security/tomoyo/file.c

   1 /*
   2  * security/tomoyo/file.c
   3  *
   4  * Implementation of the Domain-Based Mandatory Access Control.
   5  *
   6  * Copyright (C) 2005-2009  NTT DATA CORPORATION
   7  *
   8  * Version: 2.2.0   2009/04/01
   9  *
  10  */
  11
  12 #include "common.h"
  13 #include "tomoyo.h"
  14 #include "realpath.h"
  15 #define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE])
  16
  17 /* Structure for "allow_read" keyword. */
  18 struct tomoyo_globally_readable_file_entry {
  19         struct list_head list;
  20         const struct tomoyo_path_info *filename;
  21         bool is_deleted;
  22 };
  23
  24 /* Structure for "file_pattern" keyword. */
  25 struct tomoyo_pattern_entry {
  26         struct list_head list;
  27         const struct tomoyo_path_info *pattern;
  28         bool is_deleted;
  29 };
  30
  31 /* Structure for "deny_rewrite" keyword. */
  32 struct tomoyo_no_rewrite_entry {
  33         struct list_head list;
  34         const struct tomoyo_path_info *pattern;
  35         bool is_deleted;
  36 };
  37
  38 /* Keyword array for single path operations. */
  39 static const char *tomoyo_sp_keyword[TOMOYO_MAX_SINGLE_PATH_OPERATION] = {
  40         [TOMOYO_TYPE_READ_WRITE_ACL] = "read/write",
  41         [TOMOYO_TYPE_EXECUTE_ACL]    = "execute",
  42         [TOMOYO_TYPE_READ_ACL]       = "read",
  43         [TOMOYO_TYPE_WRITE_ACL]      = "write",
  44         [TOMOYO_TYPE_CREATE_ACL]     = "create",
  45         [TOMOYO_TYPE_UNLINK_ACL]     = "unlink",
  46         [TOMOYO_TYPE_MKDIR_ACL]      = "mkdir",
  47         [TOMOYO_TYPE_RMDIR_ACL]      = "rmdir",
  48         [TOMOYO_TYPE_MKFIFO_ACL]     = "mkfifo",
  49         [TOMOYO_TYPE_MKSOCK_ACL]     = "mksock",
  50         [TOMOYO_TYPE_MKBLOCK_ACL]    = "mkblock",
  51         [TOMOYO_TYPE_MKCHAR_ACL]     = "mkchar",
  52         [TOMOYO_TYPE_TRUNCATE_ACL]   = "truncate",
  53         [TOMOYO_TYPE_SYMLINK_ACL]    = "symlink",
  54         [TOMOYO_TYPE_REWRITE_ACL]    = "rewrite",
  55 };
  56
  57 /* Keyword array for double path operations. */
  58 static const char *tomoyo_dp_keyword[TOMOYO_MAX_DOUBLE_PATH_OPERATION] = {
  59         [TOMOYO_TYPE_LINK_ACL]    = "link",
  60         [TOMOYO_TYPE_RENAME_ACL]  = "rename",
  61 };
  62
  63 /**
  64  * tomoyo_sp2keyword - Get the name of single path operation.
  65  *
  66  * @operation: Type of operation.
  67  *
  68  * Returns the name of single path operation.
  69  */
  70 const char *tomoyo_sp2keyword(const u8 operation)
  71 {
  72         return (operation < TOMOYO_MAX_SINGLE_PATH_OPERATION)
  73                 ? tomoyo_sp_keyword[operation] : NULL;
  74 }
  75
  76 /**
  77  * tomoyo_dp2keyword - Get the name of double path operation.
  78  *
  79  * @operation: Type of operation.
  80  *
  81  * Returns the name of double path operation.
  82  */
  83 const char *tomoyo_dp2keyword(const u8 operation)
  84 {
  85         return (operation < TOMOYO_MAX_DOUBLE_PATH_OPERATION)
  86                 ? tomoyo_dp_keyword[operation] : NULL;
  87 }
  88
  89 /**
  90  * tomoyo_strendswith - Check whether the token ends with the given token.
  91  *
  92  * @name: The token to check.
  93  * @tail: The token to find.
  94  *
  95  * Returns true if @name ends with @tail, false otherwise.
  96  */
  97 static bool tomoyo_strendswith(const char *name, const char *tail)
  98 {
  99         int len;
 100
 101         if (!name || !tail)
 102                 return false;
 103         len = strlen(name) - strlen(tail);
 104         return len >= 0 && !strcmp(name + len, tail);
 105 }
 106
 107 /**
 108  * tomoyo_get_path - Get realpath.
 109  *
 110  * @path: Pointer to "struct path".
 111  *
 112  * Returns pointer to "struct tomoyo_path_info" on success, NULL otherwise.
 113  */
 114 static struct tomoyo_path_info *tomoyo_get_path(struct path *path)
 115 {
 116         int error;
 117         struct tomoyo_path_info_with_data *buf = tomoyo_alloc(sizeof(*buf));
 118
 119         if (!buf)
 120                 return NULL;
 121         /* Reserve one byte for appending "/". */
 122         error = tomoyo_realpath_from_path2(path, buf->body,
 123                                            sizeof(buf->body) - 2);
 124         if (!error) {
 125                 buf->head.name = buf->body;
 126                 tomoyo_fill_path_info(&buf->head);
 127                 return &buf->head;
 128         }
 129         tomoyo_free(buf);
 130         return NULL;
 131 }
 132
 133 /* Lock for domain->acl_info_list. */
 134 DECLARE_RWSEM(tomoyo_domain_acl_info_list_lock);
 135
 136 static int tomoyo_update_double_path_acl(const u8 type, const char *filename1,
 137                                          const char *filename2,
 138                                          struct tomoyo_domain_info *
 139                                          const domain, const bool is_delete);
 140 static int tomoyo_update_single_path_acl(const u8 type, const char *filename,
 141                                          struct tomoyo_domain_info *
 142                                          const domain, const bool is_delete);
 143
 144 /* The list for "struct tomoyo_globally_readable_file_entry". */
 145 static LIST_HEAD(tomoyo_globally_readable_list);
 146 static DECLARE_RWSEM(tomoyo_globally_readable_list_lock);
 147
 148 /**
 149  * tomoyo_update_globally_readable_entry - Update "struct tomoyo_globally_readable_file_entry" list.
 150  *
 151  * @filename:  Filename unconditionally permitted to open() for reading.
 152  * @is_delete: True if it is a delete request.
 153  *
 154  * Returns 0 on success, negative value otherwise.
