Commit Graph

75205 Commits

Author SHA1 Message Date
Patrick Steinhardt
a6c30623d7 remote: fix leaking push reports
The push reports that report failures to the user when pushing a
reference leak in several places. Plug these leaks by introducing a new
function `ref_push_report_free()` that frees the list of reports and
call it as required. While at it, fix a trivially leaking error string
in the vicinity.

These leaks get hit in t5411, but plugging them does not make the whole
test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:08 -07:00
Patrick Steinhardt
12f0fb9538 t/helper: fix leaks in proc-receive helper
Fix trivial leaks in the proc-receive helpe.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:08 -07:00
Patrick Steinhardt
2f0ee051dd pack-write: fix return parameter of write_rev_file_order()
While the return parameter of `write_rev_file_order()` is a string
constant, the function may indeed return an allocated string when its
first parameter is a `NULL` pointer. This makes for a confusing calling
convention, where callers need to be aware of these intricate ownership
rules and cast away the constness to free the string in some cases.

Adapt the function and its caller `write_rev_file()` to always return an
allocated string and adapt callers to always free the return value.

Note that this requires us to also adapt `rename_tmp_packfile()`, which
compares the pointers to packfile data with each other. Now that the
path of the reverse index file gets allocated unconditionally the check
will always fail. This is fixed by using strcmp(3P) instead, which also
feels way less fragile.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:08 -07:00
Patrick Steinhardt
6512d6e473 revision: fix leaking saved parents
The `saved_parents` slab is used by `--full-diff` to save parents of a
commit which we are about to rewrite. We do not release its contents
once it's not used anymore, causing a memory leak. Plug it.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:07 -07:00
Patrick Steinhardt
4cc2cee5ac revision: fix memory leaks when rewriting parents
Both `rewrite_parents()` and `remove_duplicate_parents()` may end up
dropping some parents from a commit without freeing the respective
`struct commit_list` items. This causes a bunch of memory leaks. Plug
these.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:07 -07:00
Patrick Steinhardt
9d4855eef3 midx-write: fix leaking buffer
The buffer used to compute the final MIDX name is never released. Plug
this memory leak.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:07 -07:00
Patrick Steinhardt
7f97266ee1 pack-bitmap-write: fix leaking OID array
Fix a leaking OID array in `write_pseudo_merges()`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:07 -07:00
Patrick Steinhardt
d0ab6630a7 pseudo-merge: fix leaking strmap keys
When creating a new pseudo-merge group we collect a set of matchnig
commits and put them into a string map. This strmap is initialized such
that it does not allocate its keys, and instead we try to pass ownership
of the keys to it via `strmap_put()`. This isn't how it works though:
the strmap will never try to release these keys, and consequently they
end up leaking.

Fix this leak by initializing the strmap as duplicating its keys and not
trying to hand over ownership.

The leak is exposed by t5333, but plugging it does not yet make the full
test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:06 -07:00
Patrick Steinhardt
55e563a90c pseudo-merge: fix various memory leaks
Fix various memory leaks hit by the pseudo-merge machinery. These leaks
are exposed by t5333, but plugging them does not yet make the whole test
suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:06 -07:00
Patrick Steinhardt
5ce08ed4fb line-log: fix several memory leaks
As described in "line-log.c" itself, the code is "leaking like a sieve".
These leaks are all of rather trivial nature, so this commit plugs them
without going too much into details for each of those leaks.

The leaks are hit by t4211, but plugging them alone does not make the
full test suite pass. The remaining leaks are unrelated to the line-log
subsystem.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:06 -07:00
Patrick Steinhardt
a5aecb2cdc diff: improve lifecycle management of diff queues
The lifecycle management of diff queues is somewhat confusing:

  - For most of the part this can be attributed to `DIFF_QUEUE_CLEAR()`,
    which does not release any memory but rather initializes the queue,
    only. This is in contrast to our common naming schema, where
    "clearing" means that we release underlying memory and then
    re-initialize the data structure such that it is ready to use.

  - A second offender is `diff_free_queue()`, which does not free the
    queue structure itself. It is rather a release-style function.

