Commit Graph

212 Commits (4167c6153b10593b753c4f73eb930b5425e091af)

Author SHA1 Message Date
Junio C Hamano b45113f581 Merge branch 'jk/fetch-follow-remote-head-fix'
"git fetch [<remote>]" with only the configured fetch refspec
should be the only thing to update refs/remotes/<remote>/HEAD,
but the code was overly eager to do so in other cases.

* jk/fetch-follow-remote-head-fix:
  fetch: make set_head() call easier to read
  fetch: don't ask for remote HEAD if followRemoteHEAD is "never"
  fetch: only respect followRemoteHEAD with configured refspecs
2025-04-17 10:28:17 -07:00
Junio C Hamano 9bdd7ecf7e Merge branch 'ps/test-wo-perl-prereq'
"make test" used to have a hard dependency on (basic) Perl; tests
have been rewritten help environment with NO_PERL test the build as
much as possible.

* ps/test-wo-perl-prereq:
  t5703: refactor test to not depend on Perl
  t5316: refactor `max_chain()` to not depend on Perl
  t0210: refactor trace2 scrubbing to not use Perl
  t0021: refactor `generate_random_characters()` to not depend on Perl
  t/lib-httpd: refactor "one-time-perl" CGI script to not depend on Perl
  t/lib-t6000: refactor `name_from_description()` to not depend on Perl
  t/lib-gpg: refactor `sanitize_pgp()` to not depend on Perl
  t: refactor tests depending on Perl for textconv scripts
  t: refactor tests depending on Perl to print data
  t: refactor tests depending on Perl substitution operator
  t: refactor tests depending on Perl transliteration operator
  Makefile: stop requiring Perl when running tests
  meson: stop requiring Perl when tests are enabled
  t: adapt existing PERL prerequisites
  t: introduce PERL_TEST_HELPERS prerequisite
  t: adapt `test_readlink()` to not use Perl
  t: adapt `test_copy_bytes()` to not use Perl
  t: adapt character translation helpers to not use Perl
  t: refactor environment sanitization to not use Perl
  t: skip chain lint when PERL_PATH is unset
2025-04-16 13:54:20 -07:00
Junio C Hamano 518ed014f6 Merge branch 'jt/ref-transaction-abort-fix'
A ref transaction corner case fix.

* jt/ref-transaction-abort-fix:
  builtin/fetch: avoid aborting closed reference transaction
2025-04-16 13:54:17 -07:00
Patrick Steinhardt 23e21a58d5 t: introduce PERL_TEST_HELPERS prerequisite
In the early days of Git, Perl was used quite prominently throughout the
project. This has changed significantly as almost all of the executables
we ship nowadays have eventually been rewritten in C. Only a handful of
subsystems remain that require Perl:

  - gitweb, a read-only web interface.

  - A couple of scripts that allow importing repositories from GNU Arch,
    CVS and Subversion.

  - git-send-email(1), which can be used to send mails.

  - git-request-pull(1), which is used to request somebody to pull from
    a URL by sending an email.

  - git-filter-branch(1), which uses Perl with the `--state-branch`
    option. This command is typically recommended against nowadays in
    favor of git-filter-repo(1).

  - Our Perl bindings for Git.

  - The netrc Git credential helper.

None of these subsystems can really be considered to be part of the
"core" of Git, and an installation without them is fully functional.
It is more likely than not that an end user wouldn't even notice that
any features are missing if those tools weren't installed. But while
Perl nowadays very much is an optional dependency of Git, there is a
significant limitation when Perl isn't available: developers cannot run
our test suite.

Preceding commits have started to lift this restriction by removing the
strict dependency on Perl in many central parts of the test library. But
there are still many tests that rely on small Perl helpers to do various
different things.

Introduce a new PERL_TEST_HELPERS prerequisite that guards all tests
that require Perl. This prerequisite is explicitly different than the
preexisting PERL prerequisite:

  - PERL records whether or not features depending on the Perl
    interpreter are built.

  - PERL_TEST_HELPERS records whether or not a Perl interpreter is
    available for our tests.

By having these two separate prerequisites we can thus distinguish
between tests that inherently depend on Perl because the underlying
feature does, and those tests that depend on Perl because the test
itself is using Perl.

Adapt all tests to set the PERL_TEST_HELPERS prerequisite as needed.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-04-07 14:47:37 -07:00
Justin Tobler b9fadeead7 builtin/fetch: avoid aborting closed reference transaction
As part of the reference transaction commit phase, the transaction is
set to a closed state regardless of whether it was successful of not.
Attempting to abort a closed transaction via `ref_transaction_abort()`
results in a `BUG()`.

In c92abe71df (builtin/fetch: fix leaking transaction with `--atomic`,
2024-08-22), logic to free a transaction after the commit phase is moved
to the centralized exit path. In cases where the transaction commit
failed, this results in a closed transaction being aborted and signaling
a bug.