 155  */
 156 static int tomoyo_update_globally_readable_entry(const char *filename,
 157                                                  const bool is_delete)
 158 {
 159         struct tomoyo_globally_readable_file_entry *new_entry;
 160         struct tomoyo_globally_readable_file_entry *ptr;
 161         const struct tomoyo_path_info *saved_filename;
 162         int error = -ENOMEM;
 163
 164         if (!tomoyo_is_correct_path(filename, 1, 0, -1, __func__))
 165                 return -EINVAL;
 166         saved_filename = tomoyo_save_name(filename);
 167         if (!saved_filename)
 168                 return -ENOMEM;
 169         /***** EXCLUSIVE SECTION START *****/
 170         down_write(&tomoyo_globally_readable_list_lock);
 171         list_for_each_entry(ptr, &tomoyo_globally_readable_list, list) {
 172                 if (ptr->filename != saved_filename)
 173                         continue;
 174                 ptr->is_deleted = is_delete;
 175                 error = 0;
 176                 goto out;
 177         }
 178         if (is_delete) {
 179                 error = -ENOENT;
 180                 goto out;
 181         }
 182         new_entry = tomoyo_alloc_element(sizeof(*new_entry));
 183         if (!new_entry)
 184                 goto out;
 185         new_entry->filename = saved_filename;
 186         list_add_tail(&new_entry->list, &tomoyo_globally_readable_list);
 187         error = 0;
 188  out:
 189         up_write(&tomoyo_globally_readable_list_lock);
 190         /***** EXCLUSIVE SECTION END *****/
 191         return error;
 192 }
 193
 194 /**
 195  * tomoyo_is_globally_readable_file - Check if the file is unconditionnaly permitted to be open()ed for reading.
 196  *
 197  * @filename: The filename to check.
 198  *
 199  * Returns true if any domain can open @filename for reading, false otherwise.
 200  */
 201 static bool tomoyo_is_globally_readable_file(const struct tomoyo_path_info *
 202                                              filename)
 203 {
 204         struct tomoyo_globally_readable_file_entry *ptr;
 205         bool found = false;
 206         down_read(&tomoyo_globally_readable_list_lock);
 207         list_for_each_entry(ptr, &tomoyo_globally_readable_list, list) {
 208                 if (!ptr->is_deleted &&
 209                     tomoyo_path_matches_pattern(filename, ptr->filename)) {
 210                         found = true;
 211                         break;
 212                 }
 213         }
 214         up_read(&tomoyo_globally_readable_list_lock);
 215         return found;
 216 }
 217
 218 /**
 219  * tomoyo_write_globally_readable_policy - Write "struct tomoyo_globally_readable_file_entry" list.
 220  *
 221  * @data:      String to parse.
 222  * @is_delete: True if it is a delete request.
 223  *
 224  * Returns 0 on success, negative value otherwise.
 225  */
 226 int tomoyo_write_globally_readable_policy(char *data, const bool is_delete)
 227 {
 228         return tomoyo_update_globally_readable_entry(data, is_delete);
 229 }
 230
 231 /**
 232  * tomoyo_read_globally_readable_policy - Read "struct tomoyo_globally_readable_file_entry" list.
 233  *
 234  * @head: Pointer to "struct tomoyo_io_buffer".
 235  *
 236  * Returns true on success, false otherwise.
 237  */
 238 bool tomoyo_read_globally_readable_policy(struct tomoyo_io_buffer *head)
 239 {
 240         struct list_head *pos;
 241         bool done = true;
 242
 243         down_read(&tomoyo_globally_readable_list_lock);
 244         list_for_each_cookie(pos, head->read_var2,
 245                              &tomoyo_globally_readable_list) {
 246                 struct tomoyo_globally_readable_file_entry *ptr;
 247                 ptr = list_entry(pos,
 248                                  struct tomoyo_globally_readable_file_entry,
 249                                  list);
 250                 if (ptr->is_deleted)
 251                         continue;
 252                 if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_ALLOW_READ "%s\n",
 253                                       ptr->filename->name)) {
 254                         done = false;
 255                         break;
 256                 }
 257         }
 258         up_read(&tomoyo_globally_readable_list_lock);
 259         return done;
 260 }
 261
 262 /* The list for "struct tomoyo_pattern_entry". */
 263 static LIST_HEAD(tomoyo_pattern_list);
 264 static DECLARE_RWSEM(tomoyo_pattern_list_lock);
 265
 266 /**
 267  * tomoyo_update_file_pattern_entry - Update "struct tomoyo_pattern_entry" list.
 268  *
 269  * @pattern:   Pathname pattern.
 270  * @is_delete: True if it is a delete request.
 271  *
 272  * Returns 0 on success, negative value otherwise.
 273  */
 274 static int tomoyo_update_file_pattern_entry(const char *pattern,
 275                                             const bool is_delete)
 276 {
 277         struct tomoyo_pattern_entry *new_entry;
 278         struct tomoyo_pattern_entry *ptr;
 279         const struct tomoyo_path_info *saved_pattern;
 280         int error = -ENOMEM;
 281
 282         if (!tomoyo_is_correct_path(pattern, 0, 1, 0, __func__))
 283                 return -EINVAL;
 284         saved_pattern = tomoyo_save_name(pattern);
 285         if (!saved_pattern)
 286                 return -ENOMEM;
 287         /***** EXCLUSIVE SECTION START *****/
 288         down_write(&tomoyo_pattern_list_lock);
 289         list_for_each_entry(ptr, &tomoyo_pattern_list, list) {
 290                 if (saved_pattern != ptr->pattern)
 291                         continue;
 292                 ptr->is_deleted = is_delete;
 293                 error = 0;
 294                 goto out;
 295         }
 296         if (is_delete) {
 297                 error = -ENOENT;
 298                 goto out;
 299         }
 300         new_entry = tomoyo_alloc_element(sizeof(*new_entry));
 301         if (!new_entry)
 302                 goto out;
 303         new_entry->pattern = saved_pattern;
 304         list_add_tail(&new_entry->list, &tomoyo_pattern_list);
 305         error = 0;
 306  out:
 307         up_write(&tomoyo_pattern_list_lock);
 308         /***** EXCLUSIVE SECTION END *****/
 309         return error;
 310 }
 311
 312 /**
 313  * tomoyo_get_file_pattern - Get patterned pathname.
 314  *
 315  * @filename: The filename to find patterned pathname.
 316  *
 317  * Returns pointer to pathname pattern if matched, @filename otherwise.
