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2026-03-25hook: show disabled hooks in "git hook list"Adrian Ratiu
Disabled hooks were filtered out of the cache entirely, making them invisible to "git hook list". Keep them in the cache with a new "disabled" flag which is propagated to the respective struct hook. "git hook list" now shows disabled hooks as tab-separated columns, with the status as a prefix before the name (like scope with --show-scope). With --show-scope it looks like: $ git hook list --show-scope pre-commit global linter local disabled no-leaks hook from hookdir A disabled hook without a command issues a warning instead of the fatal "hook.X.command must be configured" error. We could also throw an error, however it seemd a bit excessive to me in this case. Suggested-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-03-25hook: show config scope in git hook listAdrian Ratiu
Users running "git hook list" can see which hooks are configured but have no way to tell at which config scope (local, global, system...) each hook was defined. Store the scope from ctx->kvi->scope in the single-pass config callback, then carry it through the cache to the hook structs, so we can expose it to users via the "git hook list --show-scope" flag, which mirrors the existing git config --show-scope convention. Without the flag the output is unchanged. The scope is printed as a tab-separated prefix (like "git config --show-scope"), making it unambiguously machine-parseable even when the friendly name contains spaces. Example usage: $ git hook list --show-scope pre-commit global linter local no-leaks hook from hookdir Traditional hooks from the hookdir are unaffected by --show-scope since the config scope concept does not apply to them. Suggested-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-03-25hook: introduce hook_config_cache_entry for per-hook dataAdrian Ratiu
Replace the bare `char *command` util pointer stored in each string_list item with a heap-allocated `struct hook_config_cache_entry` that carries that command string. This is just a refactoring with no behavior changes, to give the cache entry room to grow, so it can carry the additional hook metadata we'll be adding in the following commits. Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-03-25hook: make consistent use of friendly-name in docsAdrian Ratiu
Both `name` and `friendly-name` is being used. Standardize on `friendly-name` for consistency since name is rather generic, even when used in the hooks namespace. Suggested-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-03-25hook: replace hook_list_clear() -> string_list_clear_func()Adrian Ratiu
Replace the custom function with string_list_clear_func() which is a more common pattern for clearing a string_list. To be able to do this, rework hook_clear() into hook_free(), so it can be passed to string_list_clear_func(). A slight complication is the need to keep a copy of the internal cb data free() pointer, however I think it's worth it since the API becomes cleaner, e.g. no more calls with NULL function args like hook_list_clear(hooks, NULL). In other words, the callers don't need to keep track of hook internal state to determine when cleanup is necessary or not (pass NULL) because each `struct hook` now owns its data_free callback. Suggested-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-03-25hook: detect & emit two more bugsAdrian Ratiu
Trigger a bug when an unknown hook type is encountered while setting up hook execution. Also issue a bug if a configured hook is enabled without a cmd. Mostly useful for defensive coding. Suggested-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-03-25hook: rename cb_data_free/alloc -> hook_data_free/allocAdrian Ratiu
Rename the hook callback function types to use the hook prefix. This is a style fix with no logic changes. Suggested-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-03-25hook: fix minor style issuesAdrian Ratiu
Fix some minor style nits pointed out by Patrick, Junio and Eric: * Use CALLOC_ARRAY instead of xcalloc. * Init struct members during declaration. * Simplify if condition boolean logic. * Missing curly braces in if/else stmts. * Unnecessary header includes. * Capitalization and full-stop in error/warn messages. * Curly brace on separate line when defining struct. * Comment spelling: free'd -> freed. * Sort the included headers. * Blank line fixes to improve readability. These contain no logic changes, the code behaves the same as before. Suggested-by: Eric Sunshine <sunshine@sunshineco.com> Suggested-by: Junio C Hamano <gitster@pobox.com> Suggested-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-03-25hook: move unsorted_string_list_remove() to string-list.[ch]Adrian Ratiu
