fsck.c

   1 #include "cache.h"
   2 #include "object-store.h"
   3 #include "repository.h"
   4 #include "object.h"
   5 #include "blob.h"
   6 #include "tree.h"
   7 #include "tree-walk.h"
   8 #include "commit.h"
   9 #include "tag.h"
  10 #include "fsck.h"
  11 #include "refs.h"
  12 #include "url.h"
  13 #include "utf8.h"
  14 #include "decorate.h"
  15 #include "oidset.h"
  16 #include "packfile.h"
  17 #include "submodule-config.h"
  18 #include "config.h"
  19 #include "credential.h"
  20 #include "help.h"
  21
  22 static struct oidset gitmodules_found = OIDSET_INIT;
  23 static struct oidset gitmodules_done = OIDSET_INIT;
  24
  25 #define FSCK_FATAL -1
  26 #define FSCK_INFO -2
  27
  28 #define FOREACH_MSG_ID(FUNC) \
  29         /* fatal errors */ \
  30         FUNC(NUL_IN_HEADER, FATAL) \
  31         FUNC(UNTERMINATED_HEADER, FATAL) \
  32         /* errors */ \
  33         FUNC(BAD_DATE, ERROR) \
  34         FUNC(BAD_DATE_OVERFLOW, ERROR) \
  35         FUNC(BAD_EMAIL, ERROR) \
  36         FUNC(BAD_NAME, ERROR) \
  37         FUNC(BAD_OBJECT_SHA1, ERROR) \
  38         FUNC(BAD_PARENT_SHA1, ERROR) \
  39         FUNC(BAD_TAG_OBJECT, ERROR) \
  40         FUNC(BAD_TIMEZONE, ERROR) \
  41         FUNC(BAD_TREE, ERROR) \
  42         FUNC(BAD_TREE_SHA1, ERROR) \
  43         FUNC(BAD_TYPE, ERROR) \
  44         FUNC(DUPLICATE_ENTRIES, ERROR) \
  45         FUNC(MISSING_AUTHOR, ERROR) \
  46         FUNC(MISSING_COMMITTER, ERROR) \
  47         FUNC(MISSING_EMAIL, ERROR) \
  48         FUNC(MISSING_NAME_BEFORE_EMAIL, ERROR) \
  49         FUNC(MISSING_OBJECT, ERROR) \
  50         FUNC(MISSING_SPACE_BEFORE_DATE, ERROR) \
  51         FUNC(MISSING_SPACE_BEFORE_EMAIL, ERROR) \
  52         FUNC(MISSING_TAG, ERROR) \
  53         FUNC(MISSING_TAG_ENTRY, ERROR) \
  54         FUNC(MISSING_TREE, ERROR) \
  55         FUNC(MISSING_TREE_OBJECT, ERROR) \
  56         FUNC(MISSING_TYPE, ERROR) \
  57         FUNC(MISSING_TYPE_ENTRY, ERROR) \
  58         FUNC(MULTIPLE_AUTHORS, ERROR) \
  59         FUNC(TREE_NOT_SORTED, ERROR) \
  60         FUNC(UNKNOWN_TYPE, ERROR) \
  61         FUNC(ZERO_PADDED_DATE, ERROR) \
  62         FUNC(GITMODULES_MISSING, ERROR) \
  63         FUNC(GITMODULES_BLOB, ERROR) \
  64         FUNC(GITMODULES_LARGE, ERROR) \
  65         FUNC(GITMODULES_NAME, ERROR) \
  66         FUNC(GITMODULES_SYMLINK, ERROR) \
  67         FUNC(GITMODULES_URL, ERROR) \
  68         FUNC(GITMODULES_PATH, ERROR) \
  69         FUNC(GITMODULES_UPDATE, ERROR) \
  70         /* warnings */ \
  71         FUNC(BAD_FILEMODE, WARN) \
  72         FUNC(EMPTY_NAME, WARN) \
  73         FUNC(FULL_PATHNAME, WARN) \
  74         FUNC(HAS_DOT, WARN) \
  75         FUNC(HAS_DOTDOT, WARN) \
  76         FUNC(HAS_DOTGIT, WARN) \
  77         FUNC(NULL_SHA1, WARN) \
  78         FUNC(ZERO_PADDED_FILEMODE, WARN) \
  79         FUNC(NUL_IN_COMMIT, WARN) \
  80         /* infos (reported as warnings, but ignored by default) */ \
  81         FUNC(GITMODULES_PARSE, INFO) \
  82         FUNC(BAD_TAG_NAME, INFO) \
  83         FUNC(MISSING_TAGGER_ENTRY, INFO) \
  84         /* ignored (elevated when requested) */ \
  85         FUNC(EXTRA_HEADER_ENTRY, IGNORE)
  86
  87 #define MSG_ID(id, msg_type) FSCK_MSG_##id,
  88 enum fsck_msg_id {
  89         FOREACH_MSG_ID(MSG_ID)
  90         FSCK_MSG_MAX
  91 };
  92 #undef MSG_ID
  93
  94 #define STR(x) #x
  95 #define MSG_ID(id, msg_type) { STR(id), NULL, NULL, FSCK_##msg_type },
  96 static struct {
  97         const char *id_string;
  98         const char *downcased;
  99         const char *camelcased;
 100         int msg_type;
 101 } msg_id_info[FSCK_MSG_MAX + 1] = {
 102         FOREACH_MSG_ID(MSG_ID)
 103         { NULL, NULL, NULL, -1 }
 104 };
 105 #undef MSG_ID
 106
 107 static void prepare_msg_ids(void)
 108 {
 109         int i;
 110
 111         if (msg_id_info[0].downcased)
 112                 return;
 113
 114         /* convert id_string to lower case, without underscores. */
 115         for (i = 0; i < FSCK_MSG_MAX; i++) {
 116                 const char *p = msg_id_info[i].id_string;
 117                 int len = strlen(p);
 118                 char *q = xmalloc(len);
 119
 120                 msg_id_info[i].downcased = q;
 121                 while (*p)
 122                         if (*p == '_')
 123                                 p++;
 124                         else
 125                                 *(q)++ = tolower(*(p)++);
 126                 *q = '\0';
 127
 128                 p = msg_id_info[i].id_string;
 129                 q = xmalloc(len);
 130                 msg_id_info[i].camelcased = q;
 131                 while (*p) {
 132                         if (*p == '_') {
 133                                 p++;
 134                                 if (*p)
 135                                         *q++ = *p++;
 136                         } else {
 137                                 *q++ = tolower(*p++);
 138                         }
 139                 }
 140                 *q = '\0';
