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2026-08-24Merge branch 'js/pack-objects-delta-size-t'Junio C Hamano1-2/+2
The 'pack-objects' and delta-encoding code paths have been updated to use 'size_t' instead of 'unsigned long' for object sizes and offset limits, avoiding potential truncation issues on 64-bit Windows. * js/pack-objects-delta-size-t: packfile: widen `unpack_object_header_buffer()` to `size_t` git-zlib: widen `git_deflate_bound()` to `size_t` t/helper/test-pack-deltas: widen `do_compress()`'s maxsize local to `size_t` http-push: widen `start_put()`'s size local from `ssize_t` to `size_t` diff: widen `deflate_it()`'s bound local from int to `size_t` archive-zip: widen `zlib_deflate_raw()`'s maxsize local to `size_t` packfile, git-zlib: widen `use_pack()` and zstream avail fields to `size_t` delta: widen `create_delta()` and `diff_delta()` to `size_t` pack-objects: widen `mem_usage` and `try_delta()`'s out-param to `size_t` pack-objects: widen `free_unpacked()` return to `size_t` pack-objects: widen delta-cache accounting to `size_t` delta: widen `create_delta_index()` parameter to `size_t` diff-delta: widen `struct delta_index`' size fields to `size_t`
2026-08-13packfile, git-zlib: widen `use_pack()` and zstream avail fields to `size_t`Johannes Schindelin1-2/+2
Bundling the two widenings: four call sites pass `&stream.avail_in` directly to `use_pack()`, and widening either type fencepost alone would force a bridge variable at each. Doing both together is the simpler end state and is the prerequisite for the `do_compress()` widening in the next commit, which is what lets `write_no_reuse_object()` lose its last `cast_size_t_to_ulong()` shim. The unsigned-long locals widened at the other `use_pack()` callers (avail / remaining / left) hold pack-window sizes bounded by `core.packedGitWindowSize`, so the change is type consistency rather than a new >4GB capability. `git_zstream.avail_in`/`avail_out` likewise reach zlib's `uInt` fields only after `zlib_buf_cap()`'s 1 GiB cap, so the wrapper already accepted `size_t`-shaped inputs in practice. Assisted-by: Opus 4.7 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-08-05odb/streaming: rename `struct odb_read_stream`Patrick Steinhardt1-2/+2
Rename `struct odb_read_stream` to just `struct odb_stream`. This prepares for unification of the two different types of streams, as these provide the same functionality with the preceding refactorings. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-07-07hash: use git_hash_init() consistentlyJeff King1-1/+1
We'd like to add more logic to git_hash_init(), but many callers skip it and call algop->init_fn() directly. Let's make sure we're consistently using the wrapper by adding a coccinelle rule. Besides the coccinelle file itself, this is a purely mechanical conversion based on the patch it generates. There should be no bare init_fn() calls left (except for the one in the wrapper). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-06-15packfile: widen unpack_entry()'s size out-parameter to size_tJohannes Schindelin1-3/+2
The topic `js/objects-larger-than-4gb-on-windows` widened the streaming, index-pack and unpack-objects paths to `size_t` but deliberately stopped at the in-memory `unpack_entry()` cascade, which still hands back the unpacked size through `unsigned long *`. On Windows that boundary truncates above 4 GiB because that data type is only 32 bits wide on that platform. Widen the code path. Except `packed_object_info_with_index_pos()`: It cannot yet pass `oi->sizep` directly because the field is still `unsigned long *`; bridge it with a `size_t` temporary that narrows back, and let a later commit drop the bridge once the field is wide too. `gfi_unpack_entry()` keeps its narrow signature because fast-import tracks sizes through `unsigned long` everywhere it crosses subsystem boundaries, keeping its signature allows the scope of this commit to be somewhat reasonable, still. Assisted-by: Opus 4.7 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-05-09odb, packfile: use size_t for streaming object sizesJohannes Schindelin1-2/+4
The odb_read_stream structure uses unsigned long for the size field, which is 32-bit on Windows even in 64-bit builds. When streaming objects larger than 4GB, the size would be truncated to zero or an incorrect value, resulting in empty files being written to disk. Change the size field in odb_read_stream to size_t and introduce unpack_object_header_sz() to return sizes via size_t pointer. Since object_info.sizep remains unsigned long for API compatibility, use temporary variables where the types differ, with comments noting the truncation limitation for code paths that still use unsigned long. Widening the producers to size_t in this way introduces a handful of silent size_t -> unsigned long narrowings on Windows, all in builtin/pack-objects.c, where the consumers are still typed unsigned long. Make those narrowings explicit with cast_size_t_to_ulong() so they assert loudly the moment an object actually exceeds ULONG_MAX bytes: - oe_get_size_slow() returns unsigned long but holds a size_t locally; cast at the return. - write_reuse_object() passes a size_t into check_pack_inflate(), whose expect parameter is unsigned long; cast at the call. - check_object() routes a size_t through SET_SIZE() and SET_DELTA_SIZE(), both