Move the convenience wrapper from hook to string-list since it's a more suitable place. Add a doc comment to the header. Also add a free_util arg to make the function more generic and make the API similar to other functions in string-list.h. Update the existing call-sites. Suggested-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-02-19hook: allow out-of-repo 'git hook' invocationsEmily Shaffer
Since hooks can now be supplied via the config, and a config can be present without a gitdir via the global and system configs, we can start to allow 'git hook run' to occur without a gitdir. This enables us to do things like run sendemail-validate hooks when running 'git send-email' from a nongit directory. It still doesn't make sense to look for hooks in the hookdir in nongit repos, though, as there is no hookdir. Signed-off-by: Emily Shaffer <emilyshaffer@google.com> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-02-19hook: allow event = "" to overwrite previous valuesAdrian Ratiu
Add the ability for empty events to clear previously set multivalue variables, so the newly added "hook.*.event" behave like the other multivalued keys. Suggested-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-02-19hook: allow disabling config hooksAdrian Ratiu
Hooks specified via configs are always enabled, however users might want to disable them without removing from the config, like locally disabling a global hook. Add a hook.<name>.enabled config which defaults to true and can be optionally set for each configured hook. Suggested-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-02-19hook: include hooks from the configAdrian Ratiu
Teach the hook.[hc] library to parse configs to populate the list of hooks to run for a given event. Multiple commands can be specified for a given hook by providing "hook.<friendly-name>.command = <path-to-hook>" and "hook.<friendly-name>.event = <hook-event>" lines. Hooks will be started in config order of the "hook.<name>.event" lines and will be run sequentially (.jobs == 1) like before. Running the hooks in parallel will be enabled in a future patch. The "traditional" hook from the hookdir is run last, if present. A strmap cache is added to struct repository to avoid re-reading the configs on each rook run. This is useful for hooks like the ref-transaction which gets executed multiple times per process. Examples: $ git config --get-regexp "^hook\." hook.bar.command=~/bar.sh hook.bar.event=pre-commit # Will run ~/bar.sh, then .git/hooks/pre-commit $ git hook run pre-commit Signed-off-by: Emily Shaffer <emilyshaffer@google.com> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-02-19hook: add "git hook list" commandEmily Shaffer
The previous commit introduced an ability to run multiple commands for hook events and next commit will introduce the ability to define hooks from configs, in addition to the "traditional" hooks from the hookdir. Introduce a new command "git hook list" to make inspecting hooks easier both for users and for the tests we will add. Further commits will expand on this, e.g. by adding a -z output mode. Signed-off-by: Emily Shaffer <emilyshaffer@google.com> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-02-19hook: run a list of hooks to prepare for multihook supportEmily Shaffer
Hooks are limited to run one command (the default from the hookdir) for each event. This limitation makes it impossible to run multiple commands via config files, which the next commits will add. Implement the ability to run a list of hooks in hook.[ch]. For now, the list contains only one entry representing the "default" hook from the hookdir, so there is no user-visible change in this commit. All hook commands still run sequentially like before. A separate patch series will enable running them in parallel. Signed-off-by: Emily Shaffer <emilyshaffer@google.com> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-02-19hook: add internal state alloc/free callbacksAdrian Ratiu
Some hooks use opaque structs to keep internal state between callbacks. Because hooks ran sequentially (jobs == 1) with one command per hook, these internal states could be allocated on the stack for each hook run. Next commits add the ability to run multiple commands for each hook, so the states cannot be shared or stored on the stack anymore, especially since down the line we will also enable parallel execution (jobs > 1). Add alloc/free helpers for each hook, doing a "deep" alloc/init & free of their internal opaque struct. The alloc callback takes a context pointer, to initialize the struct at at the time of resource acquisition. These callbacks must always be provided together: no alloc without free and no free without alloc, otherwise a BUG() is triggered. Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-01-28hook: add jobs optionAdrian Ratiu