 141         }
 142 }
 143
 144 static int parse_msg_id(const char *text)
 145 {
 146         int i;
 147
 148         prepare_msg_ids();
 149
 150         for (i = 0; i < FSCK_MSG_MAX; i++)
 151                 if (!strcmp(text, msg_id_info[i].downcased))
 152                         return i;
 153
 154         return -1;
 155 }
 156
 157 void list_config_fsck_msg_ids(struct string_list *list, const char *prefix)
 158 {
 159         int i;
 160
 161         prepare_msg_ids();
 162
 163         for (i = 0; i < FSCK_MSG_MAX; i++)
 164                 list_config_item(list, prefix, msg_id_info[i].camelcased);
 165 }
 166
 167 static int fsck_msg_type(enum fsck_msg_id msg_id,
 168         struct fsck_options *options)
 169 {
 170         int msg_type;
 171
 172         assert(msg_id >= 0 && msg_id < FSCK_MSG_MAX);
 173
 174         if (options->msg_type)
 175                 msg_type = options->msg_type[msg_id];
 176         else {
 177                 msg_type = msg_id_info[msg_id].msg_type;
 178                 if (options->strict && msg_type == FSCK_WARN)
 179                         msg_type = FSCK_ERROR;
 180         }
 181
 182         return msg_type;
 183 }
 184
 185 static int parse_msg_type(const char *str)
 186 {
 187         if (!strcmp(str, "error"))
 188                 return FSCK_ERROR;
 189         else if (!strcmp(str, "warn"))
 190                 return FSCK_WARN;
 191         else if (!strcmp(str, "ignore"))
 192                 return FSCK_IGNORE;
 193         else
 194                 die("Unknown fsck message type: '%s'", str);
 195 }
 196
 197 int is_valid_msg_type(const char *msg_id, const char *msg_type)
 198 {
 199         if (parse_msg_id(msg_id) < 0)
 200                 return 0;
 201         parse_msg_type(msg_type);
 202         return 1;
 203 }
 204
 205 void fsck_set_msg_type(struct fsck_options *options,
 206                 const char *msg_id, const char *msg_type)
 207 {
 208         int id = parse_msg_id(msg_id), type;
 209
 210         if (id < 0)
 211                 die("Unhandled message id: %s", msg_id);
 212         type = parse_msg_type(msg_type);
 213
 214         if (type != FSCK_ERROR && msg_id_info[id].msg_type == FSCK_FATAL)
 215                 die("Cannot demote %s to %s", msg_id, msg_type);
 216
 217         if (!options->msg_type) {
 218                 int i;
 219                 int *msg_type;
 220                 ALLOC_ARRAY(msg_type, FSCK_MSG_MAX);
 221                 for (i = 0; i < FSCK_MSG_MAX; i++)
 222                         msg_type[i] = fsck_msg_type(i, options);
 223                 options->msg_type = msg_type;
 224         }
 225
 226         options->msg_type[id] = type;
 227 }
 228
 229 void fsck_set_msg_types(struct fsck_options *options, const char *values)
 230 {
 231         char *buf = xstrdup(values), *to_free = buf;
 232         int done = 0;
 233
 234         while (!done) {
 235                 int len = strcspn(buf, " ,|"), equal;
 236
 237                 done = !buf[len];
 238                 if (!len) {
 239                         buf++;
 240                         continue;
 241                 }
 242                 buf[len] = '\0';
 243
 244                 for (equal = 0;
 245                      equal < len && buf[equal] != '=' && buf[equal] != ':';
 246                      equal++)
 247                         buf[equal] = tolower(buf[equal]);
 248                 buf[equal] = '\0';
 249
 250                 if (!strcmp(buf, "skiplist")) {
 251                         if (equal == len)
 252                                 die("skiplist requires a path");
 253                         oidset_parse_file(&options->skiplist, buf + equal + 1);
 254                         buf += len + 1;
 255                         continue;
 256                 }
 257
 258                 if (equal == len)
 259                         die("Missing '=': '%s'", buf);
 260
 261                 fsck_set_msg_type(options, buf, buf + equal + 1);
 262                 buf += len + 1;
 263         }
 264         free(to_free);
 265 }
 266
 267 static void append_msg_id(struct strbuf *sb, const char *msg_id)
 268 {
 269         for (;;) {
 270                 char c = *(msg_id)++;
 271
 272                 if (!c)
 273                         break;
 274                 if (c != '_')
 275                         strbuf_addch(sb, tolower(c));
 276                 else {
 277                         assert(*msg_id);
 278                         strbuf_addch(sb, *(msg_id)++);
 279                 }
 280         }
 281
 282         strbuf_addstr(sb, ": ");
 283 }
 284
 285 static int object_on_skiplist(struct fsck_options *opts,
 286                               const struct object_id *oid)
 287 {
 288         return opts && oid && oidset_contains(&opts->skiplist, oid);
 289 }
 290
 291 __attribute__((format (printf, 5, 6)))
 292 static int report(struct fsck_options *options,
 293                   const struct object_id *oid, enum object_type object_type,
 294                   enum fsck_msg_id id, const char *fmt, ...)