 318  */
 319 static const struct tomoyo_path_info *
 320 tomoyo_get_file_pattern(const struct tomoyo_path_info *filename)
 321 {
 322         struct tomoyo_pattern_entry *ptr;
 323         const struct tomoyo_path_info *pattern = NULL;
 324
 325         down_read(&tomoyo_pattern_list_lock);
 326         list_for_each_entry(ptr, &tomoyo_pattern_list, list) {
 327                 if (ptr->is_deleted)
 328                         continue;
 329                 if (!tomoyo_path_matches_pattern(filename, ptr->pattern))
 330                         continue;
 331                 pattern = ptr->pattern;
 332                 if (tomoyo_strendswith(pattern->name, "/\\*")) {
 333                         /* Do nothing. Try to find the better match. */
 334                 } else {
 335                         /* This would be the better match. Use this. */
 336                         break;
 337                 }
 338         }
 339         up_read(&tomoyo_pattern_list_lock);
 340         if (pattern)
 341                 filename = pattern;
 342         return filename;
 343 }
 344
 345 /**
 346  * tomoyo_write_pattern_policy - Write "struct tomoyo_pattern_entry" list.
 347  *
 348  * @data:      String to parse.
 349  * @is_delete: True if it is a delete request.
 350  *
 351  * Returns 0 on success, negative value otherwise.
 352  */
 353 int tomoyo_write_pattern_policy(char *data, const bool is_delete)
 354 {
 355         return tomoyo_update_file_pattern_entry(data, is_delete);
 356 }
 357
 358 /**
 359  * tomoyo_read_file_pattern - Read "struct tomoyo_pattern_entry" list.
 360  *
 361  * @head: Pointer to "struct tomoyo_io_buffer".
 362  *
 363  * Returns true on success, false otherwise.
 364  */
 365 bool tomoyo_read_file_pattern(struct tomoyo_io_buffer *head)
 366 {
 367         struct list_head *pos;
 368         bool done = true;
 369
 370         down_read(&tomoyo_pattern_list_lock);
 371         list_for_each_cookie(pos, head->read_var2, &tomoyo_pattern_list) {
 372                 struct tomoyo_pattern_entry *ptr;
 373                 ptr = list_entry(pos, struct tomoyo_pattern_entry, list);
 374                 if (ptr->is_deleted)
 375                         continue;
 376                 if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_FILE_PATTERN "%s\n",
 377                                       ptr->pattern->name)) {
 378                         done = false;
 379                         break;
 380                 }
 381         }
 382         up_read(&tomoyo_pattern_list_lock);
 383         return done;
 384 }
 385
 386 /* The list for "struct tomoyo_no_rewrite_entry". */
 387 static LIST_HEAD(tomoyo_no_rewrite_list);
 388 static DECLARE_RWSEM(tomoyo_no_rewrite_list_lock);
 389
 390 /**
 391  * tomoyo_update_no_rewrite_entry - Update "struct tomoyo_no_rewrite_entry" list.
 392  *
 393  * @pattern:   Pathname pattern that are not rewritable by default.
 394  * @is_delete: True if it is a delete request.
 395  *
 396  * Returns 0 on success, negative value otherwise.
 397  */
 398 static int tomoyo_update_no_rewrite_entry(const char *pattern,
 399                                           const bool is_delete)
 400 {
 401         struct tomoyo_no_rewrite_entry *new_entry, *ptr;
 402         const struct tomoyo_path_info *saved_pattern;
 403         int error = -ENOMEM;
 404
 405         if (!tomoyo_is_correct_path(pattern, 0, 0, 0, __func__))
 406                 return -EINVAL;
 407         saved_pattern = tomoyo_save_name(pattern);
 408         if (!saved_pattern)
 409                 return -ENOMEM;
 410         /***** EXCLUSIVE SECTION START *****/
 411         down_write(&tomoyo_no_rewrite_list_lock);
 412         list_for_each_entry(ptr, &tomoyo_no_rewrite_list, list) {
 413                 if (ptr->pattern != saved_pattern)
 414                         continue;
 415                 ptr->is_deleted = is_delete;
 416                 error = 0;
 417                 goto out;
 418         }
 419         if (is_delete) {
 420                 error = -ENOENT;
 421                 goto out;
 422         }
 423         new_entry = tomoyo_alloc_element(sizeof(*new_entry));
 424         if (!new_entry)
 425                 goto out;
 426         new_entry->pattern = saved_pattern;
 427         list_add_tail(&new_entry->list, &tomoyo_no_rewrite_list);
 428         error = 0;
 429  out:
 430         up_write(&tomoyo_no_rewrite_list_lock);
 431         /***** EXCLUSIVE SECTION END *****/
 432         return error;
 433 }
 434
 435 /**
 436  * tomoyo_is_no_rewrite_file - Check if the given pathname is not permitted to be rewrited.
 437  *
 438  * @filename: Filename to check.
 439  *
 440  * Returns true if @filename is specified by "deny_rewrite" directive,
 441  * false otherwise.
 442  */
 443 static bool tomoyo_is_no_rewrite_file(const struct tomoyo_path_info *filename)
 444 {
 445         struct tomoyo_no_rewrite_entry *ptr;
 446         bool found = false;
 447
 448         down_read(&tomoyo_no_rewrite_list_lock);
 449         list_for_each_entry(ptr, &tomoyo_no_rewrite_list, list) {
 450                 if (ptr->is_deleted)
 451                         continue;
 452                 if (!tomoyo_path_matches_pattern(filename, ptr->pattern))
 453                         continue;
 454                 found = true;
 455                 break;
 456         }
 457         up_read(&tomoyo_no_rewrite_list_lock);
 458         return found;
 459 }
 460
 461 /**
 462  * tomoyo_write_no_rewrite_policy - Write "struct tomoyo_no_rewrite_entry" list.
 463  *
 464  * @data:      String to parse.
 465  * @is_delete: True if it is a delete request.
 466  *
 467  * Returns 0 on success, negative value otherwise.
 468  */
 469 int tomoyo_write_no_rewrite_policy(char *data, const bool is_delete)
 470 {
 471         return tomoyo_update_no_rewrite_entry(data, is_delete);
 472 }
 473
 474 /**
 475  * tomoyo_read_no_rewrite_policy - Read "struct tomoyo_no_rewrite_entry" list.
 476  *
 477  * @head: Pointer to "struct tomoyo_io_buffer".
 478  *
 479  * Returns true on success, false otherwise.