Free the transaction and set it to NULL when the commit fails. This
allows the exit path to correctly handle the error without attempting to
abort the transaction.

Signed-off-by: Justin Tobler <jltobler@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-03-21 03:59:46 -07:00
Jeff King aab0f899d9 fetch: don't ask for remote HEAD if followRemoteHEAD is "never"
When we are going to consider updating the refs/remotes/*/HEAD symref,
we have to ask the remote side where its HEAD points. But if we know
that the feature is disabled by config, we don't need to bother!

This saves a little bit of work and network communication for the
server. And even a little bit of effort on the client, as our local
set_head() function did a bit of work matching the remote HEAD before
realizing that we're not going to do anything with it.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-03-18 12:21:26 -07:00
Jeff King c834d1a7ce fetch: only respect followRemoteHEAD with configured refspecs
The new followRemoteHEAD feature is triggered for almost every fetch,
causing us to ask the server about the remote "HEAD" and to consider
updating our local tracking HEAD symref. This patch limits the feature
only to the case when we are fetching a remote using its configured
refspecs (typically into its refs/remotes/ hierarchy). There are two
reasons for this.

One is efficiency. E.g., the fixes in 6c915c3f85 (fetch: do not ask for
HEAD unnecessarily, 2024-12-06) and 20010b8c20 (fetch: avoid ls-refs
only to ask for HEAD symref update, 2025-03-08) were aimed at reducing
the work we do when we would not be able to update HEAD anyway. But they
do not quite cover all cases. The remaining one is:

  git fetch origin refs/heads/foo:refs/remotes/origin/foo

which _sometimes_ can update HEAD, but usually not. And that leads us to
the second point, which is being simple and explainable.

The code for updating the tracking HEAD symref requires both that we
learned which ref the remote HEAD points at, and that the server
advertised that ref to us. But because the v2 protocol narrows the
server's advertisement, the command above would not typically update
HEAD at all, unless it happened to point to the "foo" branch. Or even
weirder, it probably _would_ update if the server is very old and
supports only the v0 protocol, which always gives a full advertisement.

This creates confusing behavior for the user: sometimes we may try to
update HEAD and sometimes not, depending on vague rules.

One option here would be to loosen the update code to accept the remote
HEAD even if the server did not advertise that ref. I think that could
work, but it may also lead to interesting corner cases (e.g., creating a
dangling symref locally, even though the branch is not unborn on the
server, if we happen not to have fetched it).

So let's instead simplify the rules: we'll only consider updating the
tracking HEAD symref when we're doing a full fetch of the remote's
configured refs. This is easy to implement; we can just set a flag at
the moment we realize we're using the configured refspecs.  And we can
drop the special case code added by 6c915c3f85 and 20010b8c20, since
this covers those cases. The existing tests from those commits still
pass.

In t5505, an incidental call to "git fetch <remote> <refspec>" updated
HEAD, which caused us to adjust the test in 3f763ddf28 (fetch: set
remote/HEAD if it does not exist, 2024-11-22). We can now adjust that
back to how it was before the feature was added.

Even though t5505 is incidentally testing our new desired behavior,
we'll add an explicit test in t5510 to make sure it is covered.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-03-18 12:21:25 -07:00
Junio C Hamano c3fffcfe8e Merge branch 'bf/fetch-set-head-fix'
Fetching into a bare repository incorrectly assumed it always used
a mirror layout when deciding to update remote-tracking HEAD, which
has been corrected.

* bf/fetch-set-head-fix:
  fetch set_head: fix non-mirror remotes in bare repositories
  fetch set_head: refactor to use remote directly
2025-02-14 17:53:48 -08:00
Junio C Hamano aae91a86fb Merge branch 'ds/name-hash-tweaks'
"git pack-objects" and its wrapper "git repack" learned an option
to use an alternative path-hash function to improve delta-base
selection to produce a packfile with deeper history than window
size.

* ds/name-hash-tweaks:
  pack-objects: prevent name hash version change
  test-tool: add helper for name-hash values
  p5313: add size comparison test
  pack-objects: add GIT_TEST_NAME_HASH_VERSION
  repack: add --name-hash-version option
  pack-objects: add --name-hash-version option
  pack-objects: create new name-hash function version
2025-02-12 10:08:51 -08:00
Junio C Hamano 803b5acaa7 Merge branch 'ps/3.0-remote-deprecation'
Following the procedure we established to introduce breaking
changes for Git 3.0, allow an early opt-in for removing support of
$GIT_DIR/branches/ and $GIT_DIR/remotes/ directories to configure
remotes.