Allow the API callers to specify the number of jobs across which hook execution can be parallelized. It defaults to 1 and no hook currently changes it, so all hooks run sequentially as before. This allows us to both pave the way for parallel hook execution (that will be a follow-up patch series building upon this) and to finish the API conversion of builtin/receive-pack.c, keeping the output async sideband thread ("muxer") design as Peff suggested. When .jobs==1 nothing changes, the "copy_to_sideband" async thread still outputs directly via sideband channel 2, keeping the current (mostly) real-time output characteristics, avoids unnecessary poll delays or deadlock risks. When .jobs > 1, a more complex muxer is needed to buffer the hook output and avoid interleaving. After working on this mux I quickly realized I was re-implementing run-command with ungroup=0 so that idea was dropped in favor of run-command which outputs to stderr. In other words, run-command itself already can buffer/deinterleave pp child outputs (ungroup=0), so we can just connect its stderr to the sideband async task when jobs > 1. Maybe it helps to illustrate how it works with ascii graphics: [ Sequential (jobs = 1) ] [ Parallel (jobs > 1) ] +--------------+ +--------+ +--------+ | Hook Process | | Hook 1 | | Hook 2 | +--------------+ +--------+ +--------+ | | | | stderr (inherited) | stderr pipe | | | (captured) | v v v +-------------------------------------------------------------+ | Parent Process | | | | (direct write) [run-command (buffered)] | | | | | | | | writes | | v v | | +-------------------------------------------+ | | | stderr (FD 2) | | | +-------------------------------------------+ | | | | | | (dup2'd to pipe) | | v | | +-----------------------+ | | | sideband async thread | | | +-----------------------+ | +-------------------------------------------------------------+ When use_sideband == 0, the sideband async thread is missing, so this same architecture just outputs via the parent stderr stream. See the following commits for the hook API conversions doing this, using pre-existing sideband thread logic from `copy_to_sideband`. Suggested-by: Jeff King <peff@peff.net> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-01-28hook: allow separate std[out|err] streamsAdrian Ratiu
The hook API assumes that all hooks merge stdout to stderr. This assumption is proven wrong by pre-push: some of its users actually expect separate stdout and stderr streams and merging them will cause a regression. Therefore this adds a mechanism to allow pre-push to separate the streams, which will be used in the next commit. The mechanism is generic via struct run_hooks_opt just in case there are any more surprise exceptions like this. Reported-by: Chris Darroch <chrisd@apache.org> Suggested-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-01-28hook: provide stdin via callbackEmily Shaffer
This adds a callback mechanism for feeding stdin to hooks alongside the existing path_to_stdin (which slurps a file's content to stdin). The advantage of this new callback is that it can feed stdin without going through the FS layer. This helps when feeding large amount of data and uses the run-command parallel stdin callback introduced in the preceding commit. Signed-off-by: Emily Shaffer <emilyshaffer@google.com> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2026-01-15Revert "Merge branch 'ar/run-command-hook'"Junio C Hamano
This reverts commit f406b8955295d01089ba2baf35eceadff2d11cae, reversing changes made to 1627809eeff75e6ec936fc609e7be46d5eb2fa9e. It seems to have caused a few regressions, two of the three known ones we have proposed solutions for. Let's give ourselves a bit more room to maneuver during the pre-release freeze period and restart once the 2.53 ships.
2025-12-28hooks: allow callers to capture outputEmily Shaffer
Some server-side hooks will require capturing output to send over sideband instead of printing directly to stderr. Expose that capability. Signed-off-by: Emily Shaffer <emilyshaffer@google.com> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-12-28hook: allow overriding the ungroup optionAdrian Ratiu
When calling run_process_parallel() in run_hooks_opt(), the ungroup option is currently hardcoded to .ungroup = 1. This causes problems when ungrouping should be disabled, for example when sideband-reading collated output from child hooks, because sideband-reading and ungrouping are mutually exclusive. Thus a new hook.h option is added to allow overriding. The existing ungroup=1 behavior is preserved in the run_hooks() API and the "hook run" command. We could modify these to take an option if necessary, so I added two code comments there. Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-12-28hook: provide stdin via callbackEmily Shaffer