of which take unsigned long via oe_set_size() / oe_set_delta_size(); cast at the three call sites in the OBJ_OFS_DELTA / OBJ_REF_DELTA branches and in the non-delta default arm. The cast-only treatment is deliberately a stop-gap. Properly widening oe_set_size, oe_get_size_slow's return type, check_pack_inflate's expect parameter, object_info.sizep, patch_delta, and the OE_SIZE_BITS bit-fields cascades into a series that is too large to be reviewable, so the proper widening is deferred to a follow-up topic. Until then, cast_size_t_to_ulong() at least makes the truncation explicit at the source: it documents the boundary, and on a 64-bit non-Windows platform it is a no-op. This was originally authored by LordKiRon <https://github.com/LordKiRon>, who preferred not to reveal their real name and therefore agreed that I take over authorship. Helped-by: Torsten Bögershausen <tboegi@web.de> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-03-23builtin/fsck: stop using `the_repository` when checking packed objectsPatrick Steinhardt1-3/+4
We implicitly rely on `the_repository` when checking objects part of a packfile. These objects are iterated over via `verify_pack()`, which is provided by the packfile subsystem, and a callback function is then invoked for each of the objects in that specific pack. Unfortunately, it is not possible to provide a payload to the callback function. Refactor `verify_pack()` to accept a payload that is passed through to the callback so that we can inject the repository and get rid of the use of `the_repository`. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-02-23pack-check: fix verification of large objectsPatrick Steinhardt1-1/+1
It was reported [1] that git-fsck(1) may sometimes run into an infinite loop when processing packfiles. This bug was bisected to c31bad4f7d (packfile: track packs via the MRU list exclusively, 2025-10-30), which refactored our lsit of packfiles to only be tracked via an MRU list, exclusively. This isn't entirely surprising: any caller that iterates through the list of packfiles and then hits `find_pack_entry()`, for example because they read an object from it, may cause the MRU list to be updated. And if the caller is unlucky, this may cause the mentioned infinite loop. While this mechanism is somewhat fragile, it is still surprising that we encounter it when verifying the packfile. We iterate through objects in a given pack one by one and then read them via their offset, and doing this shouldn't ever end up in `find_pack_entry()`. But there is an edge case here: when the object in question is a blob bigger than "core.largeFileThreshold", then we will be careful to not read it into memory. Instead, we read it via an object stream by calling `odb_read_object_stream()`, and that function will perform an object lookup via `odb_read_object_info()`. So in the case where there are at least two blobs in two different packfiles, and both of these blobs exceed "core.largeFileThreshold", then we'll run into an infinite loop because we'll always update the MRU. We could fix this by improving `repo_for_each_pack()` to not update the MRU, and this would address the issue. But the fun part is that using `odb_read_object_stream()` is the wrong thing to do in the first place: it may open _any_ instance of this object, so we ultimately cannot be sure that we even verified the object in our given packfile. Fix this bug by creating the object stream for the packed object directly via `packfile_read_object_stream()`. Add a test that would have caused the infinite loop. [1]: <20260222183710.2963424-1-sandals@crustytoothpaste.net> Reported-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-02-23object-file: adapt `stream_object_signature()` to take a streamPatrick Steinhardt1-3/+9
The function `stream_object_signature()` is responsible for verifying whether the given object ID matches the actual hash of the object's contents. In contrast to `check_object_signature()` it does so in a streaming fashion so that we don't have to load the full object into memory. In a subsequent commit we'll want to adapt one of its callsites to pass a preconstructed stream. Prepare for this by accepting a stream as input that the caller needs to assemble. While at it, improve the error reporting in `parse_object_with_flags()` to tell apart the two failure modes. Helped-by: Jeff King <peff@peff.net> Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-07-01object-store: rename files to "odb.{c,h}"Patrick Steinhardt1-1/+1
In the preceding commits we have renamed the structures contained in "object-store.h" to `struct object_database` and `struct odb_backend`. As such, the code files "object-store.{c,h}" are confusingly named now. Rename them to "odb.{c,h}" accordingly. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-04-15object-store: merge "object-store-ll.h" and "object-store.h"Patrick Steinhardt1-1/+1
The "object-store-ll.h" header has been introduced to keep transitive header dependendcies and compile times at bay. Now that we have created a new "object-store.c" file though we can easily move the last remaining additional bit of "object-store.h", the `odb_path_map`, out of the header. Do so. As the "object-store.h" header is now equivalent to its low-level alternative we drop the latter and inline it into the former. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-03-10pack-check: stop depending on `the_repository`Patrick Steinhardt1-6/+5