Refactor the code to make things less confusing. `DIFF_QUEUE_CLEAR()` is
replaced by `DIFF_QUEUE_INIT` and `diff_queue_init()`, while
`diff_free_queue()` is replaced by `diff_queue_release()`. While on it,
adapt callsites where we call `DIFF_QUEUE_CLEAR()` with the intent to
release underlying memory to instead call `diff_queue_clear()` to fix
memory leaks.

This memory leak is exposed by t4211, but plugging it alone does not
make the whole test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:05 -07:00
Patrick Steinhardt
fdf972a9df builtin/revert: fix leaking gpg_sign and strategy config
We leak the config values when `gpg_sign` or `strategy` options are
being overridden via the command line. To fix this we need to free the
old value, which requires us to figure out whether the value was changed
via an option in the first place. The easy way to do this, which is to
initialize local variables with `NULL`, doesn't work because we cannot
tell the case where the user has passed e.g. `--no-gpg-sign`. Instead,
we use a sentinel value for both values that we can compare against to
check whether the user has passed the option.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:05 -07:00
Patrick Steinhardt
58888c0401 t/helper: fix leaking repository in partial-clone helper
We initialize but never clear a repository in the partial-clone test
helper. Plug this leak.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:05 -07:00
Patrick Steinhardt
6361dea6e8 builtin/clone: fix leaking repo state when cloning with bundle URIs
When cloning with bundle URIs we re-initialize `the_repository` after
having fetched the bundle. This causes a bunch of memory leaks though
because we do not release its previous state.

These leaks can be plugged by calling `repo_clear()` before we call
`repo_init()`. But this causes another issue because the remote that we
used is tied to the lifetime of the repository's remote state, which
would also get released. We thus have to make sure that it does not get
free'd under our feet.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:04 -07:00
Patrick Steinhardt
a0f2a2f581 builtin/pack-redundant: fix various memory leaks
There are various different memory leaks in git-pack-redundant(1),
mostly caused by not even trying to free allocated memory. Fix them.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:04 -07:00
Patrick Steinhardt
64fe1e4a8c builtin/stash: fix leaking pathspec_from_file
The `OPT_PATHSPEC_FROM_FILE()` option maps to `OPT_FILENAME()`, which we
know will always allocate memory when passed. We never free the memory
though, causing a memory leak. Plug it.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:04 -07:00
Patrick Steinhardt
5cca114973 submodule: fix leaking submodule entry list
The submodule entry list returned by `submodules_of_tree()` is never
completely free'd by its only caller. Introduce a new function that
free's the list for us and call it.

While at it, also fix the leaking `branch_point` string.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:03 -07:00
Patrick Steinhardt
666643fa89 wt-status: fix leaking buffer with sparse directories
When hitting a sparse directory in `wt_status_collect_changes_initial()`
we use a `struct strbuf` to assemble the directory's name. We never free
that buffer though, causing a memory leak.

Fix the leak by releasing the buffer. While at it, move the buffer
outside of the loop and reset it to save on some wasteful allocations.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:03 -07:00
Patrick Steinhardt
c75841687b shell: fix leaking strings
There are two memory leaks in "shell.c". The first one in `run_shell()`
is trivial and fixed without further explanation. The second one in
`cmd_main()` happens because we overwrite the `prog` variable, which
contains an allocated string. In fact though, the memory pointed to by
that variable is still in use because we use `split_cmdline()`, which
may create pointers into the middle of that string. But as we do not
have a direct pointer to the head of the allocated string anymore, we
get a complaint by the leak checker.

Address this by not overwriting the `prog` pointer.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:03 -07:00
Patrick Steinhardt
d607bd8816 scalar: fix leaking repositories
In the scalar code we iterate through multiple repositories,
initializing each of them. We never clear them though, causing memory
leaks. Plug them.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:02 -07:00
Patrick Steinhardt
a69d120c07 read-cache: fix leaking hash context in do_write_index()
When writing an index with the EOIE extension we allocate a separate
hash context. We never free that context though, causing a memory leak.
Plug it.

This leak is exposed by t9210, but plugging it alone does not make the
whole test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:02 -07:00
Patrick Steinhardt
9a48fc1da2 builtin/annotate: fix leaking args vector
We're leaking the args vector in git-annotate(1) because we never clear
it. Fixing it isn't as easy as calling `strvec_clear()` though because
calling `cmd_blame()` will cause the underlying array to be modified.
Instead, we also need to pass a shallow copy of the argv array to the
function.