 295 {
 296         va_list ap;
 297         struct strbuf sb = STRBUF_INIT;
 298         int msg_type = fsck_msg_type(id, options), result;
 299
 300         if (msg_type == FSCK_IGNORE)
 301                 return 0;
 302
 303         if (object_on_skiplist(options, oid))
 304                 return 0;
 305
 306         if (msg_type == FSCK_FATAL)
 307                 msg_type = FSCK_ERROR;
 308         else if (msg_type == FSCK_INFO)
 309                 msg_type = FSCK_WARN;
 310
 311         append_msg_id(&sb, msg_id_info[id].id_string);
 312
 313         va_start(ap, fmt);
 314         strbuf_vaddf(&sb, fmt, ap);
 315         result = options->error_func(options, oid, object_type,
 316                                      msg_type, sb.buf);
 317         strbuf_release(&sb);
 318         va_end(ap);
 319
 320         return result;
 321 }
 322
 323 void fsck_enable_object_names(struct fsck_options *options)
 324 {
 325         if (!options->object_names)
 326                 options->object_names = kh_init_oid_map();
 327 }
 328
 329 const char *fsck_get_object_name(struct fsck_options *options,
 330                                  const struct object_id *oid)
 331 {
 332         khiter_t pos;
 333         if (!options->object_names)
 334                 return NULL;
 335         pos = kh_get_oid_map(options->object_names, *oid);
 336         if (pos >= kh_end(options->object_names))
 337                 return NULL;
 338         return kh_value(options->object_names, pos);
 339 }
 340
 341 void fsck_put_object_name(struct fsck_options *options,
 342                           const struct object_id *oid,
 343                           const char *fmt, ...)
 344 {
 345         va_list ap;
 346         struct strbuf buf = STRBUF_INIT;
 347         khiter_t pos;
 348         int hashret;
 349
 350         if (!options->object_names)
 351                 return;
 352
 353         pos = kh_put_oid_map(options->object_names, *oid, &hashret);
 354         if (!hashret)
 355                 return;
 356         va_start(ap, fmt);
 357         strbuf_vaddf(&buf, fmt, ap);
 358         kh_value(options->object_names, pos) = strbuf_detach(&buf, NULL);
 359         va_end(ap);
 360 }
 361
 362 const char *fsck_describe_object(struct fsck_options *options,
 363                                  const struct object_id *oid)
 364 {
 365         static struct strbuf bufs[] = {
 366                 STRBUF_INIT, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT
 367         };
 368         static int b = 0;
 369         struct strbuf *buf;
 370         const char *name = fsck_get_object_name(options, oid);
 371
 372         buf = bufs + b;
 373         b = (b + 1) % ARRAY_SIZE(bufs);
 374         strbuf_reset(buf);
 375         strbuf_addstr(buf, oid_to_hex(oid));
 376         if (name)
 377                 strbuf_addf(buf, " (%s)", name);
 378
 379         return buf->buf;
 380 }
 381
 382 static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *options)
 383 {
 384         struct tree_desc desc;
 385         struct name_entry entry;
 386         int res = 0;
 387         const char *name;
 388
 389         if (parse_tree(tree))
 390                 return -1;
 391
 392         name = fsck_get_object_name(options, &tree->object.oid);
 393         if (init_tree_desc_gently(&desc, tree->buffer, tree->size))
 394                 return -1;
 395         while (tree_entry_gently(&desc, &entry)) {
 396                 struct object *obj;
 397                 int result;
 398
 399                 if (S_ISGITLINK(entry.mode))
 400                         continue;
 401
 402                 if (S_ISDIR(entry.mode)) {
 403                         obj = (struct object *)lookup_tree(the_repository, &entry.oid);
 404                         if (name && obj)
 405                                 fsck_put_object_name(options, &entry.oid, "%s%s/",
 406                                                      name, entry.path);
 407                         result = options->walk(obj, OBJ_TREE, data, options);
 408                 }
 409                 else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode)) {
 410                         obj = (struct object *)lookup_blob(the_repository, &entry.oid);
 411                         if (name && obj)
 412                                 fsck_put_object_name(options, &entry.oid, "%s%s",
 413                                                      name, entry.path);
 414                         result = options->walk(obj, OBJ_BLOB, data, options);
 415                 }
 416                 else {
 417                         result = error("in tree %s: entry %s has bad mode %.6o",
 418                                        fsck_describe_object(options, &tree->object.oid),
 419                                        entry.path, entry.mode);
 420                 }
 421                 if (result < 0)
 422                         return result;
 423                 if (!res)
 424                         res = result;
 425         }
 426         return res;
 427 }
 428
 429 static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_options *options)
 430 {
 431         int counter = 0, generation = 0, name_prefix_len = 0;
 432         struct commit_list *parents;
 433         int res;
 434         int result;
 435         const char *name;
 436
 437         if (parse_commit(commit))
 438                 return -1;
 439
 440         name = fsck_get_object_name(options, &commit->object.oid);
 441         if (name)
 442                 fsck_put_object_name(options, get_commit_tree_oid(commit),
 443                                      "%s:", name);
 444
 445         result = options->walk((struct object *)get_commit_tree(commit),
 446                                OBJ_TREE, data, options);
 447         if (result < 0)
 448                 return result;
 449         res = result;
 450
 451         parents = commit->parents;
 452         if (name && parents) {
 453                 int len = strlen(name), power;
 454
 455                 if (len && name[len - 1] == '^') {
 456                         generation = 1;
 457                         name_prefix_len = len - 1;
