.profiles, name); 387 if (!new_profile) 388 goto cleanup; 389 /* 390 * NOTE: Domain transitions from unconfined are allowed 391 * even when no_new_privs is set because this aways results 392 * in a further reduction of permissions. 393 */ 394 goto apply; 395 } 396 397 /* find exec permissions for name */ 398 state = aa_str_perms(profile->file.dfa, state, name, &cond, &perms); 399 if (cxt->onexec) { 400 struct file_perms cp; 401 info = "change_profile onexec"; 402 new_profile = aa_get_newest_profile(cxt->onexec); 403 if (!(perms.allow & AA_MAY_ONEXEC)) 404 goto audit; 405 406 /* test if this exec can be paired with change_profile onexec. 407 * onexec permission is linked to exec with a standard pairing 408 * exec\0change_profile 409 */ 410 state = aa_dfa_null_transition(profile->file.dfa, state); 411 cp = change_profile_perms(profile, cxt->onexec->ns, 412 cxt->onexec->base.name, 413 AA_MAY_ONEXEC, state); 414 415 if (!(cp.allow & AA_MAY_ONEXEC)) 416 goto audit; 417 goto apply; 418 } 419 420 if (perms.allow & MAY_EXEC) { 421 /* exec permission determine how to transition */ 422 new_profile = x_to_profile(profile, name, perms.xindex); 423 if (!new_profile) { 424 if (perms.xindex & AA_X_INHERIT) { 425 /* (p|c|n)ix - don't change profile but do 426 * use the newest version, which was picked 427 * up above when getting profile 428 */ 429 info = "ix fallback"; 430 new_profile = aa_get_profile(profile); 431 goto x_clear; 432 } else if (perms.xindex & AA_X_UNCONFINED) { 433 new_profile = aa_get_newest_profile(ns->unconfined); 434 info = "ux fallback"; 435 } else { 436 error = -EACCES; 437 info = "profile not found"; 438 /* remove MAY_EXEC to audit as failure */ 439 perms.allow &= ~MAY_EXEC; 440 } 441 } 442 } else if (COMPLAIN_MODE(profile)) { 443 /* no exec permission - are we in learning mode */ 444 new_profile = aa_new_null_profile(profile, 0); 445 if (!new_profile) { 446 error = -ENOMEM; 447 info = "could not create null profile"; 448 } else 449 error = -EACCES; 450 perms.xindex |= AA_X_UNSAFE; 451 } else 452 /* fail exec */ 453 error = -EACCES; 454 455 /* 456 * Policy has specified a domain transition, if no_new_privs then 457 * fail the exec. 458 */ 459 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) { 460 error = -EPERM; 461 goto cleanup; 462 } 463 464 if (!new_profile) 465 goto audit; 466 467 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 468 /* FIXME: currently don't mediate shared state */ 469 ; 470 } 471 472 if (bprm->unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 473 error = may_change_ptraced_domain(new_profile); 474 if (error) 475 goto audit; 476 } 477 478 /* Determine if secure exec is needed. 479 * Can be at this point for the following reasons: 480 * 1. unconfined switching to confined 481 * 2. confined switching to different confinement 482 * 3. confined switching to unconfined 483 * 484 * Cases 2 and 3 are marked as requiring secure exec 485 * (unless policy specified "unsafe exec") 486 * 487 * bprm->unsafe is used to cache the AA_X_UNSAFE permission 488 * to avoid having to recompute in secureexec 489 */ 490 if (!(perms.xindex & AA_X_UNSAFE)) { 491 AA_DEBUG("scrubbing environment variables for %s profile=%s\n", 492 name, new_profile->base.hname); 493 bprm->unsafe |= AA_SECURE_X_NEEDED; 494 } 495 apply: 496 /* when transitioning profiles clear unsafe personality bits */ 497 bprm->per_clear |= PER_CLEAR_ON_SETID; 498 499 x_clear: 500 aa_put_profile(cxt->profile); 501 /* transfer new profile reference will be released when cxt is freed */ 502 cxt->profile = new_profile; 503 new_profile = NULL; 504 505 /* clear out all temporary/transitional state from the context */ 506 aa_clear_task_cxt_trans(cxt); 507 508 audit: 509 error = aa_audit_file(profile, &perms, GFP_KERNEL, OP_EXEC, MAY_EXEC, 510 name, 511 new_profile ? new_profile->base.hname : NULL, 512 cond.uid, info, error); 513 514 cleanup: 515 aa_put_profile(new_profile); 516 aa_put_profile(profile); 517 kfree(buffer); 518 519 return error; 520 } 521 522 /** 523 * apparmor_bprm_secureexec - determine if secureexec is needed 524 * @bprm: binprm for exec (NOT NULL) 525 * 526 * Returns: %1 if secureexec is needed else %0 527 */ 528 int apparmor_bprm_secureexec(struct linux_binprm *bprm) 529 { 530 /* the decision to use secure exec is computed in set_creds 531 * and stored in bprm->unsafe. 