Do so to plug the memory leaks.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30 11:23:02 -07:00
Junio C Hamano
a5031223cd Merge branch 'jk/http-leakfixes' into ps/leakfixes-part-8
* jk/http-leakfixes: (28 commits)
  http-push: clean up local_refs at exit
  http-push: clean up loose request when falling back to packed
  http-push: clean up objects list
  http-push: free xml_ctx.cdata after use
  http-push: free remote_ls_ctx.dentry_name
  http-push: free transfer_request strbuf
  http-push: free transfer_request dest field
  http-push: free curl header lists
  http-push: free repo->url string
  http-push: clear refspecs before exiting
  http-walker: free fake packed_git list
  remote-curl: free HEAD ref with free_one_ref()
  http: stop leaking buffer in http_get_info_packs()
  http: call git_inflate_end() when releasing http_object_request
  http: fix leak of http_object_request struct
  http: fix leak when redacting cookies from curl trace
  transport-helper: fix leak of dummy refs_list
  fetch-pack: clear pack lockfiles list
  fetch: free "raw" string when shrinking refspec
  transport-helper: fix strbuf leak in push_refs_with_push()
  ...
2024-09-30 11:22:21 -07:00
Junio C Hamano
674e46fdd5 Merge branch 'ps/leakfixes-part-7' into ps/leakfixes-part-8
* ps/leakfixes-part-7: (23 commits)
  diffcore-break: fix leaking filespecs when merging broken pairs
  revision: fix leaking parents when simplifying commits
  builtin/maintenance: fix leak in `get_schedule_cmd()`
  builtin/maintenance: fix leaking config string
  promisor-remote: fix leaking partial clone filter
  grep: fix leaking grep pattern
  submodule: fix leaking submodule ODB paths
  trace2: destroy context stored in thread-local storage
  builtin/difftool: plug several trivial memory leaks
  builtin/repack: fix leaking configuration
  diffcore-order: fix leaking buffer when parsing orderfiles
  parse-options: free previous value of `OPTION_FILENAME`
  diff: fix leaking orderfile option
  builtin/pull: fix leaking "ff" option
  dir: fix off by one errors for ignored and untracked entries
  builtin/submodule--helper: fix leaking remote ref on errors
  t/helper: fix leaking subrepo in nested submodule config helper
  builtin/submodule--helper: fix leaking error buffer
  builtin/submodule--helper: clear child process when not running it
  submodule: fix leaking update strategy
  ...
2024-09-30 11:22:10 -07:00
Peter Krefting
4de34a4233 l10n: sv.po: Update Swedish translation
Also fix issue reported by Anders Jonsson
<anders.jonsson@norsjovallen.se>.

Signed-off-by: Peter Krefting <peter@softwolves.pp.se>
2024-09-28 15:45:19 +01:00
Taylor Blau
1b9e9be8b4 csum-file.c: use unsafe SHA-1 implementation when available
Update hashwrite() and friends to use the unsafe_-variants of hashing
functions, calling for e.g., "the_hash_algo->unsafe_update_fn()" instead
of "the_hash_algo->update_fn()".

These callers only use the_hash_algo to produce a checksum, which we
depend on for data integrity, but not for cryptographic purposes, so
these callers are safe to use the unsafe (non-collision detecting) SHA-1
implementation.

To time this, I took a freshly packed copy of linux.git, and ran the
following with and without the OPENSSL_SHA1_UNSAFE=1 build-knob. Both
versions were compiled with -O3:

    $ git for-each-ref --format='%(objectname)' refs/heads refs/tags >in
    $ valgrind --tool=callgrind ~/src/git/git-pack-objects \
        --revs --stdout --all-progress --use-bitmap-index <in >/dev/null

Without OPENSSL_SHA1_UNSAFE=1 (that is, using the collision-detecting
SHA-1 implementation for both cryptographic and non-cryptographic
purposes), we spend a significant amount of our instruction count in
hashwrite():

    $ callgrind_annotate --inclusive=yes | grep hashwrite | head -n1
    159,998,868,413 (79.42%)  /home/ttaylorr/src/git/csum-file.c:hashwrite [/home/ttaylorr/src/git/git-pack-objects]

, and the resulting "clone" takes 19.219 seconds of wall clock time,
18.94 seconds of user time and 0.28 seconds of system time.