 480  */
 481 bool tomoyo_read_no_rewrite_policy(struct tomoyo_io_buffer *head)
 482 {
 483         struct list_head *pos;
 484         bool done = true;
 485
 486         down_read(&tomoyo_no_rewrite_list_lock);
 487         list_for_each_cookie(pos, head->read_var2, &tomoyo_no_rewrite_list) {
 488                 struct tomoyo_no_rewrite_entry *ptr;
 489                 ptr = list_entry(pos, struct tomoyo_no_rewrite_entry, list);
 490                 if (ptr->is_deleted)
 491                         continue;
 492                 if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_DENY_REWRITE "%s\n",
 493                                       ptr->pattern->name)) {
 494                         done = false;
 495                         break;
 496                 }
 497         }
 498         up_read(&tomoyo_no_rewrite_list_lock);
 499         return done;
 500 }
 501
 502 /**
 503  * tomoyo_update_file_acl - Update file's read/write/execute ACL.
 504  *
 505  * @filename:  Filename.
 506  * @perm:      Permission (between 1 to 7).
 507  * @domain:    Pointer to "struct tomoyo_domain_info".
 508  * @is_delete: True if it is a delete request.
 509  *
 510  * Returns 0 on success, negative value otherwise.
 511  *
 512  * This is legacy support interface for older policy syntax.
 513  * Current policy syntax uses "allow_read/write" instead of "6",
 514  * "allow_read" instead of "4", "allow_write" instead of "2",
 515  * "allow_execute" instead of "1".
 516  */
 517 static int tomoyo_update_file_acl(const char *filename, u8 perm,
 518                                   struct tomoyo_domain_info * const domain,
 519                                   const bool is_delete)
 520 {
 521         if (perm > 7 || !perm) {
 522                 printk(KERN_DEBUG "%s: Invalid permission '%d %s'\n",
 523                        __func__, perm, filename);
 524                 return -EINVAL;
 525         }
 526         if (filename[0] != '@' && tomoyo_strendswith(filename, "/"))
 527                 /*
 528                  * Only 'allow_mkdir' and 'allow_rmdir' are valid for
 529                  * directory permissions.
 530                  */
 531                 return 0;
 532         if (perm & 4)
 533                 tomoyo_update_single_path_acl(TOMOYO_TYPE_READ_ACL, filename,
 534                                               domain, is_delete);
 535         if (perm & 2)
 536                 tomoyo_update_single_path_acl(TOMOYO_TYPE_WRITE_ACL, filename,
 537                                               domain, is_delete);
 538         if (perm & 1)
 539                 tomoyo_update_single_path_acl(TOMOYO_TYPE_EXECUTE_ACL,
 540                                               filename, domain, is_delete);
 541         return 0;
 542 }
 543
 544 /**
 545  * tomoyo_check_single_path_acl2 - Check permission for single path operation.
 546  *
 547  * @domain:          Pointer to "struct tomoyo_domain_info".
 548  * @filename:        Filename to check.
 549  * @perm:            Permission.
 550  * @may_use_pattern: True if patterned ACL is permitted.
 551  *
 552  * Returns 0 on success, -EPERM otherwise.
 553  */
 554 static int tomoyo_check_single_path_acl2(const struct tomoyo_domain_info *
 555                                          domain,
 556                                          const struct tomoyo_path_info *
 557                                          filename,
 558                                          const u16 perm,
 559                                          const bool may_use_pattern)
 560 {
 561         struct tomoyo_acl_info *ptr;
 562         int error = -EPERM;
 563
 564         down_read(&tomoyo_domain_acl_info_list_lock);
 565         list_for_each_entry(ptr, &domain->acl_info_list, list) {
 566                 struct tomoyo_single_path_acl_record *acl;
 567                 if (tomoyo_acl_type2(ptr) != TOMOYO_TYPE_SINGLE_PATH_ACL)
 568                         continue;
 569                 acl = container_of(ptr, struct tomoyo_single_path_acl_record,
 570                                    head);
 571                 if (!(acl->perm & perm))
 572                         continue;
 573                 if (may_use_pattern || !acl->filename->is_patterned) {
 574                         if (!tomoyo_path_matches_pattern(filename,
 575                                                          acl->filename))
 576                                 continue;
 577                 } else {
 578                         continue;
 579                 }
 580                 error = 0;
 581                 break;
 582         }
 583         up_read(&tomoyo_domain_acl_info_list_lock);
 584         return error;
 585 }
 586
 587 /**
 588  * tomoyo_check_file_acl - Check permission for opening files.
 589  *
 590  * @domain:    Pointer to "struct tomoyo_domain_info".
 591  * @filename:  Filename to check.
 592  * @operation: Mode ("read" or "write" or "read/write" or "execute").
 593  *
 594  * Returns 0 on success, -EPERM otherwise.
 595  */
 596 static int tomoyo_check_file_acl(const struct tomoyo_domain_info *domain,
 597                                  const struct tomoyo_path_info *filename,
 598                                  const u8 operation)
 599 {
 600         u16 perm = 0;
 601
 602         if (!tomoyo_check_flags(domain, TOMOYO_MAC_FOR_FILE))
 603                 return 0;
 604         if (operation == 6)
 605                 perm = 1 << TOMOYO_TYPE_READ_WRITE_ACL;
 606         else if (operation == 4)
 607                 perm = 1 << TOMOYO_TYPE_READ_ACL;
 608         else if (operation == 2)
 609                 perm = 1 << TOMOYO_TYPE_WRITE_ACL;
 610         else if (operation == 1)
 611                 perm = 1 << TOMOYO_TYPE_EXECUTE_ACL;
 612         else
 613                 BUG();
 614         return tomoyo_check_single_path_acl2(domain, filename, perm,
 615                                              operation != 1);
 616 }
 617
 618 /**
 619  * tomoyo_check_file_perm2 - Check permission for opening files.
 620  *
 621  * @domain:    Pointer to "struct tomoyo_domain_info".
 622  * @filename:  Filename to check.
 623  * @perm:      Mode ("read" or "write" or "read/write" or "execute").
 624  * @operation: Operation name passed used for verbose mode.
 625  * @mode:      Access control mode.
 626  *
 627  * Returns 0 on success, negative value otherwise.