 458                 }
 459                 else { /* parse ~<generation> suffix */
 460                         for (generation = 0, power = 1;
 461                              len && isdigit(name[len - 1]);
 462                              power *= 10)
 463                                 generation += power * (name[--len] - '0');
 464                         if (power > 1 && len && name[len - 1] == '~')
 465                                 name_prefix_len = len - 1;
 466                         else {
 467                                 /* Maybe a non-first parent, e.g. HEAD^2 */
 468                                 generation = 0;
 469                                 name_prefix_len = len;
 470                         }
 471                 }
 472         }
 473
 474         while (parents) {
 475                 if (name) {
 476                         struct object_id *oid = &parents->item->object.oid;
 477
 478                         if (counter++)
 479                                 fsck_put_object_name(options, oid, "%s^%d",
 480                                                      name, counter);
 481                         else if (generation > 0)
 482                                 fsck_put_object_name(options, oid, "%.*s~%d",
 483                                                      name_prefix_len, name,
 484                                                      generation + 1);
 485                         else
 486                                 fsck_put_object_name(options, oid, "%s^", name);
 487                 }
 488                 result = options->walk((struct object *)parents->item, OBJ_COMMIT, data, options);
 489                 if (result < 0)
 490                         return result;
 491                 if (!res)
 492                         res = result;
 493                 parents = parents->next;
 494         }
 495         return res;
 496 }
 497
 498 static int fsck_walk_tag(struct tag *tag, void *data, struct fsck_options *options)
 499 {
 500         const char *name = fsck_get_object_name(options, &tag->object.oid);
 501
 502         if (parse_tag(tag))
 503                 return -1;
 504         if (name)
 505                 fsck_put_object_name(options, &tag->tagged->oid, "%s", name);
 506         return options->walk(tag->tagged, OBJ_ANY, data, options);
 507 }
 508
 509 int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
 510 {
 511         if (!obj)
 512                 return -1;
 513
 514         if (obj->type == OBJ_NONE)
 515                 parse_object(the_repository, &obj->oid);
 516
 517         switch (obj->type) {
 518         case OBJ_BLOB:
 519                 return 0;
 520         case OBJ_TREE:
 521                 return fsck_walk_tree((struct tree *)obj, data, options);
 522         case OBJ_COMMIT:
 523                 return fsck_walk_commit((struct commit *)obj, data, options);
 524         case OBJ_TAG:
 525                 return fsck_walk_tag((struct tag *)obj, data, options);
 526         default:
 527                 error("Unknown object type for %s",
 528                       fsck_describe_object(options, &obj->oid));
 529                 return -1;
 530         }
 531 }
 532
 533 struct name_stack {
 534         const char **names;
 535         size_t nr, alloc;
 536 };
 537
 538 static void name_stack_push(struct name_stack *stack, const char *name)
 539 {
 540         ALLOC_GROW(stack->names, stack->nr + 1, stack->alloc);
 541         stack->names[stack->nr++] = name;
 542 }
 543
 544 static const char *name_stack_pop(struct name_stack *stack)
 545 {
 546         return stack->nr ? stack->names[--stack->nr] : NULL;
 547 }
 548
 549 static void name_stack_clear(struct name_stack *stack)
 550 {
 551         FREE_AND_NULL(stack->names);
 552         stack->nr = stack->alloc = 0;
 553 }
 554
 555 /*
 556  * The entries in a tree are ordered in the _path_ order,
 557  * which means that a directory entry is ordered by adding
 558  * a slash to the end of it.
 559  *
 560  * So a directory called "a" is ordered _after_ a file
 561  * called "a.c", because "a/" sorts after "a.c".
 562  */
 563 #define TREE_UNORDERED (-1)
 564 #define TREE_HAS_DUPS  (-2)
 565
 566 static int is_less_than_slash(unsigned char c)
 567 {
 568         return '\0' < c && c < '/';
 569 }
 570
 571 static int verify_ordered(unsigned mode1, const char *name1,
 572                           unsigned mode2, const char *name2,
 573                           struct name_stack *candidates)
 574 {
 575         int len1 = strlen(name1);
 576         int len2 = strlen(name2);
 577         int len = len1 < len2 ? len1 : len2;
 578         unsigned char c1, c2;
 579         int cmp;
 580
 581         cmp = memcmp(name1, name2, len);
 582         if (cmp < 0)
 583                 return 0;
 584         if (cmp > 0)
 585                 return TREE_UNORDERED;
 586
 587         /*
 588          * Ok, the first <len> characters are the same.
 589          * Now we need to order the next one, but turn
 590          * a '\0' into a '/' for a directory entry.
 591          */
 592         c1 = name1[len];
 593         c2 = name2[len];
 594         if (!c1 && !c2)
 595                 /*
 596                  * git-write-tree used to write out a nonsense tree that has
 597                  * entries with the same name, one blob and one tree.  Make
 598                  * sure we do not have duplicate entries.
 599                  */
 600                 return TREE_HAS_DUPS;
 601         if (!c1 && S_ISDIR(mode1))
 602                 c1 = '/';
 603         if (!c2 && S_ISDIR(mode2))
 604                 c2 = '/';
 605
 606         /*
 607          * There can be non-consecutive duplicates due to the implicitly
 608          * added slash, e.g.:
 609          *
 610          *   foo
 611          *   foo.bar
 612          *   foo.bar.baz
 613          *   foo.bar/
 614          *   foo/
 615          *
 616          * Record non-directory candidates (like "foo" and "foo.bar" in
 617          * the example) on a stack and check directory candidates (like
 618          * foo/" and "foo.bar/") against that stack.