Compiling with OPENSSL_SHA1_UNSAFE=1, we spend ~60% fewer instructions
in hashwrite():

    $ callgrind_annotate --inclusive=yes | grep hashwrite | head -n1
     59,164,001,176 (58.79%)  /home/ttaylorr/src/git/csum-file.c:hashwrite [/home/ttaylorr/src/git/git-pack-objects]

, and generate the resulting "clone" much faster, in only 11.597 seconds
of wall time, 11.37 seconds of user time, and 0.23 seconds of system
time, for a ~40% speed-up.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 11:27:47 -07:00
Taylor Blau
06c92dafb8 Makefile: allow specifying a SHA-1 for non-cryptographic uses
Introduce _UNSAFE variants of the OPENSSL_SHA1, BLK_SHA1, and
APPLE_COMMON_CRYPTO_SHA1 compile-time knobs which indicate which SHA-1
implementation is to be used for non-cryptographic uses.

There are a couple of small implementation notes worth mentioning:

  - There is no way to select the collision detecting SHA-1 as the
    "fast" fallback, since the fast fallback is only for
    non-cryptographic uses, and is meant to be faster than our
    collision-detecting implementation.

  - There are no similar knobs for SHA-256, since no collision attacks
    are presently known and thus no collision-detecting implementations
    actually exist.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 11:27:47 -07:00
Taylor Blau
253ed9ecff hash.h: scaffolding for _unsafe hashing variants
Git's default SHA-1 implementation is collision-detecting, which hardens
us against known SHA-1 attacks against Git objects. This makes Git
object writes safer at the expense of some speed when hashing through
the collision-detecting implementation, which is slower than
non-collision detecting alternatives.

Prepare for loading a separate "unsafe" SHA-1 implementation that can be
used for non-cryptographic purposes, like computing the checksum of
files that use the hashwrite() API.

This commit does not actually introduce any new compile-time knobs to
control which implementation is used as the unsafe SHA-1 variant, but
does add scaffolding so that the "git_hash_algo" structure has five new
function pointers which are "unsafe" variants of the five existing
hashing-related function pointers:

  - git_hash_init_fn unsafe_init_fn
  - git_hash_clone_fn unsafe_clone_fn
  - git_hash_update_fn unsafe_update_fn
  - git_hash_final_fn unsafe_final_fn
  - git_hash_final_oid_fn unsafe_final_oid_fn

The following commit will introduce compile-time knobs to specify which
SHA-1 implementation is used for non-cryptographic uses.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 11:27:47 -07:00
Taylor Blau
4c61a1d040 sha1: do not redefine platform_SHA_CTX and friends
Our in-tree SHA-1 wrappers all define platform_SHA_CTX and related
macros to point at the opaque "context" type, init, update, and similar
functions for each specific implementation.

In hash.h, we use these platform_ variables to set up the function
pointers for, e.g., the_hash_algo->init_fn(), etc.

But while these header files have a header-specific macro that prevents
them declaring their structs / functions multiple times, they
unconditionally define the platform variables, making it impossible to
load multiple SHA-1 implementations at once.

As a prerequisite for loading a separate SHA-1 implementation for
non-cryptographic uses, only define the platform_ variables if they have
not already been defined.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 11:27:47 -07:00
Taylor Blau
c177d3dc50 pack-objects: use finalize_object_file() to rename pack/idx/etc
In most places that write files to the object database (even packfiles
via index-pack or fast-import), we use finalize_object_file(). This
prefers link()/unlink() over rename(), because it means we will prefer
data that is already in the repository to data that we are newly
writing.

We should do the same thing in pack-objects. Even though we don't think
of it as accepting outside data (and thus not being susceptible to
collision attacks), in theory a determined attacker could present just
the right set of objects to cause an incremental repack to generate
a pack with their desired hash.

This has some test and real-world fallout, as seen in the adjustment to
t5303 below. That test script assumes that we can "fix" corruption by
repacking into a good state, including when the pack generated by that
repack operation collides with a (corrupted) pack with the same hash.
This violates our assumption from the previous adjustments to
finalize_object_file() that if we're moving a new file over an existing
one, that since their checksums match, so too must their contents.