 628  */
 629 static int tomoyo_check_file_perm2(struct tomoyo_domain_info * const domain,
 630                                    const struct tomoyo_path_info *filename,
 631                                    const u8 perm, const char *operation,
 632                                    const u8 mode)
 633 {
 634         const bool is_enforce = (mode == 3);
 635         const char *msg = "<unknown>";
 636         int error = 0;
 637
 638         if (!filename)
 639                 return 0;
 640         error = tomoyo_check_file_acl(domain, filename, perm);
 641         if (error && perm == 4 &&
 642             (domain->flags & TOMOYO_DOMAIN_FLAGS_IGNORE_GLOBAL_ALLOW_READ) == 0
 643             && tomoyo_is_globally_readable_file(filename))
 644                 error = 0;
 645         if (perm == 6)
 646                 msg = tomoyo_sp2keyword(TOMOYO_TYPE_READ_WRITE_ACL);
 647         else if (perm == 4)
 648                 msg = tomoyo_sp2keyword(TOMOYO_TYPE_READ_ACL);
 649         else if (perm == 2)
 650                 msg = tomoyo_sp2keyword(TOMOYO_TYPE_WRITE_ACL);
 651         else if (perm == 1)
 652                 msg = tomoyo_sp2keyword(TOMOYO_TYPE_EXECUTE_ACL);
 653         else
 654                 BUG();
 655         if (!error)
 656                 return 0;
 657         if (tomoyo_verbose_mode(domain))
 658                 printk(KERN_WARNING "TOMOYO-%s: Access '%s(%s) %s' denied "
 659                        "for %s\n", tomoyo_get_msg(is_enforce), msg, operation,
 660                        filename->name, tomoyo_get_last_name(domain));
 661         if (is_enforce)
 662                 return error;
 663         if (mode == 1 && tomoyo_domain_quota_is_ok(domain)) {
 664                 /* Don't use patterns for execute permission. */
 665                 const struct tomoyo_path_info *patterned_file = (perm != 1) ?
 666                         tomoyo_get_file_pattern(filename) : filename;
 667                 tomoyo_update_file_acl(patterned_file->name, perm,
 668                                        domain, false);
 669         }
 670         return 0;
 671 }
 672
 673 /**
 674  * tomoyo_write_file_policy - Update file related list.
 675  *
 676  * @data:      String to parse.
 677  * @domain:    Pointer to "struct tomoyo_domain_info".
 678  * @is_delete: True if it is a delete request.
 679  *
 680  * Returns 0 on success, negative value otherwise.
 681  */
 682 int tomoyo_write_file_policy(char *data, struct tomoyo_domain_info *domain,
 683                              const bool is_delete)
 684 {
 685         char *filename = strchr(data, ' ');
 686         char *filename2;
 687         unsigned int perm;
 688         u8 type;
 689
 690         if (!filename)
 691                 return -EINVAL;
 692         *filename++ = '\0';
 693         if (sscanf(data, "%u", &perm) == 1)
 694                 return tomoyo_update_file_acl(filename, (u8) perm, domain,
 695                                               is_delete);
 696         if (strncmp(data, "allow_", 6))
 697                 goto out;
 698         data += 6;
 699         for (type = 0; type < TOMOYO_MAX_SINGLE_PATH_OPERATION; type++) {
 700                 if (strcmp(data, tomoyo_sp_keyword[type]))
 701                         continue;
 702                 return tomoyo_update_single_path_acl(type, filename,
 703                                                      domain, is_delete);
 704         }
 705         filename2 = strchr(filename, ' ');
 706         if (!filename2)
 707                 goto out;
 708         *filename2++ = '\0';
 709         for (type = 0; type < TOMOYO_MAX_DOUBLE_PATH_OPERATION; type++) {
 710                 if (strcmp(data, tomoyo_dp_keyword[type]))
 711                         continue;
 712                 return tomoyo_update_double_path_acl(type, filename, filename2,
 713                                                      domain, is_delete);
 714         }
 715  out:
 716         return -EINVAL;
 717 }
 718
 719 /**
 720  * tomoyo_update_single_path_acl - Update "struct tomoyo_single_path_acl_record" list.
 721  *
 722  * @type:      Type of operation.
 723  * @filename:  Filename.
 724  * @domain:    Pointer to "struct tomoyo_domain_info".
 725  * @is_delete: True if it is a delete request.
 726  *
 727  * Returns 0 on success, negative value otherwise.
 728  */
 729 static int tomoyo_update_single_path_acl(const u8 type, const char *filename,
 730                                          struct tomoyo_domain_info *
 731                                          const domain, const bool is_delete)
 732 {
 733         static const u16 rw_mask =
 734                 (1 << TOMOYO_TYPE_READ_ACL) | (1 << TOMOYO_TYPE_WRITE_ACL);
 735         const struct tomoyo_path_info *saved_filename;
 736         struct tomoyo_acl_info *ptr;
 737         struct tomoyo_single_path_acl_record *acl;
 738         int error = -ENOMEM;
 739         const u16 perm = 1 << type;
 740
 741         if (!domain)
 742                 return -EINVAL;
 743         if (!tomoyo_is_correct_path(filename, 0, 0, 0, __func__))
 744                 return -EINVAL;
 745         saved_filename = tomoyo_save_name(filename);
 746         if (!saved_filename)
 747                 return -ENOMEM;
 748         /***** EXCLUSIVE SECTION START *****/
 749         down_write(&tomoyo_domain_acl_info_list_lock);
 750         if (is_delete)
 751                 goto delete;
 752         list_for_each_entry(ptr, &domain->acl_info_list, list) {
 753                 if (tomoyo_acl_type1(ptr) != TOMOYO_TYPE_SINGLE_PATH_ACL)
 754                         continue;
 755                 acl = container_of(ptr, struct tomoyo_single_path_acl_record,
 756                                    head);
 757                 if (acl->filename != saved_filename)
 758                         continue;
 759                 /* Special case. Clear all bits if marked as deleted. */
 760                 if (ptr->type & TOMOYO_ACL_DELETED)
 761                         acl->perm = 0;
 762                 acl->perm |= perm;
 763                 if ((acl->perm & rw_mask) == rw_mask)
 764                         acl->perm |= 1 << TOMOYO_TYPE_READ_WRITE_ACL;
 765                 else if (acl->perm & (1 << TOMOYO_TYPE_READ_WRITE_ACL))
 766                         acl->perm |= rw_mask;
 767                 ptr->type &= ~TOMOYO_ACL_DELETED;
 768                 error = 0;
 769                 goto out;
 770         }
 771         /* Not found. Append it to the tail. */
 772         acl = tomoyo_alloc_acl_element(TOMOYO_TYPE_SINGLE_PATH_ACL);
 773         if (!acl)
 774                 goto out;
 775         acl->perm = perm;
 776         if (perm == (1 << TOMOYO_TYPE_READ_WRITE_ACL))
 777                 acl->perm |= rw_mask;
 778         acl->filename = saved_filename;
 779         list_add_tail(&acl->head.list, &domain->acl_info_list);
 780         error = 0;
 781         goto out;
 782  delete:
 783         error = -ENOENT;
 784         list_for_each_entry(ptr, &domain->acl_info_list, list) {
 785                 if (tomoyo_acl_type2(ptr) != TOMOYO_TYPE_SINGLE_PATH_ACL)
 786                         continue;
 787                 acl = container_of(ptr, struct tomoyo_single_path_acl_record,
 788                                    head);
 789                 if (acl->filename != saved_filename)
 790                         continue;
 791                 acl->perm &= ~perm;
 792                 if ((acl->perm & rw_mask) != rw_mask)
 793                         acl->perm &= ~(1 << TOMOYO_TYPE_READ_WRITE_ACL);
 794                 else if (!(acl->perm & (1 << TOMOYO_TYPE_READ_WRITE_ACL)))
 795                         acl->perm &= ~rw_mask;
 796                 if (!acl->perm)
 797                         ptr->type |= TOMOYO_ACL_DELETED;
 798                 error = 0;
 799                 break;
 800         }
 801  out:
 802         up_write(&tomoyo_domain_acl_info_list_lock);
 803         /***** EXCLUSIVE SECTION END *****/
 804         return error;
 805 }
 806
 807 /**
 808  * tomoyo_update_double_path_acl - Update "struct tomoyo_double_path_acl_record" list.