There are multiple sites in "pack-check.c" where we use the global `the_repository` variable, either explicitly or implicitly by using `the_hash_algo`. In all of those cases we already have a repository available in the calling context though. Refactor the code to instead use the caller-provided repository and remove the `USE_THE_REPOSITORY_VARIABLE` define. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-03-10environment: move access to "core.bigFileThreshold" into repo settingsPatrick Steinhardt1-1/+2
The "core.bigFileThreshold" setting is stored in a global variable and populated via `git_default_core_config()`. This may cause issues in the case where one is handling multiple different repositories in a single process with different values for that config key, as we may or may not see the correct value in that case. Furthermore, global state blocks our path towards libification. Refactor the code so that we instead store the value in `struct repo_settings`, where the value is computed as-needed and cached. Note that this change requires us to adapt one test in t1050 that verifies that we die when parsing an invalid "core.bigFileThreshold" value. The exercised Git command doesn't use the value at all, and thus it won't hit the new code path that parses the value. This is addressed by using git-hash-object(1) instead, which does read the value. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-03-10csum-file: stop depending on `the_repository`Patrick Steinhardt1-1/+1
There are multiple sites in "csum-file.c" where we use the global `the_repository` variable, either explicitly or implicitly by using `the_hash_algo`. Refactor the code to stop using `the_repository` by adapting functions to receive required data as parameters. Adapt callsites accordingly by either using `the_repository->hash_algo`, or by using a context-provided hash algorithm in case the subsystem already got rid of its dependency on `the_repository`. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-31global: adapt callers to use generic hash context helpersPatrick Steinhardt1-2/+2
Adapt callers to use generic hash context helpers instead of using the hash algorithm to update them. This makes the callsites easier to reason about and removes the possibility that the wrong hash algorithm is used to update the hash context's state. And as a nice side effect this also gets rid of a bunch of users of `the_hash_algo`. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-31hash: stop typedeffing the hash contextPatrick Steinhardt1-1/+1
We generally avoid using `typedef` in the Git codebase. One exception though is the `git_hash_ctx`, likely because it used to be a union rather than a struct until the preceding commit refactored it. But now that it is a normal `struct` there isn't really a need for a typedef anymore. Drop the typedef and adapt all callers accordingly. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-06global: mark code units that generate warnings with `-Wsign-compare`Patrick Steinhardt1-0/+1
Mark code units that generate warnings with `-Wsign-compare`. This allows for a structured approach to get rid of all such warnings over time in a way that can be easily measured. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-14global: introduce `USE_THE_REPOSITORY_VARIABLE` macroPatrick Steinhardt1-0/+2
Use of the `the_repository` variable is deprecated nowadays, and we slowly but steadily convert the codebase to not use it anymore. Instead, callers should be passing down the repository to work on via parameters. It is hard though to prove that a given code unit does not use this variable anymore. The most trivial case, merely demonstrating that there is no direct use of `the_repository`, is already a bit of a pain during code reviews as the reviewer needs to manually verify claims made by the patch author. The bigger problem though is that we have many interfaces that implicitly rely on `the_repository`. Introduce a new `USE_THE_REPOSITORY_VARIABLE` macro that allows code units to opt into usage of `the_repository`. The intent of this macro is to demonstrate that a certain code unit does not use this variable anymore, and to keep it from new dependencies on it in future changes, be it explicit or implicit For now, the macro only guards `the_repository` itself as well as `the_hash_algo`. There are many more known interfaces where we have an implicit dependency on `the_repository`, but those are not guarded at the current point in time. Over time though, we should start to add guards as required (or even better, just remove them). Define the macro as required in our code units. As expected, most of our code still relies on the global variable. Nearly all of our builtins rely on the variable as there is no way yet to pass `the_repository` to their entry point. For now, declare the macro in "biultin.h" to keep the required changes at least a little bit more contained. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-14hash: require hash algorithm in `hasheq()`, `hashcmp()` and `hashclr()`Patrick Steinhardt1-2/+3