This makes "fixing" corruption like this a more explicit operation,
since the test (and users, who may fix real-life corruption using a
similar technique) must first move the broken contents out of the way.

Note also that we now call adjust_shared_perm() twice. We already call
adjust_shared_perm() in stage_tmp_packfiles(), and now call it again in
finalize_object_file(). This is somewhat wasteful, but cleaning up the
existing calls to adjust_shared_perm() is tricky (because sometimes
we're writing to a tmpfile, and sometimes we're writing directly into
the final destination), so let's tolerate some minor waste until we can
more carefully clean up the now-redundant calls.

Co-authored-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>
2024-09-27 11:27:47 -07:00
Taylor Blau
b1b8dfde69 finalize_object_file(): implement collision check
We've had "FIXME!!! Collision check here ?" in finalize_object_file()
since aac1794132 (Improve sha1 object file writing., 2005-05-03). That
is, when we try to write a file with the same name, we assume the
on-disk contents are the same and blindly throw away the new copy.

One of the reasons we never implemented this is because the files it
moves are all named after the cryptographic hash of their contents
(either loose objects, or packs which have their hash in the name these
days). So we are unlikely to see such a collision by accident. And even
though there are weaknesses in sha1, we assume they are mitigated by our
use of sha1dc.

So while it's a theoretical concern now, it hasn't been a priority.
However, if we start using weaker hashes for pack checksums and names,
this will become a practical concern. So in preparation, let's actually
implement a byte-for-byte collision check.

The new check will cause the write of new differing content to be a
failure, rather than a silent noop, and we'll retain the temporary file
on disk. If there's no collision present, we'll clean up the temporary
file as usual after either rename()-ing or link()-ing it into place.

Note that this may cause some extra computation when the files are in
fact identical, but this should happen rarely.

Loose objects are exempt from this check, and the collision check may be
skipped by calling the _flags variant of this function with the
FOF_SKIP_COLLISION_CHECK bit set. This is done for a couple of reasons:

  - We don't treat the hash of the loose object file's contents as a
    checksum, since the same loose object can be stored using different
    bytes on disk (e.g., when adjusting core.compression, using a
    different version of zlib, etc.).

    This is fundamentally different from cases where
    finalize_object_file() is operating over a file which uses the hash
    value as a checksum of the contents. In other words, a pair of
    identical loose objects can be stored using different bytes on disk,
    and that should not be treated as a collision.

  - We already use the path of the loose object as its hash value /
    object name, so checking for collisions at the content level doesn't
    add anything.

    Adding a content-level collision check would have to happen at a
    higher level than in finalize_object_file(), since (avoiding race
    conditions) writing an object loose which already exists in the
    repository will prevent us from even reaching finalize_object_file()
    via the object freshening code.

    There is a collision check in index-pack via its `check_collision()`
    function, but there isn't an analogous function in unpack-objects,
    which just feeds the result to write_object_file().

    So skipping the collision check here does not change for better or
    worse the hardness of loose object writes.

As a small note related to the latter bullet point above, we must teach
the tmp-objdir routines to similarly skip the content-level collision
checks when calling migrate_one() on a loose object file, which we do by
setting the FOF_SKIP_COLLISION_CHECK bit when we are inside of a loose
object shard.

Co-authored-by: Jeff King <peff@peff.net>
Signed-off-by: Jeff King <peff@peff.net>
Helped-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 11:27:47 -07:00
Taylor Blau
9ca7c2c13b finalize_object_file(): refactor unlink_or_warn() placement
As soon as we've tried to link() a temporary object into place, we then
unlink() the tempfile immediately, whether we were successful or not.

For the success case, this is because we no longer need the old file
(it's now linked into place).

For the error case, there are two outcomes. Either we got EEXIST, in
which case we consider the collision to be a noop. Or we got a system
error, in which we case we are just cleaning up after ourselves.

Using a single line for all of these cases has some problems:

  - in the error case, our unlink() may clobber errno, which we use in
    the error message

  - for the collision case, there's a FIXME that indicates we should do
    a collision check. In preparation for implementing that, we'll need
    to actually hold on to the file.