532 */ 533 if (bprm->unsafe & AA_SECURE_X_NEEDED) 534 return 1; 535 536 return 0; 537 } 538 539 /** 540 * apparmor_bprm_committing_creds - do task cleanup on committing new creds 541 * @bprm: binprm for the exec (NOT NULL) 542 */ 543 void apparmor_bprm_committing_creds(struct linux_binprm *bprm) 544 { 545 struct aa_profile *profile = __aa_current_profile(); 546 struct aa_task_cxt *new_cxt = cred_cxt(bprm->cred); 547 548 /* bail out if unconfined or not changing profile */ 549 if ((new_cxt->profile == profile) || 550 (unconfined(new_cxt->profile))) 551 return; 552 553 current->pdeath_signal = 0; 554 555 /* reset soft limits and set hard limits for the new profile */ 556 __aa_transition_rlimits(profile, new_cxt->profile); 557 } 558 559 /** 560 * apparmor_bprm_commited_cred - do cleanup after new creds committed 561 * @bprm: binprm for the exec (NOT NULL) 562 */ 563 void apparmor_bprm_committed_creds(struct linux_binprm *bprm) 564 { 565 /* TODO: cleanup signals - ipc mediation */ 566 return; 567 } 568 569 /* 570 * Functions for self directed profile change 571 */ 572 573 /** 574 * new_compound_name - create an hname with @n2 appended to @n1 575 * @n1: base of hname (NOT NULL) 576 * @n2: name to append (NOT NULL) 577 * 578 * Returns: new name or NULL on error 579 */ 580 static char *new_compound_name(const char *n1, const char *n2) 581 { 582 char *name = kmalloc(strlen(n1) + strlen(n2) + 3, GFP_KERNEL); 583 if (name) 584 sprintf(name, "%s//%s", n1, n2); 585 return name; 586 } 587 588 /** 589 * aa_change_hat - change hat to/from subprofile 590 * @hats: vector of hat names to try changing into (MAYBE NULL if @count == 0) 591 * @count: number of hat names in @hats 592 * @token: magic value to validate the hat change 593 * @permtest: true if this is just a permission test 594 * 595 * Change to the first profile specified in @hats that exists, and store 596 * the @hat_magic in the current task context. If the count == 0 and the 597 * @token matches that stored in the current task context, return to the 598 * top level profile. 599 * 600 * Returns %0 on success, error otherwise. 601 */ 602 int aa_change_hat(const char *hats[], int count, u64 token, bool permtest) 603 { 604 const struct cred *cred; 605 struct aa_task_cxt *cxt; 606 struct aa_profile *profile, *previous_profile, *hat = NULL; 607 char *name = NULL; 608 int i; 609 struct file_perms perms = {}; 610 const char *target = NULL, *info = NULL; 611 int error = 0; 612 613 /* 614 * Fail explicitly requested domain transitions if no_new_privs. 615 * There is no exception for unconfined as change_hat is not 616 * available. 617 */ 618 if (task_no_new_privs(current)) 619 return -EPERM; 620 621 /* released below */ 622 cred = get_current_cred(); 623 cxt = cred_cxt(cred); 624 profile = aa_cred_profile(cred); 625 previous_profile = cxt->previous; 626 627 if (unconfined(profile)) { 628 info = "unconfined"; 629 error = -EPERM; 630 goto audit; 631 } 632 633 if (count) { 634 /* attempting to change into a new hat or switch to a sibling */ 635 struct aa_profile *root; 636 if (PROFILE_IS_HAT(profile)) 637 root = aa_get_profile_rcu(&profile->parent); 638 else 639 root = aa_get_profile(profile); 640 641 /* find first matching hat */ 642 for (i = 0; i < count && !hat; i++) 643 /* released below */ 644 hat = aa_find_child(root, hats[i]); 645 if (!hat) { 646 if (!COMPLAIN_MODE(root) || permtest) { 647 if (list_empty(&root->base.profiles)) 648 error = -ECHILD; 649 else 650 error = -ENOENT; 651 aa_put_profile(root); 652 goto out; 653 } 654 655 /* 656 * In complain mode and failed to match any hats. 657 * Audit the failure is based off of the first hat 658 * supplied. This is done due how userspace 659 * interacts with change_hat. 660 * 661 * TODO: Add logging of all failed hats 662 */ 663 664 /* freed below */ 665 name = new_compound_name(root->base.hname, hats[0]); 666 aa_put_profile(root); 667 target = name; 668 /* released below */ 669 hat = aa_new_null_profile(profile, 1); 670 if (!hat) { 671 info = "failed null profile create"; 672 error = -ENOMEM; 673 goto audit; 674 } 675 } else { 676 aa_put_profile(root); 677 target = hat->base.hname; 678 if (!PROFILE_IS_HAT(hat)) { 679 info = "target not hat"; 680 error = -EPERM; 681 goto audit; 682 } 683 } 684 685 error = may_change_ptraced_domain(hat); 686 if (error) { 687 info = "ptraced"; 688 error = -EPERM; 689 goto audit; 690 } 691 692 if (!permtest) { 693 error = aa_set_current_hat(hat, token); 694 if (error == -EACCES) 695 /* kill task in case of brute force attacks */ 696 perms.kill = AA_MAY_CHANGEHAT; 697 else if (name && !error) 698 /* reset error for learning of new hats */ 699 error = -ENOENT; 700 } 701 } else if (previous_profile) { 702 /* Return to saved profile. Kill task if restore fails 703 * to avoid brute force attacks 704 */ 705 target = previous_profile->base.hname; 706 error = aa_restore_previous_profile(token); 707 perms.kill = AA_MAY_CHANGEHAT; 708 } else 709 /* ignore restores when there is no saved profile */ 710 goto out; 711 712 audit: 713 if (!permtest) 714 error = aa_audit_file(profile, &perms, GFP_KERNEL, 715 OP_CHANGE_HAT, AA_MAY_CHANGEHAT, NULL, 716 target, GLOBAL_ROOT_UID, info, error); 717 718 out: 719 aa_put_profile(hat); 720 kfree(name); 721 put_cred(cred); 722 723 return error; 724 } 725 726 /** 727 * aa_change_profile - perform a one-way profile transition 728 * @ns_name: name of the profile namespace to change to (MAYBE NULL) 729 * @hname: name of profile to change to (MAYBE NULL) 730 * @onexec: whether this transition is to take place immediately or at exec 731 * @permtest: true if this is just a permission test 732 * 733 * Change to new profile @name. Unlike with hats, there is no way 734 * to change back. If @name isn't specified the current profile name is 735 * used. 736 * If @onexec then the transition is delayed until 737 * the next exec. 738 * 739 * Returns %0 on success, error otherwise. 740 */ 741 int aa_change_profile(const char *ns_name, const char *hname, bool onexec, 742 bool permtest) 743 { 744 const struct cred *cred; 745 struct aa_profile *profile, *target = NULL; 746 struct aa_namespace *ns = NULL; 747 struct file_perms perms = {}; 748 const char *name = NULL, *info = NULL; 749 int op, error = 0; 750 u32 request; 751 752 if (!hname && !ns_name) 753 return -EINVAL; 754 755 if (onexec) { 756 request = AA_MAY_ONEXEC; 757 op = OP_CHANGE_ONEXEC; 758 } else { 759 request = AA_MAY_CHANGE_PROFILE; 760 op = OP_CHANGE_PROFILE; 761 } 762 763 cred = get_current_cred(); 764 profile = aa_cred_profile(cred); 765 766 /* 767 * Fail explicitly requested domain transitions if no_new_privs 768 * and not unconfined. 769 * Domain transitions from unconfined are allowed even when 770 * no_new_privs is set because this aways results in a reduction 771 * of permissions. 772 */ 773 if (task_no_new_privs(current) && !unconfined(profile)) { 774 put_cred(cred); 775 return -EPERM; 776 } 777 778 if (ns_name) { 779 /* released below */ 780 ns = aa_find_namespace(profile->ns, ns_name); 781 if (!ns) { 782 /* we don't create new namespace in complain mode */ 783 name = ns_name; 784 info = "namespace not found"; 785 error = -ENOENT; 786 goto audit; 787 } 788 } else 789 /* released below */ 790 ns = aa_get_namespace(profile->ns); 791 792 /* if the name was not specified, use the name of the current profile */ 793 if (!hname) { 794 if (unconfined(profile)) 795 hname = ns->unconfined->base.hname; 796 else 797 hname = profile->base.hname; 798 } 799 800 perms = change_profile_perms(profile, ns, hname, request, 801 profile->file.start); 802 if (!(perms.allow & request)) { 803 error = -EACCES; 804 goto audit; 805 } 806 807 /* released below */ 808 target = aa_lookup_profile(ns, hname); 809 if (!target) { 810 info = "profile not found"; 811 error = -ENOENT; 812 if (permtest || !COMPLAIN_MODE(profile)) 813 goto audit; 814 /* released below */ 815 target = aa_new_null_profile(profile, 0); 816 if (!target) { 817 info = "failed null profile create"; 818 error = -ENOMEM; 819 goto audit; 820 } 821 } 822 823 /* check if tracing task is allowed to trace target domain */ 824 error = may_change_ptraced_domain(target); 825 if (error) { 826 info = "ptrace prevents transition"; 827 goto audit; 828 } 829 830 if (permtest) 831 goto audit; 832 833 if (onexec) 834 error = aa_set_current_onexec(target); 835 else 836 error = aa_replace_current_profile(target); 837 838 audit: 839 if (!permtest) 840 error = aa_audit_file(profile, &perms, GFP_KERNEL, op, request, 841 name, hname, GLOBAL_ROOT_UID, info, error); 842 843 aa_put_namespace(ns); 844 aa_put_profile(target); 845 put_cred(cred); 846 847 return error; 848 } 849