 619          */
 620         if (!c1 && is_less_than_slash(c2)) {
 621                 name_stack_push(candidates, name1);
 622         } else if (c2 == '/' && is_less_than_slash(c1)) {
 623                 for (;;) {
 624                         const char *p;
 625                         const char *f_name = name_stack_pop(candidates);
 626
 627                         if (!f_name)
 628                                 break;
 629                         if (!skip_prefix(name2, f_name, &p))
 630                                 continue;
 631                         if (!*p)
 632                                 return TREE_HAS_DUPS;
 633                         if (is_less_than_slash(*p)) {
 634                                 name_stack_push(candidates, f_name);
 635                                 break;
 636                         }
 637                 }
 638         }
 639
 640         return c1 < c2 ? 0 : TREE_UNORDERED;
 641 }
 642
 643 static int fsck_tree(const struct object_id *oid,
 644                      const char *buffer, unsigned long size,
 645                      struct fsck_options *options)
 646 {
 647         int retval = 0;
 648         int has_null_sha1 = 0;
 649         int has_full_path = 0;
 650         int has_empty_name = 0;
 651         int has_dot = 0;
 652         int has_dotdot = 0;
 653         int has_dotgit = 0;
 654         int has_zero_pad = 0;
 655         int has_bad_modes = 0;
 656         int has_dup_entries = 0;
 657         int not_properly_sorted = 0;
 658         struct tree_desc desc;
 659         unsigned o_mode;
 660         const char *o_name;
 661         struct name_stack df_dup_candidates = { NULL };
 662
 663         if (init_tree_desc_gently(&desc, buffer, size)) {
 664                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
 665                 return retval;
 666         }
 667
 668         o_mode = 0;
 669         o_name = NULL;
 670
 671         while (desc.size) {
 672                 unsigned short mode;
 673                 const char *name, *backslash;
 674                 const struct object_id *oid;
 675
 676                 oid = tree_entry_extract(&desc, &name, &mode);
 677
 678                 has_null_sha1 |= is_null_oid(oid);
 679                 has_full_path |= !!strchr(name, '/');
 680                 has_empty_name |= !*name;
 681                 has_dot |= !strcmp(name, ".");
 682                 has_dotdot |= !strcmp(name, "..");
 683                 has_dotgit |= is_hfs_dotgit(name) || is_ntfs_dotgit(name);
 684                 has_zero_pad |= *(char *)desc.buffer == '0';
 685
 686                 if (is_hfs_dotgitmodules(name) || is_ntfs_dotgitmodules(name)) {
 687                         if (!S_ISLNK(mode))
 688                                 oidset_insert(&gitmodules_found, oid);
 689                         else
 690                                 retval += report(options,
 691                                                  oid, OBJ_TREE,
 692                                                  FSCK_MSG_GITMODULES_SYMLINK,
 693                                                  ".gitmodules is a symbolic link");
 694                 }
 695
 696                 if ((backslash = strchr(name, '\\'))) {
 697                         while (backslash) {
 698                                 backslash++;
 699                                 has_dotgit |= is_ntfs_dotgit(backslash);
 700                                 if (is_ntfs_dotgitmodules(backslash)) {
 701                                         if (!S_ISLNK(mode))
 702                                                 oidset_insert(&gitmodules_found, oid);
 703                                         else
 704                                                 retval += report(options, oid, OBJ_TREE,
 705                                                                  FSCK_MSG_GITMODULES_SYMLINK,
 706                                                                  ".gitmodules is a symbolic link");
 707                                 }
 708                                 backslash = strchr(backslash, '\\');
 709                         }
 710                 }
 711
 712                 if (update_tree_entry_gently(&desc)) {
 713                         retval += report(options, oid, OBJ_TREE, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
 714                         break;
 715                 }
 716
 717                 switch (mode) {
 718                 /*
 719                  * Standard modes..
 720                  */
 721                 case S_IFREG | 0755:
 722                 case S_IFREG | 0644:
 723                 case S_IFLNK:
 724                 case S_IFDIR:
 725                 case S_IFGITLINK:
 726                         break;
 727                 /*
 728                  * This is nonstandard, but we had a few of these
 729                  * early on when we honored the full set of mode
 730                  * bits..
 731                  */
 732                 case S_IFREG | 0664:
 733                         if (!options->strict)
 734                                 break;
 735                         /* fallthrough */
 736                 default:
 737                         has_bad_modes = 1;
 738                 }
 739
 740                 if (o_name) {
 741                         switch (verify_ordered(o_mode, o_name, mode, name,
 742                                                &df_dup_candidates)) {
 743                         case TREE_UNORDERED:
 744                                 not_properly_sorted = 1;
 745                                 break;
 746                         case TREE_HAS_DUPS:
 747                                 has_dup_entries = 1;
 748                                 break;
 749                         default:
 750                                 break;
 751                         }
 752                 }
 753
 754                 o_mode = mode;
 755                 o_name = name;
 756         }
 757
 758         name_stack_clear(&df_dup_candidates);
 759
 760         if (has_null_sha1)
 761                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
 762         if (has_full_path)
 763                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
 764         if (has_empty_name)
 765                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
 766         if (has_dot)
 767                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_HAS_DOT, "contains '.'");
 768         if (has_dotdot)
 769                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_HAS_DOTDOT, "contains '..'");
 770         if (has_dotgit)
 771                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
 772         if (has_zero_pad)
 773                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
 774         if (has_bad_modes)
 775                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
 776         if (has_dup_entries)
 777                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
 778         if (not_properly_sorted)
 779                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
 780         return retval;
 781 }
 782
 783 static int verify_headers(const void *data, unsigned long size,
 784                           const struct object_id *oid, enum object_type type,
 785                           struct fsck_options *options)
 786 {
 787         const char *buffer = (const char *)data;
 788         unsigned long i;
 789
 790         for (i = 0; i < size; i++) {
 791                 switch (buffer[i]) {
 792                 case '\0':
 793                         return report(options, oid, type,
 794                                 FSCK_MSG_NUL_IN_HEADER,
 795                                 "unterminated header: NUL at offset %ld", i);
 796                 case '\n':
 797                         if (i + 1 < size && buffer[i + 1] == '\n')
 798                                 return 0;
 799                 }
 800         }
 801
 802         /*
 803          * We did not find double-LF that separates the header
 804          * and the body.  Not having a body is not a crime but
 805          * we do want to see the terminating LF for the last header
 806          * line.