Split these three cases into their own calls to unlink_or_warn(). This
is more verbose, but lets us do the right thing in each case.

Co-authored-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>
2024-09-27 11:27:46 -07:00
Taylor Blau
d1b44bb764 finalize_object_file(): check for name collision before renaming
We prefer link()/unlink() to rename() for object files, with the idea
that we should prefer the data that is already on disk to what is
incoming. But we may fall back to rename() if the user has configured us
to do so, or if the filesystem seems not to support cross-directory
links. This loses the "prefer what is on disk" property.

We can mitigate this somewhat by trying to stat() the destination
filename before doing the rename. This is racy, since the object could
be created between the stat() and rename() calls. But in practice it is
expanding the definition of "what is already on disk" to be the point
that the function is called. That is enough to deal with any potential
attacks where an attacker is trying to collide hashes with what's
already in the repository.

Co-authored-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>
2024-09-27 11:27:46 -07:00
Patrick Steinhardt
12dfc2475c diffcore-break: fix leaking filespecs when merging broken pairs
When merging file pairs after they have been broken up we queue a new
file pair and discard the broken-up ones. The newly-queued file pair
reuses one filespec of the broken up pairs each, where the respective
other filespec gets discarded. But we only end up freeing the filespec's
data, not the filespec itself, and thus leak memory.

Fix these leaks by using `free_filespec()` instead.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:37 -07:00
Patrick Steinhardt
fa016423c7 revision: fix leaking parents when simplifying commits
When simplifying commits, e.g. because they are treesame with their
parents, we unset the commit's parent pointers but never free them. Plug
the resulting memory leaks.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:37 -07:00
Patrick Steinhardt
b6c3f8e12c builtin/maintenance: fix leak in get_schedule_cmd()
The `get_schedule_cmd()` function allows us to override the schedule
command with a specific test command such that we can verify the
underlying logic in a platform-independent way. Its memory management is
somewhat wild though, because it basically gives up and assigns an
allocated string to the string constant output pointer. While this part
is marked with `UNLEAK()` to mask this, we also leak the local string
lists.

Rework the function such that it has a separate out parameter. If set,
we will assign it the final allocated command. Plug the other memory
leaks and create a common exit path.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:37 -07:00
Patrick Steinhardt
84e9fc361d builtin/maintenance: fix leaking config string
When parsing the maintenance strategy from config we allocate a config
string, but do not free it after parsing it. Plug this leak by instead
using `git_config_get_string_tmp()`, which does not allocate any memory.

This leak is exposed by t7900, but plugging it alone does not make the
test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:37 -07:00
Patrick Steinhardt
355b3190ee promisor-remote: fix leaking partial clone filter
The partial clone filter of a promisor remote is never free'd, causing
memory leaks. Furthermore, in case multiple partial clone filters are
defined for the same remote, we'd overwrite previous values without
freeing them.

Fix these leaks.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:36 -07:00
Patrick Steinhardt
6d82437a47 grep: fix leaking grep pattern
When creating a pattern via `create_grep_pat()` we allocate the pattern
member of the structure regardless of the token type. But later, when we
try to free the structure, we free the pattern member conditionally on
the token type and thus leak memory.

Plug this leak. The leak is exposed by t7814, but plugging it alone does
not make the whole test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:36 -07:00
Patrick Steinhardt
f8d2ca7246 submodule: fix leaking submodule ODB paths
In `add_submodule_odb_by_path()` we add a path into a global string
list. The list is initialized with `NODUP`, which means that we do not
pass ownership of strings to the list. But we use `xstrdup()` when we
insert a path, with the consequence that the string will never get
free'd.

Plug the leak by marking the list as `DUP`. There is only a single
callsite where we insert paths anyway, and as explained above that
callsite was mishandling the allocation.

This leak is exposed by t7814, but plugging it does not make the whole
test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:36 -07:00
Patrick Steinhardt
64d9adafba trace2: destroy context stored in thread-local storage
Each thread may have a specific context in the trace2 subsystem that we
set up via thread-local storage. We do not set up a destructor for this
data though, which means that the context data will leak.