 809  *
 810  * @type:      Type of operation.
 811  * @filename1: First filename.
 812  * @filename2: Second filename.
 813  * @domain:    Pointer to "struct tomoyo_domain_info".
 814  * @is_delete: True if it is a delete request.
 815  *
 816  * Returns 0 on success, negative value otherwise.
 817  */
 818 static int tomoyo_update_double_path_acl(const u8 type, const char *filename1,
 819                                          const char *filename2,
 820                                          struct tomoyo_domain_info *
 821                                          const domain, const bool is_delete)
 822 {
 823         const struct tomoyo_path_info *saved_filename1;
 824         const struct tomoyo_path_info *saved_filename2;
 825         struct tomoyo_acl_info *ptr;
 826         struct tomoyo_double_path_acl_record *acl;
 827         int error = -ENOMEM;
 828         const u8 perm = 1 << type;
 829
 830         if (!domain)
 831                 return -EINVAL;
 832         if (!tomoyo_is_correct_path(filename1, 0, 0, 0, __func__) ||
 833             !tomoyo_is_correct_path(filename2, 0, 0, 0, __func__))
 834                 return -EINVAL;
 835         saved_filename1 = tomoyo_save_name(filename1);
 836         saved_filename2 = tomoyo_save_name(filename2);
 837         if (!saved_filename1 || !saved_filename2)
 838                 return -ENOMEM;
 839         /***** EXCLUSIVE SECTION START *****/
 840         down_write(&tomoyo_domain_acl_info_list_lock);
 841         if (is_delete)
 842                 goto delete;
 843         list_for_each_entry(ptr, &domain->acl_info_list, list) {
 844                 if (tomoyo_acl_type1(ptr) != TOMOYO_TYPE_DOUBLE_PATH_ACL)
 845                         continue;
 846                 acl = container_of(ptr, struct tomoyo_double_path_acl_record,
 847                                    head);
 848                 if (acl->filename1 != saved_filename1 ||
 849                     acl->filename2 != saved_filename2)
 850                         continue;
 851                 /* Special case. Clear all bits if marked as deleted. */
 852                 if (ptr->type & TOMOYO_ACL_DELETED)
 853                         acl->perm = 0;
 854                 acl->perm |= perm;
 855                 ptr->type &= ~TOMOYO_ACL_DELETED;
 856                 error = 0;
 857                 goto out;
 858         }
 859         /* Not found. Append it to the tail. */
 860         acl = tomoyo_alloc_acl_element(TOMOYO_TYPE_DOUBLE_PATH_ACL);
 861         if (!acl)
 862                 goto out;
 863         acl->perm = perm;
 864         acl->filename1 = saved_filename1;
 865         acl->filename2 = saved_filename2;
 866         list_add_tail(&acl->head.list, &domain->acl_info_list);
 867         error = 0;
 868         goto out;
 869  delete:
 870         error = -ENOENT;
 871         list_for_each_entry(ptr, &domain->acl_info_list, list) {
 872                 if (tomoyo_acl_type2(ptr) != TOMOYO_TYPE_DOUBLE_PATH_ACL)
 873                         continue;
 874                 acl = container_of(ptr, struct tomoyo_double_path_acl_record,
 875                                    head);
 876                 if (acl->filename1 != saved_filename1 ||
 877                     acl->filename2 != saved_filename2)
 878                         continue;
 879                 acl->perm &= ~perm;
 880                 if (!acl->perm)
 881                         ptr->type |= TOMOYO_ACL_DELETED;
 882                 error = 0;
 883                 break;
 884         }
 885  out:
 886         up_write(&tomoyo_domain_acl_info_list_lock);
 887         /***** EXCLUSIVE SECTION END *****/
 888         return error;
 889 }
 890
 891 /**
 892  * tomoyo_check_single_path_acl - Check permission for single path operation.
 893  *
 894  * @domain:   Pointer to "struct tomoyo_domain_info".
 895  * @type:     Type of operation.
 896  * @filename: Filename to check.
 897  *
 898  * Returns 0 on success, negative value otherwise.
 899  */
 900 static int tomoyo_check_single_path_acl(struct tomoyo_domain_info *domain,
 901                                         const u8 type,
 902                                         const struct tomoyo_path_info *filename)
 903 {
 904         if (!tomoyo_check_flags(domain, TOMOYO_MAC_FOR_FILE))
 905                 return 0;
 906         return tomoyo_check_single_path_acl2(domain, filename, 1 << type, 1);
 907 }
 908
 909 /**
 910  * tomoyo_check_double_path_acl - Check permission for double path operation.
 911  *
 912  * @domain:    Pointer to "struct tomoyo_domain_info".
 913  * @type:      Type of operation.
 914  * @filename1: First filename to check.
 915  * @filename2: Second filename to check.
 916  *
 917  * Returns 0 on success, -EPERM otherwise.