Many of our hash functions have two variants, one receiving a `struct git_hash_algo` and one that derives it via `the_repository`. Adapt all of those functions to always require the hash algorithm as input and drop the variants that do not accept one. As those functions are now independent of `the_repository`, we can move them from "hash.h" to "hash-ll.h". Note that both in this and subsequent commits in this series we always just pass `the_repository->hash_algo` as input even if it is obvious that there is a repository in the context that we should be using the hash from instead. This is done to be on the safe side and not introduce any regressions. All callsites should eventually be amended to use a repo passed via parameters, but this is outside the scope of this patch series. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-26treewide: remove unnecessary includes in source filesElijah Newren1-1/+0
Each of these were checked with gcc -E -I. ${SOURCE_FILE} | grep ${HEADER_FILE} to ensure that removing the direct inclusion of the header actually resulted in that header no longer being included at all (i.e. that no other header pulled it in transitively). ...except for a few cases where we verified that although the header was brought in transitively, nothing from it was directly used in that source file. These cases were: * builtin/credential-cache.c * builtin/pull.c * builtin/send-pack.c Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-06-21object-store-ll.h: split this header out of object-store.hElijah Newren1-1/+1
The vast majority of files including object-store.h did not need dir.h nor khash.h. Split the header into two files, and let most just depend upon object-store-ll.h, while letting the two callers that need it depend on the full object-store.h. After this patch: $ git grep -h include..object-store | sort | uniq -c 2 #include "object-store.h" 129 #include "object-store-ll.h" Diff best viewed with `--color-moved`. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-11treewide: remove cache.h inclusion due to object-file.h changesElijah Newren1-1/+1
Signed-off-by: Elijah Newren <newren@gmail.com> Acked-by: Calvin Wan <calvinwan@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-11object-file.h: move declarations for object-file.c functions from cache.hElijah Newren1-0/+1
Signed-off-by: Elijah Newren <newren@gmail.com> Acked-by: Calvin Wan <calvinwan@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-21environment.h: move declarations for environment.c functions from cache.hElijah Newren1-0/+1
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-23cache.h: remove dependence on hex.h; make other files include it explicitlyElijah Newren1-0/+1
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-25object-file API: have hash_object_file() take "enum object_type"Ævar Arnfjörð Bjarmason1-1/+1
Change the hash_object_file() function to take an "enum object_type". Since a preceding commit all of its callers are passing either "{commit,tree,blob,tag}_type", or the result of a call to type_name(), the parse_object() caller that would pass NULL is now using stream_object_signature(). Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-25object-file API: split up and simplify check_object_signature()Ævar Arnfjörð Bjarmason1-3/+6
Split up the check_object_signature() function into that non-streaming version (it accepts an already filled "buf"), and a new stream_object_signature() which will retrieve the object from storage, and hash it on-the-fly. All of the callers of check_object_signature() were effectively calling two different functions, if we go by cyclomatic complexity. I.e. they'd either take the early "if (map)" branch and return early, or not. This has been the case since the "if (map)" condition was added in 090ea12671b (parse_object: avoid putting whole blob in core, 2012-03-07). We can then further simplify the resulting check_object_signature() function since only one caller wanted to pass a non-NULL "buf" and a non-NULL "real_oidp". That "read_loose_object()" codepath used by "git fsck" can instead use hash_object_file() followed by oideq(). Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-25object API users + docs: check <0, not !0 with check_object_signature()Ævar Arnfjörð Bjarmason1-1/+1
Change those users of the object API that misused check_object_signature() by assuming it returned any non-zero when the OID didn't match the expected value to check <0 instead. In practice all of this code worked before, but it wasn't consistent with rest of the users of the API. Let's also clarify what the <0 return value means in API docs. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-25Merge branch 'ab/fsck-unexpected-type'Junio C Hamano1-1/+2
"git fsck" has been taught to report mismatch between expected and actual types of an object better. * ab/fsck-unexpected-type: fsck: report invalid object type-path combinations fsck: don't hard die on invalid object types object-file.c: stop dying in parse_loose_header() object-file.c: return ULHR_TOO_LONG on "header too long" object-file.c: use "enum" return type for unpack_loose_header() object-file.c: simplify unpack_loose_short_header() object-file.c: make parse_loose_header_extended() public object-file.c: return -1, not "status" from unpack_loose_header() object-file.c: don't set "typep" when returning non-zero cat-file tests: test for current --allow-unknown-type behavior cat-file tests: add corrupt loose object test cat-file tests: test for missing/bogus object with -t, -s and -p cat-file tests: move bogus_* variable declarations earlier fsck tests: test for garbage appended to a loose object fsck tests: test current hash/type mismatch behavior fsck tests: refactor one test to use a sub-repo fsck tests: add test for fsck-ing an unknown type