Plug this leak by installing a destructor. This leak is exposed by
t7814, but plugging it alone does not make the whole test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:36 -07:00
Patrick Steinhardt
7f795a1715 builtin/difftool: plug several trivial memory leaks
There are several leaking data structures in git-difftool(1). Plug them.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:36 -07:00
Patrick Steinhardt
dea4a9521e builtin/repack: fix leaking configuration
When repacking, we assemble git-pack-objects(1) arguments both for the
"normal" pack and for the cruft pack. This configuration gets populated
with a bunch of `OPT_PASSTHRU` options that we end up passing to the
child process. These options are allocated, but never free'd.

Create a new `pack_objects_args_release()` function that releases the
memory for us and call it for both sets of options.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:36 -07:00
Patrick Steinhardt
6932ec8183 diffcore-order: fix leaking buffer when parsing orderfiles
In `prepare_order()` we parse an orderfile and assign it to a global
array. In order to save on some allocations, we replace newlines with
NUL characters and then assign pointers into the allocated buffer to
that array. This can cause the buffer to be completely unreferenced
though in some cases, e.g. because the order file is empty or because we
had to use `xmemdupz()` to copy the lines instead of NUL-terminating
them.

Refactor the code to always `xmemdupz()` the strings. This is a bit
simpler, and it is rather unlikely that saving a handful of allocations
really matters. This allows us to release the string buffer and thus
plug the memory leak.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:35 -07:00
Patrick Steinhardt
cf8c4237eb parse-options: free previous value of OPTION_FILENAME
The `OPTION_FILENAME` option always assigns either an allocated string
or `NULL` to the value. In case it is passed multiple times it does not
know to free the previous value though, which causes a memory leak.

Refactor the function to always free the previous value. None of the
sites where this option is used pass a string constant, so this change
is safe.

While at it, fix the argument of `fix_filename()` to be a string
constant. The only reason why it's not is because we use it as an
in-out-parameter, where the input is a constant and the output is not.
This is weird and unnecessary, as we can just return the result instead
of using the parameter for this.

This leak is being hit in t7621, but plugging it alone does not make the
test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:35 -07:00
Patrick Steinhardt
76c7e708bb diff: fix leaking orderfile option
The `orderfile` diff option is being assigned via `OPT_FILENAME()`,
which assigns an allocated string to the variable. We never free it
though, causing a memory leak.

Change the type of the string to `char *` and free it to plug the leak.
This also requires us to use `xstrdup()` to assign the global config to
it in case it is set.

This leak is being hit in t7621, but plugging it alone does not make the
test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:35 -07:00
Patrick Steinhardt
49af1b7722 builtin/pull: fix leaking "ff" option
The `opt_ff` field gets populated either via `OPT_PASSTHRU` via
`config_get_ff()` or when `--rebase` is passed. So we sometimes end up
overriding the value in `opt_ff` with another value, but we do not free
the old value, causing a memory leak.

Adapt the type of the variable to be `char *` and consistently assign
allocated strings to it such that we can easily free it when it is being
overridden.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:35 -07:00
Patrick Steinhardt
04ff8008f3 dir: fix off by one errors for ignored and untracked entries
In `treat_directory()` we perform some logic to handle ignored and
untracked entries. When populating a directory with entries we first
save the current number of ignored/untracked entries and then populate
new entries at the end of our arrays that keep track of those entries.
When we figure out that all entries have been ignored/are untracked we
then remove this tail of entries from those vectors again. But there is
an off by one error in both paths that causes us to not free the first
ignored and untracked entries, respectively.

Fix these off-by-one errors to plug the resulting leak. While at it,
massage the code a bit to match our modern code style.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:35 -07:00
Patrick Steinhardt
5bf922a4e9 builtin/submodule--helper: fix leaking remote ref on errors
When `update_submodule()` fails we return with `die_message()`, which
only causes us to print the same message as `die()` would without
actually causing the process to die. We don't free memory in that case
and thus leak memory.

Fix the leak by freeing the remote ref.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:35 -07:00
Patrick Steinhardt
f1652c04b5 t/helper: fix leaking subrepo in nested submodule config helper
In the "submodule-nested-repo-config" helper we create a submodule
repository and print its configuration. We do not clear the repo,
causing a memory leak. Plug it.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-27 08:25:35 -07:00