 918  */
 919 static int tomoyo_check_double_path_acl(const struct tomoyo_domain_info *domain,
 920                                         const u8 type,
 921                                         const struct tomoyo_path_info *
 922                                         filename1,
 923                                         const struct tomoyo_path_info *
 924                                         filename2)
 925 {
 926         struct tomoyo_acl_info *ptr;
 927         const u8 perm = 1 << type;
 928         int error = -EPERM;
 929
 930         if (!tomoyo_check_flags(domain, TOMOYO_MAC_FOR_FILE))
 931                 return 0;
 932         down_read(&tomoyo_domain_acl_info_list_lock);
 933         list_for_each_entry(ptr, &domain->acl_info_list, list) {
 934                 struct tomoyo_double_path_acl_record *acl;
 935                 if (tomoyo_acl_type2(ptr) != TOMOYO_TYPE_DOUBLE_PATH_ACL)
 936                         continue;
 937                 acl = container_of(ptr, struct tomoyo_double_path_acl_record,
 938                                    head);
 939                 if (!(acl->perm & perm))
 940                         continue;
 941                 if (!tomoyo_path_matches_pattern(filename1, acl->filename1))
 942                         continue;
 943                 if (!tomoyo_path_matches_pattern(filename2, acl->filename2))
 944                         continue;
 945                 error = 0;
 946                 break;
 947         }
 948         up_read(&tomoyo_domain_acl_info_list_lock);
 949         return error;
 950 }
 951
 952 /**
 953  * tomoyo_check_single_path_permission2 - Check permission for single path operation.
 954  *
 955  * @domain:    Pointer to "struct tomoyo_domain_info".
 956  * @operation: Type of operation.
 957  * @filename:  Filename to check.
 958  * @mode:      Access control mode.
 959  *
 960  * Returns 0 on success, negative value otherwise.
 961  */
 962 static int tomoyo_check_single_path_permission2(struct tomoyo_domain_info *
 963                                                 const domain, u8 operation,
 964                                                 const struct tomoyo_path_info *
 965                                                 filename, const u8 mode)
 966 {
 967         const char *msg;
 968         int error;
 969         const bool is_enforce = (mode == 3);
 970
 971         if (!mode)
 972                 return 0;
 973  next:
 974         error = tomoyo_check_single_path_acl(domain, operation, filename);
 975         msg = tomoyo_sp2keyword(operation);
 976         if (!error)
 977                 goto ok;
 978         if (tomoyo_verbose_mode(domain))
 979                 printk(KERN_WARNING "TOMOYO-%s: Access '%s %s' denied for %s\n",
 980                        tomoyo_get_msg(is_enforce), msg, filename->name,
 981                        tomoyo_get_last_name(domain));
 982         if (mode == 1 && tomoyo_domain_quota_is_ok(domain)) {
 983                 const char *name = tomoyo_get_file_pattern(filename)->name;
 984                 tomoyo_update_single_path_acl(operation, name, domain, false);
 985         }
 986         if (!is_enforce)
 987                 error = 0;
 988  ok:
 989         /*
 990          * Since "allow_truncate" doesn't imply "allow_rewrite" permission,
 991          * we need to check "allow_rewrite" permission if the filename is
 992          * specified by "deny_rewrite" keyword.
 993          */
 994         if (!error && operation == TOMOYO_TYPE_TRUNCATE_ACL &&
 995             tomoyo_is_no_rewrite_file(filename)) {
 996                 operation = TOMOYO_TYPE_REWRITE_ACL;
 997                 goto next;
 998         }
 999         return error;
1000 }
1001
1002 /**
1003  * tomoyo_check_file_perm - Check permission for sysctl()'s "read" and "write".
1004  *
1005  * @domain:    Pointer to "struct tomoyo_domain_info".
1006  * @filename:  Filename to check.
1007  * @perm:      Mode ("read" or "write" or "read/write").
1008  * Returns 0 on success, negative value otherwise.
1009  */
1010 int tomoyo_check_file_perm(struct tomoyo_domain_info *domain,
1011                            const char *filename, const u8 perm)
1012 {
1013         struct tomoyo_path_info name;
1014         const u8 mode = tomoyo_check_flags(domain, TOMOYO_MAC_FOR_FILE);
1015
1016         if (!mode)
1017                 return 0;
1018         name.name = filename;
1019         tomoyo_fill_path_info(&name);
1020         return tomoyo_check_file_perm2(domain, &name, perm, "sysctl", mode);
1021 }
1022
1023 /**
1024  * tomoyo_check_exec_perm - Check permission for "execute".
1025  *
1026  * @domain:   Pointer to "struct tomoyo_domain_info".
1027  * @filename: Check permission for "execute".
1028  * @tmp:      Buffer for temporary use.
1029  *
1030  * Returns 0 on success, negativevalue otherwise.
1031  */
1032 int tomoyo_check_exec_perm(struct tomoyo_domain_info *domain,
1033                            const struct tomoyo_path_info *filename,
1034                            struct tomoyo_page_buffer *tmp)
1035 {
1036         const u8 mode = tomoyo_check_flags(domain, TOMOYO_MAC_FOR_FILE);
1037
1038         if (!mode)
1039                 return 0;
1040         return tomoyo_check_file_perm2(domain, filename, 1, "do_execve", mode);
1041 }
1042
1043 /**
1044  * tomoyo_check_open_permission - Check permission for "read" and "write".
1045  *
1046  * @domain: Pointer to "struct tomoyo_domain_info".
1047  * @path:   Pointer to "struct path".
1048  * @flag:   Flags for open().
1049  *
1050  * Returns 0 on success, negative value otherwise.
1051  */
1052 int tomoyo_check_open_permission(struct tomoyo_domain_info *domain,
1053                                  struct path *path, const int flag)
1054 {
1055         const u8 acc_mode = ACC_MODE(flag);
1056         int error = -ENOMEM;
1057         struct tomoyo_path_info *buf;
1058         const u8 mode = tomoyo_check_flags(domain, TOMOYO_MAC_FOR_FILE);
1059         const bool is_enforce = (mode == 3);
1060
1061         if (!mode || !path->mnt)
1062                 return 0;
1063         if (acc_mode == 0)
1064                 return 0;
1065         if (path->dentry->d_inode && S_ISDIR(path->dentry->d_inode->i_mode))
1066                 /*
1067                  * I don't check directories here because mkdir() and rmdir()
1068                  * don't call me.
1069                  */
1070                 return 0;
1071         buf = tomoyo_get_path(path);
1072         if (!buf)
1073                 goto out;
1074         error = 0;
1075         /*
1076          * If the filename is specified by "deny_rewrite" keyword,
1077          * we need to check "allow_rewrite" permission when the filename is not
1078          * opened for append mode or the filename is truncated at open time.