 807          */
 808         if (size && buffer[size - 1] == '\n')
 809                 return 0;
 810
 811         return report(options, oid, type,
 812                 FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
 813 }
 814
 815 static int fsck_ident(const char **ident,
 816                       const struct object_id *oid, enum object_type type,
 817                       struct fsck_options *options)
 818 {
 819         const char *p = *ident;
 820         char *end;
 821
 822         *ident = strchrnul(*ident, '\n');
 823         if (**ident == '\n')
 824                 (*ident)++;
 825
 826         if (*p == '<')
 827                 return report(options, oid, type, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 828         p += strcspn(p, "<>\n");
 829         if (*p == '>')
 830                 return report(options, oid, type, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
 831         if (*p != '<')
 832                 return report(options, oid, type, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
 833         if (p[-1] != ' ')
 834                 return report(options, oid, type, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 835         p++;
 836         p += strcspn(p, "<>\n");
 837         if (*p != '>')
 838                 return report(options, oid, type, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
 839         p++;
 840         if (*p != ' ')
 841                 return report(options, oid, type, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
 842         p++;
 843         if (*p == '0' && p[1] != ' ')
 844                 return report(options, oid, type, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
 845         if (date_overflows(parse_timestamp(p, &end, 10)))
 846                 return report(options, oid, type, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
 847         if ((end == p || *end != ' '))
 848                 return report(options, oid, type, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
 849         p = end + 1;
 850         if ((*p != '+' && *p != '-') ||
 851             !isdigit(p[1]) ||
 852             !isdigit(p[2]) ||
 853             !isdigit(p[3]) ||
 854             !isdigit(p[4]) ||
 855             (p[5] != '\n'))
 856                 return report(options, oid, type, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
 857         p += 6;
 858         return 0;
 859 }
 860
 861 static int fsck_commit(const struct object_id *oid,
 862                        const char *buffer, unsigned long size,
 863                        struct fsck_options *options)
 864 {
 865         struct object_id tree_oid, parent_oid;
 866         unsigned author_count;
 867         int err;
 868         const char *buffer_begin = buffer;
 869         const char *p;
 870
 871         if (verify_headers(buffer, size, oid, OBJ_COMMIT, options))
 872                 return -1;
 873
 874         if (!skip_prefix(buffer, "tree ", &buffer))
 875                 return report(options, oid, OBJ_COMMIT, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
 876         if (parse_oid_hex(buffer, &tree_oid, &p) || *p != '\n') {
 877                 err = report(options, oid, OBJ_COMMIT, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
 878                 if (err)
 879                         return err;
 880         }
 881         buffer = p + 1;
 882         while (skip_prefix(buffer, "parent ", &buffer)) {
 883                 if (parse_oid_hex(buffer, &parent_oid, &p) || *p != '\n') {
 884                         err = report(options, oid, OBJ_COMMIT, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
 885                         if (err)
 886                                 return err;
 887                 }
 888                 buffer = p + 1;
 889         }
 890         author_count = 0;
 891         while (skip_prefix(buffer, "author ", &buffer)) {
 892                 author_count++;
 893                 err = fsck_ident(&buffer, oid, OBJ_COMMIT, options);
 894                 if (err)
 895                         return err;
 896         }
 897         if (author_count < 1)
 898                 err = report(options, oid, OBJ_COMMIT, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
 899         else if (author_count > 1)
 900                 err = report(options, oid, OBJ_COMMIT, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
 901         if (err)
 902                 return err;
 903         if (!skip_prefix(buffer, "committer ", &buffer))
 904                 return report(options, oid, OBJ_COMMIT, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
 905         err = fsck_ident(&buffer, oid, OBJ_COMMIT, options);
 906         if (err)
 907                 return err;
 908         if (memchr(buffer_begin, '\0', size)) {
 909                 err = report(options, oid, OBJ_COMMIT, FSCK_MSG_NUL_IN_COMMIT,
 910                              "NUL byte in the commit object body");
 911                 if (err)
 912                         return err;
 913         }
 914         return 0;
 915 }
 916
 917 static int fsck_tag(const struct object_id *oid, const char *buffer,
 918                     unsigned long size, struct fsck_options *options)
 919 {
 920         struct object_id tagged_oid;
 921         int tagged_type;
 922         return fsck_tag_standalone(oid, buffer, size, options, &tagged_oid,
 923                                    &tagged_type);
 924 }
 925
 926 int fsck_tag_standalone(const struct object_id *oid, const char *buffer,
 927                         unsigned long size, struct fsck_options *options,
 928                         struct object_id *tagged_oid,
 929                         int *tagged_type)
 930 {
 931         int ret = 0;
 932         char *eol;
 933         struct strbuf sb = STRBUF_INIT;
 934         const char *p;
 935
 936         ret = verify_headers(buffer, size, oid, OBJ_TAG, options);
 937         if (ret)
 938                 goto done;
 939
 940         if (!skip_prefix(buffer, "object ", &buffer)) {
 941                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
 942                 goto done;
 943         }
 944         if (parse_oid_hex(buffer, tagged_oid, &p) || *p != '\n') {
 945                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
 946                 if (ret)
 947                         goto done;
 948         }
 949         buffer = p + 1;
 950
 951         if (!skip_prefix(buffer, "type ", &buffer)) {
 952                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
 953                 goto done;
 954         }
 955         eol = strchr(buffer, '\n');
 956         if (!eol) {
 957                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
 958                 goto done;
 959         }
 960         *tagged_type = type_from_string_gently(buffer, eol - buffer, 1);
 961         if (*tagged_type < 0)
 962                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
 963         if (ret)
 964                 goto done;
 965         buffer = eol + 1;
 966
 967         if (!skip_prefix(buffer, "tag ", &buffer)) {
 968                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
 969                 goto done;
 970         }
 971         eol = strchr(buffer, '\n');
 972         if (!eol) {
 973                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
 974                 goto done;
 975         }
 976         strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
 977         if (check_refname_format(sb.buf, 0)) {
 978                 ret = report(options, oid, OBJ_TAG,
 979                              FSCK_MSG_BAD_TAG_NAME,
 980                              "invalid 'tag' name: %.*s",
 981                              (int)(eol - buffer), buffer);
 982                 if (ret)
 983                         goto done;
 984         }
 985         buffer = eol + 1;
 986
 987         if (!skip_prefix(buffer, "tagger ", &buffer)) {
 988                 /* early tags do not contain 'tagger' lines; warn only */
 989                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
 990                 if (ret)
 991                         goto done;
 992         }
 993         else
 994                 ret = fsck_ident(&buffer, oid, OBJ_TAG, options);
 995         if (!*buffer)
 996                 goto done;
 997
 998         if (!starts_with(buffer, "\n")) {
 999                 /*
1000                  * The verify_headers() check will allow
1001                  * e.g. "[...]tagger <tagger>\nsome
1002                  * garbage\n\nmessage" to pass, thinking "some
1003                  * garbage" could be a custom header. E.g. "mktag"
1004                  * doesn't want any unknown headers.