2021-10-01fsck: report invalid object type-path combinationsÆvar Arnfjörð Bjarmason1-1/+2
Improve the error that's emitted in cases where we find a loose object we parse, but which isn't at the location we expect it to be. Before this change we'd prefix the error with a not-a-OID derived from the path at which the object was found, due to an emergent behavior in how we'd end up with an "OID" in these codepaths. Now we'll instead say what object we hashed, and what path it was found at. Before this patch series e.g.: $ git hash-object --stdin -w -t blob </dev/null e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 $ mv objects/e6/ objects/e7 Would emit ("[...]" used to abbreviate the OIDs): git fsck error: hash mismatch for ./objects/e7/9d[...] (expected e79d[...]) error: e79d[...]: object corrupt or missing: ./objects/e7/9d[...] Now we'll instead emit: error: e69d[...]: hash-path mismatch, found at: ./objects/e7/9d[...] Furthermore, we'll do the right thing when the object type and its location are bad. I.e. this case: $ git hash-object --stdin -w -t garbage --literally </dev/null 8315a83d2acc4c174aed59430f9a9c4ed926440f $ mv objects/83 objects/84 As noted in an earlier commits we'd simply die early in those cases, until preceding commits fixed the hard die on invalid object type: $ git fsck fatal: invalid object type Now we'll instead emit sensible error messages: $ git fsck error: 8315[...]: hash-path mismatch, found at: ./objects/84/15[...] error: 8315[...]: object is of unknown type 'garbage': ./objects/84/15[...] In both fsck.c and object-file.c we're using null_oid as a sentinel value for checking whether we got far enough to be certain that the issue was indeed this OID mismatch. We need to add the "object corrupt or missing" special-case to deal with cases where read_loose_object() will return an error before completing check_object_signature(), e.g. if we have an error in unpack_loose_rest() because we find garbage after the valid gzip content: $ git hash-object --stdin -w -t blob </dev/null e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 $ chmod 755 objects/e6/9de29bb2d1d6434b8b29ae775ad8c2e48c5391 $ echo garbage >>objects/e6/9de29bb2d1d6434b8b29ae775ad8c2e48c5391 $ git fsck error: garbage at end of loose object 'e69d[...]' error: unable to unpack contents of ./objects/e6/9d[...] error: e69d[...]: object corrupt or missing: ./objects/e6/9d[...] There is currently some weird messaging in the edge case when the two are combined, i.e. because we're not explicitly passing along an error state about this specific scenario from check_stream_oid() via read_loose_object() we'll end up printing the null OID if an object is of an unknown type *and* it can't be unpacked by zlib, e.g.: $ git hash-object --stdin -w -t garbage --literally </dev/null 8315a83d2acc4c174aed59430f9a9c4ed926440f $ chmod 755 objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f $ echo garbage >>objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f $ /usr/bin/git fsck fatal: invalid object type $ ~/g/git/git fsck error: garbage at end of loose object '8315a83d2acc4c174aed59430f9a9c4ed926440f' error: unable to unpack contents of ./objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f error: 8315a83d2acc4c174aed59430f9a9c4ed926440f: object corrupt or missing: ./objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f error: 0000000000000000000000000000000000000000: object is of unknown type 'garbage': ./objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f [...] I think it's OK to leave that for future improvements, which would involve enum-ifying more error state as we've done with "enum unpack_loose_header_result" in preceding commits. In these increasingly more obscure cases the worst that can happen is that we'll get slightly nonsensical or inapplicable error messages. There's other such potential edge cases, all of which might produce some confusing messaging, but still be handled correctly as far as passing along errors goes. E.g. if check_object_signature() returns and oideq(real_oid, null_oid()) is true, which could happen if it returns -1 due to the read_istream() call having failed. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-06-28csum-file: introduce checksum_valid()Taylor Blau1-10/+1
Introduce a new function which checks the validity of a file's trailing checksum. This is similar to hashfd_check(), but different since it is intended to be used by callers who aren't writing the same data (like `git index-pack --verify`), but who instead want to validate the integrity of data that they are reading. Rewrite the first of two callers which could benefit from this new function in pack-check.c. Subsequent callers will be added in the following patches. Helped-by: Jeff King <peff@peff.net> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-11-16fsck: correctly compute checksums on idx files larger than 4GBJeff King1-4/+4