This adds a callback mechanism for feeding stdin to hooks alongside the existing path_to_stdin (which slurps a file's content to stdin). The advantage of this new callback is that it can feed stdin without going through the FS layer. This helps when feeding large amount of data and uses the run-command parallel stdin callback introduced in the preceding commit. Signed-off-by: Emily Shaffer <emilyshaffer@google.com> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-02-07path: refactor `repo_git_path()` family of functionsPatrick Steinhardt
As explained in an earlier commit, we're refactoring path-related functions to provide a consistent interface for computing paths into the commondir, gitdir and worktree. Refactor the "gitdir" family of functions accordingly. Note that the `repo_git_pathv()` function is converted into an internal implementation detail. It is only used to implement `the_repository` compatibility shims and will eventually be removed from the public interface. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-15Merge branch 'bf/explicit-config-set-in-advice-messages'Junio C Hamano
The advice messages now tell the newer 'git config set' command to set the advice.token configuration variable to squelch a message. * bf/explicit-config-set-in-advice-messages: advice: suggest using subcommand "git config set"
2024-12-06advice: suggest using subcommand "git config set"Bence Ferdinandy
The advice message currently suggests using "git config advice..." to disable advice messages, but since 00bbdde141 (builtin/config: introduce "set" subcommand, 2024-05-06) we have the "set" subcommand for config. Since using the subcommand is more in-line with the modern interface, any advice should be promoting its usage. Change the disable advice message to use the subcommand instead. Change all uses of "git config advice" in the tests to use the subcommand. Signed-off-by: Bence Ferdinandy <bence@ferdinandy.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-13hooks: remove implicit dependency on `the_repository`Patrick Steinhardt
We implicitly depend on `the_repository` in our hook subsystem because we use `strbuf_git_path()` to compute hook paths. Remove this dependency by accepting a `struct repository` as parameter instead. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-24Merge branch 'fixes/2.45.1/2.41' into fixes/2.45.1/2.42Junio C Hamano
* fixes/2.45.1/2.41: Revert "fsck: warn about symlink pointing inside a gitdir" Revert "Add a helper function to compare file contents" clone: drop the protections where hooks aren't run tests: verify that `clone -c core.hooksPath=/dev/null` works again Revert "core.hooksPath: add some protection while cloning" init: use the correct path of the templates directory again hook: plug a new memory leak ci: stop installing "gcc-13" for osx-gcc ci: avoid bare "gcc" for osx-gcc job ci: drop mention of BREW_INSTALL_PACKAGES variable send-email: avoid creating more than one Term::ReadLine object send-email: drop FakeTerm hack
2024-05-24Merge branch 'fixes/2.45.1/2.40' into fixes/2.45.1/2.41Junio C Hamano
* fixes/2.45.1/2.40: Revert "fsck: warn about symlink pointing inside a gitdir" Revert "Add a helper function to compare file contents" clone: drop the protections where hooks aren't run tests: verify that `clone -c core.hooksPath=/dev/null` works again Revert "core.hooksPath: add some protection while cloning" init: use the correct path of the templates directory again hook: plug a new memory leak ci: stop installing "gcc-13" for osx-gcc ci: avoid bare "gcc" for osx-gcc job ci: drop mention of BREW_INSTALL_PACKAGES variable send-email: avoid creating more than one Term::ReadLine object send-email: drop FakeTerm hack
2024-05-24Merge branch 'jc/fix-2.45.1-and-friends-for-2.39' into fixes/2.45.1/2.40Junio C Hamano
Revert overly aggressive "layered defence" that went into 2.45.1 and friends, which broke "git-lfs", "git-annex", and other use cases, so that we can rebuild necessary counterparts in the open. * jc/fix-2.45.1-and-friends-for-2.39: Revert "fsck: warn about symlink pointing inside a gitdir" Revert "Add a helper function to compare file contents" clone: drop the protections where hooks aren't run tests: verify that `clone -c core.hooksPath=/dev/null` works again Revert "core.hooksPath: add some protection while cloning" init: use the correct path of the templates directory again hook: plug a new memory leak ci: stop installing "gcc-13" for osx-gcc ci: avoid bare "gcc" for osx-gcc job ci: drop mention of BREW_INSTALL_PACKAGES variable send-email: avoid creating more than one Term::ReadLine object send-email: drop FakeTerm hack
2024-05-21clone: drop the protections where hooks aren't runJohannes Schindelin