* ps/3.0-remote-deprecation:
  remote: announce removal of "branches/" and "remotes/"
  builtin/pack-redundant: remove subcommand with breaking changes
  ci: repurpose "linux-gcc" job for deprecations
  ci: merge linux-gcc-default into linux-gcc
  Makefile: wire up build option for deprecated features
2025-02-03 10:23:33 -08:00
Derrick Stolee ce961135cc pack-objects: add GIT_TEST_NAME_HASH_VERSION
Add a new environment variable to opt-in to different values of the
--name-hash-version=<n> option in 'git pack-objects'. This allows for
extra testing of the feature without repeating all of the test
scenarios. Unlike many GIT_TEST_* variables, we are choosing to not add
this to the linux-TEST-vars CI build as that test run is already
overloaded. The behavior exposed by this test variable is of low risk
and should be sufficient to allow manual testing when an issue arises.

But this option isn't free. There are a few tests that change behavior
with the variable enabled.

First, there are a few tests that are very sensitive to certain delta
bases being picked. These are both involving the generation of thin
bundles and then counting their objects via 'git index-pack --fix-thin'
which pulls the delta base into the new packfile. For these tests,
disable the option as a decent long-term option.

Second, there are some tests that compare the exact output of a 'git
pack-objects' process when using bitmaps. The warning that ignores the
--name-hash-version=2 and forces version 1 causes these tests to fail.
Disable the environment variable to get around this issue.

Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-27 13:21:43 -08:00
Bence Ferdinandy 93dc16483a fetch set_head: fix non-mirror remotes in bare repositories
In b1b713f722 (fetch set_head: handle mirrored bare repositories,
2024-11-22) it was implicitly assumed that all remotes will be mirrors
in a bare repository, thus fetching a non-mirrored remote could lead to
HEAD pointing to a non-existent reference. Make sure we only overwrite
HEAD if we are in a bare repository and fetching from a mirror.
Otherwise, proceed as normally, and create
refs/remotes/<nonmirrorremote>/HEAD instead.

Reported-by: Christian Hesse <list@eworm.de>
Signed-off-by: Bence Ferdinandy <bence@ferdinandy.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-27 08:16:47 -08:00
Patrick Steinhardt 8ccc75c245 remote: announce removal of "branches/" and "remotes/"
Back when Git was in its infancy, remotes were configured via separate
files in "branches/" (back in 2005). This mechanism was replaced later
that year with the "remotes/" directory. Both mechanisms have eventually
been replaced by config-based remotes, and it is very unlikely that
anybody still uses these directories to configure their remotes.

Both of these directories have been marked as deprecated, one in 2005
and the other one in 2011. Follow through with the deprecation and
finally announce the removal of these features in Git 3.0.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
[jc: with a small tweak to the help message]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-24 08:08:56 -08:00
Junio C Hamano a1f34d5955 Merge branch 'bf/fetch-set-head-config'
"git fetch" honors "remote.<remote>.followRemoteHEAD" settings to
tweak the remote-tracking HEAD in "refs/remotes/<remote>/HEAD".

* bf/fetch-set-head-config:
  remote set-head: set followRemoteHEAD to "warn" if "always"
  fetch set_head: add warn-if-not-$branch option
  fetch set_head: move warn advice into advise_if_enabled
  fetch: add configuration for set_head behaviour
2024-12-19 10:58:30 -08:00
Junio C Hamano ae75cefd94 Merge branch 'jc/set-head-symref-fix'
"git fetch" from a configured remote learned to update a missing
remote-tracking HEAD but it asked the remote about their HEAD even
when it did not need to, which has been corrected.  Incidentally,
this also corrects "git fetch --tags $URL" which was broken by the
new feature in an unspecified way.

* jc/set-head-symref-fix:
  fetch: do not ask for HEAD unnecessarily
2024-12-19 10:58:28 -08:00
Junio C Hamano 5f212684ab Merge branch 'bf/set-head-symref'
When "git fetch $remote" notices that refs/remotes/$remote/HEAD is
missing and discovers what branch the other side points with its
HEAD, refs/remotes/$remote/HEAD is updated to point to it.

* bf/set-head-symref:
  fetch set_head: handle mirrored bare repositories
  fetch: set remote/HEAD if it does not exist
  refs: add create_only option to refs_update_symref_extended
  refs: add TRANSACTION_CREATE_EXISTS error
  remote set-head: better output for --auto
  remote set-head: refactor for readability
  refs: atomically record overwritten ref in update_symref
  refs: standardize output of refs_read_symbolic_ref
  t/t5505-remote: test failure of set-head
  t/t5505-remote: set default branch to main
2024-12-19 10:58:27 -08:00
Junio C Hamano 6c915c3f85 fetch: do not ask for HEAD unnecessarily
In 3f763ddf28 (fetch: set remote/HEAD if it does not exist,
2024-11-22), git-fetch learned to opportunistically set $REMOTE/HEAD
when fetching by always asking for remote HEAD, in the hope that it
will help setting refs/remotes/<name>/HEAD if missing.