When checking the trailing checksum hash of a .idx file, we pass the whole buffer (minus the trailing hash) into a single call to the_hash_algo->update_fn(). But we cast it to an "unsigned int". This comes from c4001d92be (Use off_t when we really mean a file offset., 2007-03-06). That commit started storing the index_size variable as an off_t, but our mozilla-sha1 implementation from the time was limited to a smaller size. Presumably the cast was a way of annotating that we expected .idx files to be small, and so we didn't need to loop (as we do for arbitrarily-large .pack files). Though as an aside it was still wrong, because the mozilla function actually took a signed int. These days our hash-update functions are defined to take a size_t, so we can pass the whole buffer in directly. The cast is actually causing a buggy truncation! While we're here, though, let's drop the confusing off_t variable in the first place. We're getting the size not from the filesystem anyway, but from p->index_size, which is a size_t. In fact, we can make the code a bit more readable by dropping our local variable duplicating p->index_size, and instead have one that stores the size of the actual index data, minus the trailing hash. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-11-16compute pack .idx byte offsets using size_tJeff King1-1/+1
A pack and its matching .idx file are limited to 2^32 objects, because the pack format contains a 32-bit field to store the number of objects. Hence we use uint32_t in the code. But the byte count of even a .idx file can be much larger than that, because it stores at least a hash and an offset for each object. So using SHA-1, a v2 .idx file will cross the 4GB boundary at 153,391,650 objects. This confuses load_idx(), which computes the minimum size like this: unsigned long min_size = 8 + 4*256 + nr*(hashsz + 4 + 4) + hashsz + hashsz; Even though min_size will be big enough on most 64-bit platforms, the actual arithmetic is done as a uint32_t, resulting in a truncation. We actually exceed that min_size, but then we do: unsigned long max_size = min_size; if (nr) max_size += (nr - 1)*8; to account for the variable-sized table. That computation doesn't overflow quite so low, but with the truncation for min_size, we end up with a max_size that is much smaller than our actual size. So we complain that the idx is invalid, and can't find any of its objects. We can fix this case by casting "nr" to a size_t, which will do the multiplication in 64-bits (assuming you're on a 64-bit platform; this will never work on a 32-bit system since we couldn't map the whole .idx anyway). Likewise, we don't have to worry about further additions, because adding a smaller number to a size_t will convert the other side to a size_t. A few notes: - obviously we could just declare "nr" as a size_t in the first place (and likewise, packed_git.num_objects). But it's conceptually a uint32_t because of the on-disk format, and we correctly treat it that way in other contexts that don't need to compute byte offsets (e.g., iterating over the set of objects should and generally does use a uint32_t). Switching to size_t would make all of those other cases look wrong. - it could be argued that the proper type is off_t to represent the file offset. But in practice the .idx file must fit within memory, because we mmap the whole thing. And the rest of the code (including the idx_size variable we're comparing against) uses size_t. - we'll add the same cast to the max_size arithmetic line. Even though we're adding to a larger type, which will convert our result, the multiplication is still done as a 32-bit value and can itself overflow. I didn't check this with my test case, since it would need an even larger pack (~530M objects), but looking at compiler output shows that it works this way. The standard should agree, but I couldn't find anything explicit in 6.3.1.8 ("usual arithmetic conversions"). The case in load_idx() was the most immediate one that I was able to trigger. After fixing it, looking up actual objects (including the very last one in sha1 order) works in a test repo with 153,725,110 objects. That's because bsearch_hash() works with uint32_t entry indices, and the actual byte access: int cmp = hashcmp(table + mi * stride, sha1); is done with "stride" as a size_t, causing the uint32_t "mi" to be promoted to a size_t. This is the way most code will access the index data. However, I audited all of the other byte-wise accesses of packed_git.index_data, and many of the others are suspect (they are similar to the max_size one, where we are adding to a properly sized offset or directly to a pointer, but the multiplication in the sub-expression can overflow). I didn't trigger any of these in practice, but I believe they're potential problems, and certainly adding in the cast is not going to hurt anything here. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-24pack-check: push oid lookup into loopJeff King1-13/+10