As part of the security bug-fix releases v2.39.4, ..., v2.45.1, I introduced logic to safeguard `git clone` from running hooks that were installed _during_ the clone operation. The rationale was that Git's CVE-2024-32002, CVE-2021-21300, CVE-2019-1354, CVE-2019-1353, CVE-2019-1352, and CVE-2019-1349 should have been low-severity vulnerabilities but were elevated to critical/high severity by the attack vector that allows a weakness where files inside `.git/` can be inadvertently written during a `git clone` to escalate to a Remote Code Execution attack by virtue of installing a malicious `post-checkout` hook that Git will then run at the end of the operation without giving the user a chance to see what code is executed. Unfortunately, Git LFS uses a similar strategy to install its own `post-checkout` hook during a `git clone`; In fact, Git LFS is installing four separate hooks while running the `smudge` filter. While this pattern is probably in want of being improved by introducing better support in Git for Git LFS and other tools wishing to register hooks to be run at various stages of Git's commands, let's undo the clone protections to unbreak Git LFS-enabled clones. This reverts commit 8db1e8743c0 (clone: prevent hooks from running during a clone, 2024-03-28). Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-21hook: plug a new memory leakJohannes Schindelin
In 8db1e8743c0 (clone: prevent hooks from running during a clone, 2024-03-28), I introduced an inadvertent memory leak that was unfortunately not caught before v2.45.1 was released. Here is a fix. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-04-19Sync with 2.41.1Johannes Schindelin
* maint-2.41: (38 commits) Git 2.41.1 Git 2.40.2 Git 2.39.4 fsck: warn about symlink pointing inside a gitdir core.hooksPath: add some protection while cloning init.templateDir: consider this config setting protected clone: prevent hooks from running during a clone Add a helper function to compare file contents init: refactor the template directory discovery into its own function find_hook(): refactor the `STRIP_EXTENSION` logic clone: when symbolic links collide with directories, keep the latter entry: report more colliding paths t5510: verify that D/F confusion cannot lead to an RCE submodule: require the submodule path to contain directories only clone_submodule: avoid using `access()` on directories submodules: submodule paths must not contain symlinks clone: prevent clashing git dirs when cloning submodule in parallel t7423: add tests for symlinked submodule directories has_dir_name(): do not get confused by characters < '/' docs: document security issues around untrusted .git dirs ...
2024-04-19Sync with 2.40.2Johannes Schindelin
* maint-2.40: (39 commits) Git 2.40.2 Git 2.39.4 fsck: warn about symlink pointing inside a gitdir core.hooksPath: add some protection while cloning init.templateDir: consider this config setting protected clone: prevent hooks from running during a clone Add a helper function to compare file contents init: refactor the template directory discovery into its own function find_hook(): refactor the `STRIP_EXTENSION` logic clone: when symbolic links collide with directories, keep the latter entry: report more colliding paths t5510: verify that D/F confusion cannot lead to an RCE submodule: require the submodule path to contain directories only clone_submodule: avoid using `access()` on directories submodules: submodule paths must not contain symlinks clone: prevent clashing git dirs when cloning submodule in parallel t7423: add tests for symlinked submodule directories has_dir_name(): do not get confused by characters < '/' docs: document security issues around untrusted .git dirs upload-pack: disable lazy-fetching by default ...
2024-04-19Sync with 2.39.4Johannes Schindelin
* maint-2.39: (38 commits) Git 2.39.4 fsck: warn about symlink pointing inside a gitdir core.hooksPath: add some protection while cloning init.templateDir: consider this config setting protected clone: prevent hooks from running during a clone Add a helper function to compare file contents init: refactor the template directory discovery into its own function find_hook(): refactor the `STRIP_EXTENSION` logic clone: when symbolic links collide with directories, keep the latter entry: report more colliding paths t5510: verify that D/F confusion cannot lead to an RCE submodule: require the submodule path to contain directories only clone_submodule: avoid using `access()` on directories submodules: submodule paths must not contain symlinks clone: prevent clashing git dirs when cloning submodule in parallel t7423: add tests for symlinked submodule directories has_dir_name(): do not get confused by characters < '/' docs: document security issues around untrusted .git dirs upload-pack: disable lazy-fetching by default fetch/clone: detect dubious ownership of local repositories ...