1005                  */
1006                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_EXTRA_HEADER_ENTRY, "invalid format - extra header(s) after 'tagger'");
1007                 if (ret)
1008                         goto done;
1009         }
1010
1011 done:
1012         strbuf_release(&sb);
1013         return ret;
1014 }
1015
1016 /*
1017  * Like builtin/submodule--helper.c's starts_with_dot_slash, but without
1018  * relying on the platform-dependent is_dir_sep helper.
1019  *
1020  * This is for use in checking whether a submodule URL is interpreted as
1021  * relative to the current directory on any platform, since \ is a
1022  * directory separator on Windows but not on other platforms.
1023  */
1024 static int starts_with_dot_slash(const char *str)
1025 {
1026         return str[0] == '.' && (str[1] == '/' || str[1] == '\\');
1027 }
1028
1029 /*
1030  * Like starts_with_dot_slash, this is a variant of submodule--helper's
1031  * helper of the same name with the twist that it accepts backslash as a
1032  * directory separator even on non-Windows platforms.
1033  */
1034 static int starts_with_dot_dot_slash(const char *str)
1035 {
1036         return str[0] == '.' && starts_with_dot_slash(str + 1);
1037 }
1038
1039 static int submodule_url_is_relative(const char *url)
1040 {
1041         return starts_with_dot_slash(url) || starts_with_dot_dot_slash(url);
1042 }
1043
1044 /*
1045  * Count directory components that a relative submodule URL should chop
1046  * from the remote_url it is to be resolved against.
1047  *
1048  * In other words, this counts "../" components at the start of a
1049  * submodule URL.
1050  *
1051  * Returns the number of directory components to chop and writes a
1052  * pointer to the next character of url after all leading "./" and
1053  * "../" components to out.
1054  */
1055 static int count_leading_dotdots(const char *url, const char **out)
1056 {
1057         int result = 0;
1058         while (1) {
1059                 if (starts_with_dot_dot_slash(url)) {
1060                         result++;
1061                         url += strlen("../");
1062                         continue;
1063                 }
1064                 if (starts_with_dot_slash(url)) {
1065                         url += strlen("./");
1066                         continue;
1067                 }
1068                 *out = url;
1069                 return result;
1070         }
1071 }
1072 /*
1073  * Check whether a transport is implemented by git-remote-curl.
1074  *
1075  * If it is, returns 1 and writes the URL that would be passed to
1076  * git-remote-curl to the "out" parameter.
1077  *
1078  * Otherwise, returns 0 and leaves "out" untouched.
1079  *
1080  * Examples:
1081  *   http::https://example.com/repo.git -> 1, https://example.com/repo.git
1082  *   https://example.com/repo.git -> 1, https://example.com/repo.git
1083  *   git://example.com/repo.git -> 0
1084  *
1085  * This is for use in checking for previously exploitable bugs that
1086  * required a submodule URL to be passed to git-remote-curl.
1087  */
1088 static int url_to_curl_url(const char *url, const char **out)
1089 {
1090         /*
1091          * We don't need to check for case-aliases, "http.exe", and so
1092          * on because in the default configuration, is_transport_allowed
1093          * prevents URLs with those schemes from being cloned
1094          * automatically.
1095          */
1096         if (skip_prefix(url, "http::", out) ||
1097             skip_prefix(url, "https::", out) ||
1098             skip_prefix(url, "ftp::", out) ||
1099             skip_prefix(url, "ftps::", out))
1100                 return 1;
1101         if (starts_with(url, "http://") ||
1102             starts_with(url, "https://") ||
1103             starts_with(url, "ftp://") ||
1104             starts_with(url, "ftps://")) {
1105                 *out = url;
1106                 return 1;
1107         }
1108         return 0;
1109 }
1110
1111 static int check_submodule_url(const char *url)
1112 {
1113         const char *curl_url;
1114
1115         if (looks_like_command_line_option(url))
1116                 return -1;
1117
1118         if (submodule_url_is_relative(url) || starts_with(url, "git://")) {
1119                 char *decoded;
1120                 const char *next;
1121                 int has_nl;
1122
1123                 /*
1124                  * This could be appended to an http URL and url-decoded;
1125                  * check for malicious characters.
1126                  */
1127                 decoded = url_decode(url);
1128                 has_nl = !!strchr(decoded, '\n');
1129
1130                 free(decoded);
1131                 if (has_nl)
1132                         return -1;
1133
1134                 /*
1135                  * URLs which escape their root via "../" can overwrite
1136                  * the host field and previous components, resolving to
1137                  * URLs like https::example.com/submodule.git and
1138                  * https:///example.com/submodule.git that were
1139                  * susceptible to CVE-2020-11008.
1140                  */
1141                 if (count_leading_dotdots(url, &next) > 0 &&
1142                     (*next == ':' || *next == '/'))
1143                         return -1;
1144         }
1145
1146         else if (url_to_curl_url(url, &curl_url)) {
1147                 struct credential c = CREDENTIAL_INIT;
1148                 int ret = 0;
1149                 if (credential_from_url_gently(&c, curl_url, 1) ||
1150                     !*c.host)
1151                         ret = -1;
1152                 credential_clear(&c);
1153                 return ret;
1154         }
1155
1156         return 0;
1157 }
1158
1159 struct fsck_gitmodules_data {
1160         const struct object_id *oid;
1161         struct fsck_options *options;
1162         int ret;
1163 };
1164
1165 static int fsck_gitmodules_fn(const char *var, const char *value, void *vdata)
1166 {
1167         struct fsck_gitmodules_data *data = vdata;
1168         const char *subsection, *key;
1169         size_t subsection_len;
1170         char *name;
1171
1172         if (parse_config_key(var, "submodule", &subsection, &subsection_len, &key) < 0 ||
1173             !subsection)
1174                 return 0;
1175
1176         name = xmemdupz(subsection, subsection_len);
1177         if (check_submodule_name(name) < 0)
1178                 data->ret |= report(data->options,
1179                                     data->oid, OBJ_BLOB,
1180                                     FSCK_MSG_GITMODULES_NAME,
1181                                     "disallowed submodule name: %s",
1182                                     name);
1183         if (!strcmp(key, "url") && value &&
1184             check_submodule_url(value) < 0)
1185                 data->ret |= report(data->options,
1186                                     data->oid, OBJ_BLOB,
1187                                     FSCK_MSG_GITMODULES_URL,
1188                                     "disallowed submodule url: %s",
1189                                     value);
1190         if (!strcmp(key, "path") && value &&
1191             looks_like_command_line_option(value))
1192                 data->ret |= report(data->options,
1193                                     data->oid, OBJ_BLOB,
1194                                     FSCK_MSG_GITMODULES_PATH,
1195                                     "disallowed submodule path: %s",
1196                                     value);
1197         if (!strcmp(key, "update") && value &&
1198             parse_submodule_update_type(value) == SM_UPDATE_COMMAND)
1199                 data->ret |= report(data->options, data->oid, OBJ_BLOB,
1200                                     FSCK_MSG_GITMODULES_UPDATE,
1201                                     "disallowed submodule update setting: %s",
1202                                     value);
1203         free(name);
1204
1205         return 0;
1206 }
1207
1208 static int fsck_blob(const struct object_id *oid, const char *buf,
1209                      unsigned long size, struct fsck_options *options)
1210 {
1211         struct fsck_gitmodules_data data;
1212         struct config_options config_opts = { 0 };
1213
1214         if (!oidset_contains(&gitmodules_found, oid))
1215                 return 0;
1216         oidset_insert(&gitmodules_done, oid);
1217
1218         if (object_on_skiplist(options, oid))
1219                 return 0;
1220
1221         if (!buf) {
1222                 /*
1223                  * A missing buffer here is a sign that the caller found the
1224                  * blob too gigantic to load into memory. Let's just consider
1225                  * that an error.
