Commit Graph

3 Commits (afa4ea56fedc3ca04d3b00a3ef930833e7ad68ea)

Author SHA1 Message Date
Johannes Schindelin 606c192380 odb, packfile: use size_t for streaming object sizes
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>
2026-05-09 11:25:31 +09:00
Elijah Newren 8bff5ca030 treewide: ensure one of the appropriate headers is sourced first
We had several C files ignoring the rule to include one of the
appropriate headers first; fix that.

While at it, the rule in Documentation/CodingGuidelines about which
header to include has also fallen out of sync, so update the wording to
mention other allowed headers.

Unfortunately, C files in reftable/ don't actually follow the previous
or updated rule.  If you follow the #include chain in its C files,
reftable/system.h _tends_ to be first (i.e. record.c first includes
record.h, which first includes basics.h, which first includees
system.h), but not always (e.g. publicbasics.c includes another header
first that does not include system.h).  However, I'm going to punt on
making actual changes to the C files in reftable/ since I do not want to
risk bringing it out-of-sync with any version being used externally.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-23 17:25:28 -08:00
Arthur Chan 6713bfc70c fuzz: reorganise the path for existing oss-fuzz fuzzers
In order to provide a better organisation for oss-fuzz fuzzers and
to avoid top-level clustters in the git repository when more fuzzers
are introduced, move the existing fuzzer-related sources to their
own oss-fuzz/ hierarchy.  Grouping the fuzzers into their own
directory, separate their application on fuzz-testing from the core
functionalities of the git code, prvides better and tidier structure
the oss-fuzz fuzzing library to manage, locate, build and execute
those fuzzers for fuzz-testing purposes in future development.

Signed-off-by: Arthur Chan <arthur.chan@adalogics.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-09-19 09:34:35 -07:00