When we're checking a pack with fsck or verify-pack, we first sort the idx entries by offset, since accessing them in pack order is more efficient. To do so, we loop over them and fill in an array of structs with the offset, object_id, and index position of each, sort the result, and only then do we iterate over the sorted array and process each entry. In order to avoid the memory cost of storing the hash of each object, we just store a pointer into the copy in the mmap'd pack index file. To keep that property even as the rest of the code converted to "struct object_id", commit 9fd750461b (Convert the verify_pack callback to struct object_id, 2017-05-06) introduced a union in order to type-pun the pointer-to-hash into an object_id struct. But we can make this even simpler by observing that the sort operation doesn't need the object id at all! We only need them one at a time while we actually process each entry. So we can just omit the oid from the struct entirely and load it on the fly into a local variable in the second loop. This gets rid of the type-punning, and lets us directly use the more type-safe nth_packed_object_id(), simplifying the code. And as a bonus, it saves 8 bytes of memory per object. Note that this does mean we'll do the offset lookup for each object before the oid lookup. The oid lookup has more safety checks in it (e.g., for looking past p->num_objects) which in theory protected the offset lookup. But since violating those checks was already a BUG() condition (as described in the previous commit), it's not worth worrying about. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-24pack-check: convert "internal error" die to a BUG()Jeff King1-1/+2
If we fail to load the oid from the index of a packfile, we'll die() with an "internal error". But this should never happen: we'd fail here only if the idx needed to be lazily opened (but we've already opened it) or if we asked for an out-of-range index (but we're iterating using the same count that we'd check the range against). A corrupted index might have a bogus count (e.g., too large for its size), but we'd have complained and aborted already when opening the index initially. While we're here, we can add a few details so that if this bug ever _does_ trigger, we'll have a bit more information. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-31sha1-file: allow check_object_signature() to handle any repoMatheus Tavares1-1/+1
Some callers of check_object_signature() can work on arbitrary repositories, but the repo does not get passed to this function. Instead, the_repository is always used internally. To fix possible inconsistencies, allow the function to receive a struct repository and make those callers pass on the repo being handled. Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-31pack-check: use given repo's hash_algo at verify_packfile()Matheus Tavares1-5/+5
At verify_packfile(), use the git_hash_algo from the provided repository instead of the_hash_algo, for consistency. Like the previous patch, this shouldn't bring any behavior changes, since this function is currently only receiving the_repository. Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-12pack-check.c: remove the_repository referencesNguyễn Thái Ngọc Duy1-4/+5
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-29convert "hashcmp() != 0" to "!hasheq()"Jeff King1-3/+3
This rounds out the previous three patches, covering the inequality logic for the "hash" variant of the functions. As with the previous three, the accompanying code changes are the mechanical result of applying the coccinelle patch; see those patches for more discussion. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-26packfile: add repository argument to unpack_entryStefan Beller1-1/+2
Add a repository argument to allow the callers of unpack_entry to be more specific about which repository to act on. This is a small mechanical change; it doesn't change the implementation to handle repositories other than the_repository yet. As with the previous commits, use a macro to catch callers passing a repository other than the_repository at compile time. Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Stefan Beller <sbeller@google.com> Reviewed-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-11Merge branch 'sb/object-store'Junio C Hamano1-0/+1
Refactoring the internal global data structure to make it possible to open multiple repositories, work with and then close them. Rerolled by Duy on top of a separate preliminary clean-up topic. The resulting structure of the topics looked very sensible. * sb/object-store: (27 commits) sha1_file: allow sha1_loose_object_info to handle arbitrary repositories sha1_file: allow map_sha1_file to handle arbitrary repositories sha1_file: allow map_sha1_file_1 to handle arbitrary repositories sha1_file: allow open_sha1_file to handle arbitrary repositories sha1_file: allow stat_sha1_file to handle arbitrary repositories sha1_file: allow sha1_file_name to handle arbitrary repositories sha1_file: add repository argument to sha1_loose_object_info sha1_file: add repository argument to map_sha1_file sha1_file: add repository argument to map_sha1_file_1 sha1_file: add repository argument to open_sha1_file sha1_file: add repository argument to stat_sha1_file sha1_file: add repository argument to sha1_file_name sha1_file: allow prepare_alt_odb to handle arbitrary repositories sha1_file: allow link_alt_odb_entries to handle arbitrary repositories sha1_file: add repository argument to prepare_alt_odb sha1_file: add repository argument to link_alt_odb_entries sha1_file: add repository argument to read_info_alternates sha1_file: add repository argument to link_alt_odb_entry sha1_file: add raw_object_store argument to alt_odb_usable pack: move approximate object count to object store ...