2024-04-19clone: prevent hooks from running during a cloneJohannes Schindelin
Critical security issues typically combine relatively common vulnerabilities such as case confusion in file paths with other weaknesses in order to raise the severity of the attack. One such weakness that has haunted the Git project in many a submodule-related CVE is that any hooks that are found are executed during a clone operation. Examples are the `post-checkout` and `fsmonitor` hooks. However, Git's design calls for hooks to be disabled by default, as only disabled example hooks are copied over from the templates in `<prefix>/share/git-core/templates/`. As a defense-in-depth measure, let's prevent those hooks from running. Obviously, administrators can choose to drop enabled hooks into the template directory, though, _and_ it is also possible to override `core.hooksPath`, in which case the new check needs to be disabled. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2024-04-17find_hook(): refactor the `STRIP_EXTENSION` logicJohannes Schindelin
When looking for a hook and not finding one, and when `STRIP_EXTENSION` is available (read: if we're on Windows and `.exe` is the required extension for executable programs), we want to look also for a hook with that extension. Previously, we added that handling into the conditional block that was meant to handle when no hook was found (possibly providing some advice for the user's benefit). If the hook with that file extension was found, we'd return early from that function instead of writing out said advice, of course. However, we're about to introduce a safety valve to prevent hooks from being run during a clone, to reduce the attack surface of bugs that allow writing files to be written into arbitrary locations. To prepare for that, refactor the logic to avoid the early return, by separating the `STRIP_EXTENSION` handling from the conditional block handling the case when no hook was found. This commit is best viewed with `--patience`. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2023-06-12abspath: move related functions to abspathCalvin Wan
Move abspath-related functions from strbuf.[ch] to abspath.[ch] so that strbuf is focused on string manipulation routines with minimal dependencies. Signed-off-by: Calvin Wan <calvinwan@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-24hash-ll.h: split out of hash.h to remove dependency on repository.hElijah Newren
hash.h depends upon and includes repository.h, due to the definition and use of the_hash_algo (defined as the_repository->hash_algo). However, most headers trying to include hash.h are only interested in the layout of the structs like object_id. Move the parts of hash.h that do not depend upon repository.h into a new file hash-ll.h (the "low level" parts of hash.h), and adjust other files to use this new header where the convenience inline functions aren't needed. This allows hash.h and object.h to be fairly small, minimal headers. It also exposes a lot of hidden dependencies on both path.h (which was brought in by repository.h) and repository.h (which was previously implicitly brought in by object.h), so also adjust other files to be more explicit about what they depend upon. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-17Merge branch 'jk/unused-post-2.39-part2'Junio C Hamano
More work towards -Wunused. * jk/unused-post-2.39-part2: (21 commits) help: mark unused parameter in git_unknown_cmd_config() run_processes_parallel: mark unused callback parameters userformat_want_item(): mark unused parameter for_each_commit_graft(): mark unused callback parameter rewrite_parents(): mark unused callback parameter fetch-pack: mark unused parameter in callback function notes: mark unused callback parameters prio-queue: mark unused parameters in comparison functions for_each_object: mark unused callback parameters list-objects: mark unused callback parameters mark unused parameters in signal handlers run-command: mark error routine parameters as unused mark "pointless" data pointers in callbacks ref-filter: mark unused callback parameters http-backend: mark unused parameters in virtual functions http-backend: mark argc/argv unused object-name: mark unused parameters in disambiguate callbacks serve: mark unused parameters in virtual functions serve: use repository pointer to get config ls-refs: drop config caching ...
