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