1226                  */
1227                 return report(options, oid, OBJ_BLOB,
1228                               FSCK_MSG_GITMODULES_LARGE,
1229                               ".gitmodules too large to parse");
1230         }
1231
1232         data.oid = oid;
1233         data.options = options;
1234         data.ret = 0;
1235         config_opts.error_action = CONFIG_ERROR_SILENT;
1236         if (git_config_from_mem(fsck_gitmodules_fn, CONFIG_ORIGIN_BLOB,
1237                                 ".gitmodules", buf, size, &data, &config_opts))
1238                 data.ret |= report(options, oid, OBJ_BLOB,
1239                                    FSCK_MSG_GITMODULES_PARSE,
1240                                    "could not parse gitmodules blob");
1241
1242         return data.ret;
1243 }
1244
1245 int fsck_object(struct object *obj, void *data, unsigned long size,
1246         struct fsck_options *options)
1247 {
1248         if (!obj)
1249                 return report(options, NULL, OBJ_NONE, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
1250
1251         if (obj->type == OBJ_BLOB)
1252                 return fsck_blob(&obj->oid, data, size, options);
1253         if (obj->type == OBJ_TREE)
1254                 return fsck_tree(&obj->oid, data, size, options);
1255         if (obj->type == OBJ_COMMIT)
1256                 return fsck_commit(&obj->oid, data, size, options);
1257         if (obj->type == OBJ_TAG)
1258                 return fsck_tag(&obj->oid, data, size, options);
1259
1260         return report(options, &obj->oid, obj->type,
1261                       FSCK_MSG_UNKNOWN_TYPE,
1262                       "unknown type '%d' (internal fsck error)",
1263                       obj->type);
1264 }
1265
1266 int fsck_error_function(struct fsck_options *o,
1267                         const struct object_id *oid,
1268                         enum object_type object_type,
1269                         int msg_type, const char *message)
1270 {
1271         if (msg_type == FSCK_WARN) {
1272                 warning("object %s: %s", fsck_describe_object(o, oid), message);
1273                 return 0;
1274         }
1275         error("object %s: %s", fsck_describe_object(o, oid), message);
1276         return 1;
1277 }
1278
1279 void register_found_gitmodules(const struct object_id *oid)
1280 {
1281         oidset_insert(&gitmodules_found, oid);
1282 }
1283
1284 int fsck_finish(struct fsck_options *options)
1285 {
1286         int ret = 0;
1287         struct oidset_iter iter;
1288         const struct object_id *oid;
1289
1290         oidset_iter_init(&gitmodules_found, &iter);
1291         while ((oid = oidset_iter_next(&iter))) {
1292                 enum object_type type;
1293                 unsigned long size;
1294                 char *buf;
1295
1296                 if (oidset_contains(&gitmodules_done, oid))
1297                         continue;
1298
1299                 buf = read_object_file(oid, &type, &size);
1300                 if (!buf) {
1301                         if (is_promisor_object(oid))
1302                                 continue;
1303                         ret |= report(options,
1304                                       oid, OBJ_BLOB,
1305                                       FSCK_MSG_GITMODULES_MISSING,
1306                                       "unable to read .gitmodules blob");
1307                         continue;
1308                 }
1309
1310                 if (type == OBJ_BLOB)
1311                         ret |= fsck_blob(oid, buf, size, options);
1312                 else
1313                         ret |= report(options,
1314                                       oid, type,
1315                                       FSCK_MSG_GITMODULES_BLOB,
1316                                       "non-blob found at .gitmodules");
1317                 free(buf);
1318         }
1319
1320
1321         oidset_clear(&gitmodules_found);
1322         oidset_clear(&gitmodules_done);
1323         return ret;
1324 }
1325
1326 int fsck_config_internal(const char *var, const char *value, void *cb,
1327                          struct fsck_options *options)
1328 {
1329         if (strcmp(var, "fsck.skiplist") == 0) {
1330                 const char *path;
1331                 struct strbuf sb = STRBUF_INIT;
1332
1333                 if (git_config_pathname(&path, var, value))
1334                         return 1;
1335                 strbuf_addf(&sb, "skiplist=%s", path);
1336                 free((char *)path);
1337                 fsck_set_msg_types(options, sb.buf);
1338                 strbuf_release(&sb);
1339                 return 0;
1340         }
1341
1342         if (skip_prefix(var, "fsck.", &var)) {
1343                 fsck_set_msg_type(options, var, value);
1344                 return 0;
1345         }
1346
1347         return git_default_config(var, value, cb);
1348 }