2023-02-24run_processes_parallel: mark unused callback parametersJeff King
Our parallel process API takes several callbacks via function pointers in the run_process_paralell_opts struct. Not every callback needs every parameter; let's mark the unused ones to make -Wunused-parameter happy. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-23treewide: replace cache.h with more direct headers, where possibleElijah Newren
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-08hook API: support passing stdin to hooks, convert am's 'post-rewrite'Emily Shaffer
Convert the invocation of the 'post-rewrite' hook run by 'git am' to use the hook.h library. To do this we need to add a "path_to_stdin" member to "struct run_hooks_opt". In our API this is supported by asking for a file path, rather than by reading stdin. Reading directly from stdin would involve caching the entire stdin (to memory or to disk) once the hook API is made to support "jobs" larger than 1, along with support for executing N hooks at a time (i.e. the upcoming config-based hooks). Signed-off-by: Emily Shaffer <emilyshaffer@google.com> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-10-12run-command API: have run_process_parallel() take an "opts" structÆvar Arnfjörð Bjarmason
As noted in fd3aaf53f71 (run-command: add an "ungroup" option to run_process_parallel(), 2022-06-07) which added the "ungroup" passing it to "run_process_parallel()" via the global "run_processes_parallel_ungroup" variable was a compromise to get the smallest possible regression fix for "maint" at the time. This follow-up to that is a start at passing that parameter and others via a new "struct run_process_parallel_opts", as the earlier version[1] of what became fd3aaf53f71 did. Since we need to change all of the occurrences of "n" to "opt->SOMETHING" let's take the opportunity and rename the terse "n" to "processes". We could also have picked "max_processes", "jobs", "threads" etc., but as the API is named "run_processes_parallel()" let's go with "processes". Since the new "run_processes_parallel()" function is able to take an optional "tr2_category" and "tr2_label" via the struct we can at this point migrate all of the users of "run_processes_parallel_tr2()" over to it. But let's not migrate all the API users yet, only the two users that passed the "ungroup" parameter via the "run_processes_parallel_ungroup" global 1. https://lore.kernel.org/git/cover-v2-0.8-00000000000-20220518T195858Z-avarab@gmail.com/ Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-08-14Merge branch 'ab/hooks-regression-fix'Junio C Hamano
A follow-up fix to a fix for a regression in 2.36. * ab/hooks-regression-fix: hook API: don't segfault on strbuf_addf() to NULL "out"
2022-08-05hook API: don't segfault on strbuf_addf() to NULL "out"Ævar Arnfjörð Bjarmason
Fix a logic error in a082345372e (hook API: fix v2.36.0 regression: hooks should be connected to a TTY, 2022-06-07). When it started using the "ungroup" API added in fd3aaf53f71 (run-command: add an "ungroup" option to run_process_parallel(), 2022-06-07) it should have made the same sort of change that fd3aaf53f71 itself made in "t/helper/test-run-command.c". The correct way to emit this "Couldn't start" output with "ungroup" would be: fprintf(stderr, _("Couldn't start hook '%s'\n"), hook_path); But we should instead remove the emitting of this output. As the added test shows we already emit output when we can't run the child. The "cannot run" output here is emitted by run-command.c's child_err_spew(). So the addition of the "Couldn't start hook" output here in 96e7225b310 (hook: add 'run' subcommand, 2021-12-22) was always redundant. For the pre-commit hook we'll now emit exactly the same output as we did before f443246b9f2 (commit: convert {pre-commit,prepare-commit-msg} hook to hook.h, 2021-12-22) (and likewise for others). We could at this point add this to the pick_next_hook() callbacks in hook.c: assert(!out); assert(!*pp_task_cb); And this to notify_start_failure() and notify_hook_finished() (in the latter case the parameter is called "pp_task_cp"): assert(!out); assert(!pp_task_cb); But let's leave any such instrumentation for some eventual cleanup of the "ungroup" API. Reported-by: Ilya K <me@0upti.me> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Reviewed-by: Emily Shaffer <emilyshaffer@google.com> Reviewed-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-13Merge branch 'ab/hooks-regression-fix'Junio C Hamano
In Git 2.36 we revamped the way how hooks are invoked. One change that is end-user visible is that the output of a hook is no longer directly connected to the standard output of "git" that spawns the hook, which was noticed post release. This is getting corrected. * ab/hooks-regression-fix: hook API: fix v2.36.0 regression: hooks should be connected to a TTY run-command: add an "ungroup" option to run_process_parallel()
2022-06-07hook API: fix v2.36.0 regression: hooks should be connected to a TTYÆvar Arnfjörð Bjarmason
