| Age | Commit message (Collapse) | Author | Files | Lines |
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Handle allocation failures when copying records. While at it, convert
from `xstrdup()` to `reftable_strdup()`. Adapt callsites to check for
error codes.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Handle allocation failures in `parse_names()` by returning `NULL` in
case any allocation fails. While at it, refactor the function to return
the array directly instead of assigning it to an out-pointer.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Handle allocation failures in `reftable_calloc()`.
While at it, remove our use of `st_mult()` that would cause us to die on
an overflow. From the caller's point of view there is not much of a
difference between arguments that are too large to be multiplied and a
request that is too big to handle by the allocator: in both cases the
allocation cannot be fulfilled. And in neither of these cases do we want
the reftable library to die.
While we could use `unsigned_mult_overflows()` to handle the overflow
gracefully, we instead open-code it to further our goal of converting
the reftable codebase to become a standalone library that can be reused
by external projects.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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The reftable library provides the ability to swap out allocators. There
is a gap here though, because we continue to use `xstrdup()` even in the
case where all the other allocators have been swapped out.
Introduce `reftable_strdup()` that uses `reftable_malloc()` to do the
allocation.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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The split between "basics" and "publicbasics" is somewhat arbitrary and
not in line with how we typically structure code in the reftable
library. While we do indeed split up headers into a public and internal
part, we don't do that for the compilation unit itself. Furthermore, the
declarations for "publicbasics.c" are in "reftable-malloc.h", which
isn't in line with our naming schema, either.
Fix these inconsistencies by:
- Merging "publicbasics.c" into "basics.c".
- Renaming "reftable-malloc.h" to "reftable-basics.h" as the public
header.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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The reftable library does not use the same memory allocation functions
as the rest of the Git codebase. Instead, as the reftable library is
supposed to be usable as a standalone library without Git, it provides a
set of pluggable memory allocators.
Compared to `xmalloc()` and friends these allocators are _not_ expected
to die when an allocation fails. This design choice is concious, as a
library should leave it to its caller to handle any kind of error. While
it is very likely that the caller cannot really do much in the case of
an out-of-memory situation anyway, we are not the ones to make that
decision.
Curiously though, we never handle allocation errors even though memory
allocation functions are allowed to fail. And as we do not plug in Git's
memory allocator via `reftable_set_alloc()` either the consequence is
that we'd instead segfault as soon as we run out of memory.
While the easy fix would be to wire up `xmalloc()` and friends, it
would only fix the usage of the reftable library in Git itself. Other
users like libgit2, which is about to revive its efforts to land a
backend for reftables, wouldn't be able to benefit from this solution.
Instead, we are about to do it the hard way: adapt all allocation sites
to perform error checking. Introduce a new error code for out-of-memory
errors that we will wire up in subsequent steps.
This commit also serves as the motivator for all the remaining steps in
this series such that we do not have to repeat the same arguments in
every single subsequent commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Signed-off-by: Junio C Hamano <gitster@pobox.com>
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The checksum at the tail of files are now computed without
collision detection protection. This is safe as the consumer of
the information to protect itself from replay attacks checks for
hash collisions independently.
* tb/weak-sha1-for-tail-sum:
csum-file.c: use unsafe SHA-1 implementation when available
Makefile: allow specifying a SHA-1 for non-cryptographic uses
hash.h: scaffolding for _unsafe hashing variants
sha1: do not redefine `platform_SHA_CTX` and friends
pack-objects: use finalize_object_file() to rename pack/idx/etc
finalize_object_file(): implement collision check
finalize_object_file(): refactor unlink_or_warn() placement
finalize_object_file(): check for name collision before renaming
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Leakfixes.
* 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()
...
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More leak-fixes.
* 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
...
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When "git sparse-checkout disable" turns a sparse checkout into a
regular checkout, the index is fully expanded. This totally
expected behaviour however had an "oops, we are expanding the
index" advice message, which has been corrected.
* ds/sparse-checkout-expansion-advice:
sparse-checkout: disable advice in 'disable'
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In load_cache_entries_threaded(), each thread allocates its own memory
pool. This pool needs to be cleaned up while closing the threads down,
or it will be leaked.
This ce_mem_pool pointer could theoretically be converted to an inline
copy of the struct, but the use of a pointer helps with existing lazy-
initialization logic. Adjusting that behavior only to avoid this pointer
would be a much bigger change.
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Signed-off-by: Junio C Hamano <gitster@pobox.com>
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"git --git-dir=nowhere cmd" failed to properly notice that it
wasn't in any repository while processing includeIf.onbranch
configuration and instead crashed.
* ps/includeif-onbranch-cornercase-fix:
config: fix evaluating "onbranch" with nonexistent git dir
t1305: exercise edge cases of "onbranch" includes
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Background tasks "git maintenance" runs may need to use credential
information when going over the network, but a credential helper
may work only in an interactive environment, and end up blocking a
scheduled task waiting for UI. Credential helpers can now behave
differently when they are not running interactively.
* ds/background-maintenance-with-credential:
scalar: configure maintenance during 'reconfigure'
maintenance: add custom config to background jobs
credential: add new interactive config option
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"git archive" with pathspec magic that uses the attribute
information did not work well, which has been corrected.
* rs/archive-with-attr-pathspec-fix:
archive: load index before pathspec checks
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Code clean-up.
* rs/commit-graph-ununleak:
commit-graph: remove unnecessary UNLEAK
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When a subprocess to work in a submodule spawned by "git submodule"
fails with SIGPIPE, the parent Git process caught the death of it,
but gave a generic "failed to work in that submodule", which was
misleading. We now behave as if the parent got SIGPIPE and die.
* pw/submodule-process-sigpipe:
submodule status: propagate SIGPIPE
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Give timeout to the locking code to write to reftable.
* ps/reftable-concurrent-writes:
refs/reftable: reload locked stack when preparing transaction
reftable/stack: allow locking of outdated stacks
refs/reftable: introduce "reftable.lockTimeout"
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The list of push options is leaking. Plug the leak.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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* 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()
...
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* 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
...
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Also fix issue reported by Anders Jonsson
<anders.jonsson@norsjovallen.se>.
Signed-off-by: Peter Krefting <peter@softwolves.pp.se>
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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>
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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>
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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>
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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>
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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>
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