1079          */
1080         if ((acc_mode & MAY_WRITE) &&
1081             ((flag & O_TRUNC) || !(flag & O_APPEND)) &&
1082             (tomoyo_is_no_rewrite_file(buf))) {
1083                 error = tomoyo_check_single_path_permission2(domain,
1084                                                      TOMOYO_TYPE_REWRITE_ACL,
1085                                                              buf, mode);
1086         }
1087         if (!error)
1088                 error = tomoyo_check_file_perm2(domain, buf, acc_mode, "open",
1089                                                 mode);
1090         if (!error && (flag & O_TRUNC))
1091                 error = tomoyo_check_single_path_permission2(domain,
1092                                                      TOMOYO_TYPE_TRUNCATE_ACL,
1093                                                              buf, mode);
1094  out:
1095         tomoyo_free(buf);
1096         if (!is_enforce)
1097                 error = 0;
1098         return error;
1099 }
1100
1101 /**
1102  * tomoyo_check_1path_perm - Check permission for "create", "unlink", "mkdir", "rmdir", "mkfifo", "mksock", "mkblock", "mkchar", "truncate" and "symlink".
1103  *
1104  * @domain:    Pointer to "struct tomoyo_domain_info".
1105  * @operation: Type of operation.
1106  * @path:      Pointer to "struct path".
1107  *
1108  * Returns 0 on success, negative value otherwise.
1109  */
1110 int tomoyo_check_1path_perm(struct tomoyo_domain_info *domain,
1111                             const u8 operation, struct path *path)
1112 {
1113         int error = -ENOMEM;
1114         struct tomoyo_path_info *buf;
1115         const u8 mode = tomoyo_check_flags(domain, TOMOYO_MAC_FOR_FILE);
1116         const bool is_enforce = (mode == 3);
1117
1118         if (!mode || !path->mnt)
1119                 return 0;
1120         buf = tomoyo_get_path(path);
1121         if (!buf)
1122                 goto out;
1123         switch (operation) {
1124         case TOMOYO_TYPE_MKDIR_ACL:
1125         case TOMOYO_TYPE_RMDIR_ACL:
1126                 if (!buf->is_dir) {
1127                         /*
1128                          * tomoyo_get_path() reserves space for appending "/."
1129                          */
1130                         strcat((char *) buf->name, "/");
1131                         tomoyo_fill_path_info(buf);
1132                 }
1133         }
1134         error = tomoyo_check_single_path_permission2(domain, operation, buf,
1135                                                      mode);
1136  out:
1137         tomoyo_free(buf);
1138         if (!is_enforce)
1139                 error = 0;
1140         return error;
1141 }
1142
1143 /**
1144  * tomoyo_check_rewrite_permission - Check permission for "rewrite".
1145  *
1146  * @domain: Pointer to "struct tomoyo_domain_info".
1147  * @filp: Pointer to "struct file".
1148  *
1149  * Returns 0 on success, negative value otherwise.
1150  */
1151 int tomoyo_check_rewrite_permission(struct tomoyo_domain_info *domain,
1152                                     struct file *filp)
1153 {
1154         int error = -ENOMEM;
1155         const u8 mode = tomoyo_check_flags(domain, TOMOYO_MAC_FOR_FILE);
1156         const bool is_enforce = (mode == 3);
1157         struct tomoyo_path_info *buf;
1158
1159         if (!mode || !filp->f_path.mnt)
1160                 return 0;
1161         buf = tomoyo_get_path(&filp->f_path);
1162         if (!buf)
1163                 goto out;
1164         if (!tomoyo_is_no_rewrite_file(buf)) {
1165                 error = 0;
1166                 goto out;
1167         }
1168         error = tomoyo_check_single_path_permission2(domain,
1169                                                      TOMOYO_TYPE_REWRITE_ACL,
1170                                                      buf, mode);
1171  out:
1172         tomoyo_free(buf);
1173         if (!is_enforce)
1174                 error = 0;
1175         return error;
1176 }
1177
1178 /**
1179  * tomoyo_check_2path_perm - Check permission for "rename" and "link".
1180  *
1181  * @domain:    Pointer to "struct tomoyo_domain_info".
1182  * @operation: Type of operation.
1183  * @path1:      Pointer to "struct path".
1184  * @path2:      Pointer to "struct path".
1185  *
1186  * Returns 0 on success, negative value otherwise.
1187  */
1188 int tomoyo_check_2path_perm(struct tomoyo_domain_info * const domain,
1189                             const u8 operation, struct path *path1,
1190                             struct path *path2)
1191 {
1192         int error = -ENOMEM;
1193         struct tomoyo_path_info *buf1, *buf2;
1194         const u8 mode = tomoyo_check_flags(domain, TOMOYO_MAC_FOR_FILE);
1195         const bool is_enforce = (mode == 3);
1196         const char *msg;
1197
1198         if (!mode || !path1->mnt || !path2->mnt)
1199                 return 0;
1200         buf1 = tomoyo_get_path(path1);
1201         buf2 = tomoyo_get_path(path2);
1202         if (!buf1 || !buf2)
1203                 goto out;
1204         {
1205                 struct dentry *dentry = path1->dentry;
1206                 if (dentry->d_inode && S_ISDIR(dentry->d_inode->i_mode)) {
1207                         /*
1208                          * tomoyo_get_path() reserves space for appending "/."
1209                          */
1210                         if (!buf1->is_dir) {
1211                                 strcat((char *) buf1->name, "/");
1212                                 tomoyo_fill_path_info(buf1);
1213                         }
1214                         if (!buf2->is_dir) {
1215                                 strcat((char *) buf2->name, "/");
1216                                 tomoyo_fill_path_info(buf2);
1217                         }
1218                 }
1219         }
1220         error = tomoyo_check_double_path_acl(domain, operation, buf1, buf2);
1221         msg = tomoyo_dp2keyword(operation);
1222         if (!error)
1223                 goto out;
1224         if (tomoyo_verbose_mode(domain))
1225                 printk(KERN_WARNING "TOMOYO-%s: Access '%s %s %s' "
1226                        "denied for %s\n", tomoyo_get_msg(is_enforce),
1227                        msg, buf1->name, buf2->name,
1228                        tomoyo_get_last_name(domain));
1229         if (mode == 1 && tomoyo_domain_quota_is_ok(domain)) {
1230                 const char *name1 = tomoyo_get_file_pattern(buf1)->name;
1231                 const char *name2 = tomoyo_get_file_pattern(buf2)->name;
1232                 tomoyo_update_double_path_acl(operation, name1, name2, domain,
1233                                               false);
1234         }
1235  out:
1236         tomoyo_free(buf1);
1237         tomoyo_free(buf2);
1238         if (!is_enforce)
1239                 error = 0;
1240         return error;
1241 }