Fix a regression reported[1] against f443246b9f2 (commit: convert {pre-commit,prepare-commit-msg} hook to hook.h, 2021-12-22): Due to using the run_process_parallel() API in the earlier 96e7225b310 (hook: add 'run' subcommand, 2021-12-22) we'd capture the hook's stderr and stdout, and thus lose the connection to the TTY in the case of e.g. the "pre-commit" hook. As a preceding commit notes GNU parallel's similar --ungroup option also has it emit output faster. While we're unlikely to have hooks that emit truly massive amounts of output (or where the performance thereof matters) it's still informative to measure the overhead. In a similar "seq" test we're now ~30% faster: $ cat .git/hooks/seq-hook; git hyperfine -L rev origin/master,HEAD~0 -s 'make CFLAGS=-O3' './git hook run seq-hook' #!/bin/sh seq 100000000 Benchmark 1: ./git hook run seq-hook' in 'origin/master Time (mean ± σ): 787.1 ms ± 13.6 ms [User: 701.6 ms, System: 534.4 ms] Range (min … max): 773.2 ms … 806.3 ms 10 runs Benchmark 2: ./git hook run seq-hook' in 'HEAD~0 Time (mean ± σ): 603.4 ms ± 1.6 ms [User: 573.1 ms, System: 30.3 ms] Range (min … max): 601.0 ms … 606.2 ms 10 runs Summary './git hook run seq-hook' in 'HEAD~0' ran 1.30 ± 0.02 times faster than './git hook run seq-hook' in 'origin/master' 1. https://lore.kernel.org/git/CA+dzEBn108QoMA28f0nC8K21XT+Afua0V2Qv8XkR8rAeqUCCZw@mail.gmail.com/ Reported-by: Anthony Sottile <asottile@umich.edu> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> [jc: minor fix-up to tests for consistency] Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-02run-command API: rename "env_array" to "env"Ævar Arnfjörð Bjarmason
Start following-up on the rename mentioned in c7c4bdeccf3 (run-command API: remove "env" member, always use "env_array", 2021-11-25) of "env_array" to "env". The "env_array" name was picked in 19a583dc39e (run-command: add env_array, an optional argv_array for env, 2014-10-19) because "env" was taken. Let's not forever keep the oddity of "*_array" for this "struct strvec", but not for its "args" sibling. This commit is almost entirely made with a coccinelle rule[1]. The only manual change here is in run-command.h to rename the struct member itself and to change "env_array" to "env" in the CHILD_PROCESS_INIT initializer. The rest of this is all a result of applying [1]: * make contrib/coccinelle/run_command.cocci.patch * patch -p1 <contrib/coccinelle/run_command.cocci.patch * git add -u 1. cat contrib/coccinelle/run_command.pending.cocci @@ struct child_process E; @@ - E.env_array + E.env @@ struct child_process *E; @@ - E->env_array + E->env I've avoided changing any comments and derived variable names here, that will all be done in the next commit. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-07hooks: fix an obscure TOCTOU "did we just run a hook?" raceÆvar Arnfjörð Bjarmason
Fix a Time-of-check to time-of-use (TOCTOU) race in code added in 680ee550d72 (commit: skip discarding the index if there is no pre-commit hook, 2017-08-14). This obscure race condition can occur if we e.g. ran the "pre-commit" hook and it modified the index, but hook_exists() returns false later on (e.g., because the hook itself went away, the directory became unreadable, etc.). Then we won't call discard_cache() when we should have. The race condition itself probably doesn't matter, and users would have been unlikely to run into it in practice. This problem has been noted on-list when 680ee550d72 was discussed[1], but had not been fixed. This change is mainly intended to improve the readability of the code involved, and to make reasoning about it more straightforward. It wasn't as obvious what we were trying to do here, but by having an "invoked_hook" it's clearer that e.g. our discard_cache() is happening because of the earlier hook execution. Let's also change this for the push-to-checkout hook. Now instead of checking if the hook exists and either doing a push to checkout or a push to deploy we'll always attempt a push to checkout. If the hook doesn't exist we'll fall back on push to deploy. The same behavior as before, without the TOCTOU race. See 0855331941b (receive-pack: support push-to-checkout hook, 2014-12-01) for the introduction of the previous behavior. This leaves uses of hook_exists() in two places that matter. The "reference-transaction" check in refs.c, see 67541597670 (refs: implement reference transaction hook, 2020-06-19), and the "prepare-commit-msg" hook, see 66618a50f9c (sequencer: run 'prepare-commit-msg' hook, 2018-01-24). In both of those cases we're saving ourselves CPU time by not preparing data for the hook that we'll then do nothing with if we don't have the hook. So using this "invoked_hook" pattern doesn't make sense in those cases. The "reference-transaction" and "prepare-commit-msg" hook also aren't racy. In those cases we'll skip the hook runs if we race with a new hook being added, whereas in the TOCTOU races being fixed here we were incorrectly skipping the required post-hook logic. 1. https://lore.kernel.org/git/20170810191613.kpmhzg4seyxy3cpq@sigill.intra.peff.net/ Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>