2018-03-26object-store: move packed_git and packed_git_mru to object storeStefan Beller1-0/+1
In a process with multiple repositories open, packfile accessors should be associated to a single repository and not shared globally. Move packed_git and packed_git_mru into the_repository and adjust callers to reflect this. [nd: while at there, wrap access to these two fields in get_packed_git() and get_packed_git_mru(). This allows us to lazily initialize these fields without caller doing that explicitly] Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-03-14sha1_file: convert check_sha1_signature to struct object_idbrian m. carlson1-2/+2
Convert this function to take a pointer to struct object_id and rename it check_object_signature. Introduce temporaries to convert the return values of lookup_replace_object and lookup_replace_object_extended into struct object_id. The temporaries are needed because in order to convert lookup_replace_object, open_istream needs to be converted, and open_istream needs check_sha1_signature to be converted, causing a loop of dependencies. The temporaries will be removed in a future patch. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-03-06Merge branch 'bw/c-plus-plus'Junio C Hamano1-1/+1
Avoid using identifiers that clash with C++ keywords. Even though it is not a goal to compile Git with C++ compilers, changes like this help use of code analysis tools that targets C++ on our codebase. * bw/c-plus-plus: (37 commits) replace: rename 'new' variables trailer: rename 'template' variables tempfile: rename 'template' variables wrapper: rename 'template' variables environment: rename 'namespace' variables diff: rename 'template' variables environment: rename 'template' variables init-db: rename 'template' variables unpack-trees: rename 'new' variables trailer: rename 'new' variables submodule: rename 'new' variables split-index: rename 'new' variables remote: rename 'new' variables ref-filter: rename 'new' variables read-cache: rename 'new' variables line-log: rename 'new' variables imap-send: rename 'new' variables http: rename 'new' variables entry: rename 'new' variables diffcore-delta: rename 'new' variables ...
2018-02-14object: rename function 'typename' to 'type_name'Brandon Williams1-1/+1
Rename C++ keyword in order to bring the codebase closer to being able to be compiled with a C++ compiler. Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-02-02pack-check: convert various uses of SHA-1 to abstract formsbrian m. carlson1-16/+16
Convert various explicit calls to use SHA-1 functions and constants to references to the_hash_algo. Make several strings more generic with respect to the hash algorithm used. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-23pack: move open_pack_index(), parse_pack_index()Jonathan Tan1-0/+1
alloc_packed_git() in packfile.c is duplicated from sha1_file.c. In a subsequent commit, alloc_packed_git() will be removed from sha1_file.c. Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-08Convert the verify_pack callback to struct object_idbrian m. carlson1-11/+14
Make the verify_pack_callback take a pointer to struct object_id. Change the pack checksum to use GIT_MAX_RAWSZ, even though it is not strictly an object ID. Doing so ensures resilience against future hash size changes, and allows us to remove hard-coded assumptions about how big the buffer needs to be. Also, use a union to convert the pointer from nth_packed_object_sha1 to to a pointer to struct object_id. This behavior is compatible with GCC and clang and explicitly sanctioned by C11. The alternatives are to just perform a cast, which would run afoul of strict aliasing rules, but should just work, and changing the pointer into an instance of struct object_id and copying the value. The latter operation could seriously bloat memory usage on fsck, which already uses a lot of memory on some repositories. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-10Merge branch 'rs/qsort'Junio C Hamano1-1/+1
We call "qsort(array, nelem, sizeof(array[0]), fn)", and most of the time third parameter is redundant. A new QSORT() macro lets us omit it. * rs/qsort: show-branch: use QSORT use QSORT, part 2 coccicheck: use --all-includes by default remove unnecessary check before QSORT use QSORT add QSORT
2016-09-29Merge branch 'jk/verify-packfile-gently'Junio C Hamano1-5/+2
A low-level function verify_packfile() was meant to show errors that were detected without dying itself, but under some conditions it didn't and died instead, which has been fixed. * jk/verify-packfile-gently: verify_packfile: check pack validity before accessing data