But it is not needed to always ask for remote HEAD.  When we are
fetching from a remote, for which we have remote-tracking branches,
we do need to know about HEAD.  But if we are doing one-shot fetch,
e.g.,

  $ git fetch --tags https://github.com/git/git

we do not even know what sub-hierarchy of refs/remotes/<remote>/
we need to adjust the remote HEAD for.  There is no need to ask for
HEAD in such a case.

Incidentally, because the unconditional request to list "HEAD"
affected the number of ref-prefixes requested in the ls-remote
request, this affected how the requests for tags are added to the
same ls-remote request, breaking "git fetch --tags $URL" performed
against a URL that is not configured as a remote.

Reported-by: Josh Steadmon <steadmon@google.com>
[jc: tests are also borrowed from Josh's patch]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-07 21:58:59 +09:00
Bence Ferdinandy 9e2b7005be fetch set_head: add warn-if-not-$branch option
Currently if we want to have a remote/HEAD locally that is different
from the one on the remote, but we still want to get a warning if remote
changes HEAD, our only option is to have an indiscriminate warning with
"follow_remote_head" set to "warn". Add a new option
"warn-if-not-$branch", where $branch is a branch name we do not wish to
get a warning about. If the remote HEAD is $branch do not warn,
otherwise, behave as "warn".

E.g. let's assume, that our remote origin has HEAD
set to "master", but locally we have "git remote set-head origin seen".
Setting 'remote.origin.followRemoteHEAD = "warn"' will always print
a warning, even though the remote has not changed HEAD from "master".
Setting 'remote.origin.followRemoteHEAD = "warn-if-not-master" will
squelch the warning message, unless the remote changes HEAD from
"master". Note, that should the remote change HEAD to "seen" (which we
have locally), there will still be no warning.

Improve the advice message in report_set_head to also include silencing
the warning message with "warn-if-not-$branch".

Signed-off-by: Bence Ferdinandy <bence@ferdinandy.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-06 02:59:40 +09:00
Bence Ferdinandy ad739f525e fetch set_head: move warn advice into advise_if_enabled
Advice about what to do when getting a warning is typed out explicitly
twice and is printed as regular output. The output is also tested for.
Extract the advice message into a single place and use a wrapper
function, so if later the advice is made more chatty the signature only
needs to be changed in once place. Remove the testing for the advice
output in the tests.

Signed-off-by: Bence Ferdinandy <bence@ferdinandy.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-06 02:59:16 +09:00
Bence Ferdinandy b7f7d16562 fetch: add configuration for set_head behaviour
In the current implementation, if refs/remotes/$remote/HEAD does not
exist, running fetch will create it, but if it does exist it will not do
anything, which is a somewhat safe and minimal approach. Unfortunately,
for users who wish to NOT have refs/remotes/$remote/HEAD set for any
reason (e.g. so that `git rev-parse origin` doesn't accidentally point
them somewhere they do not want to), there is no way to remove this
behaviour. On the other side of the spectrum, users may want fetch to
automatically update HEAD or at least give them a warning if something
changed on the remote.

Introduce a new setting, remote.$remote.followRemoteHEAD with four
options:

    - "never": do not ever do anything, not even create
    - "create": the current behaviour, now the default behaviour
    - "warn": print a message if remote and local HEAD is different
    - "always": silently update HEAD on every change

Signed-off-by: Bence Ferdinandy <bence@ferdinandy.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-02 09:55:17 +09:00
Bence Ferdinandy 3f763ddf28 fetch: set remote/HEAD if it does not exist
When cloning a repository remote/HEAD is created, but when the user
creates a repository with git init, and later adds a remote, remote/HEAD
is only created if the user explicitly runs a variant of "remote
set-head". Attempt to set remote/HEAD during fetch, if the user does not
have it already set. Silently ignore any errors.

Signed-off-by: Bence Ferdinandy <bence@ferdinandy.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-25 11:46:37 +09:00
Patrick Steinhardt fc1ddf42af t: remove TEST_PASSES_SANITIZE_LEAK annotations
Now that the default value for TEST_PASSES_SANITIZE_LEAK is `true` there
is no longer a need to have that variable declared in all of our tests.
Drop it.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-21 08:23:48 +09:00
Patrick Steinhardt 13b23d2da5 transport: fix leaking negotiation tips
We do not free negotiation tips in the transport's smart options. Fix
this by freeing them on disconnect.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-22 09:18:06 -07:00
Junio C Hamano 16a592f132 Merge branch 'ps/pseudo-ref-terminology'
Terminology to call various ref-like things are getting
straightened out.

* ps/pseudo-ref-terminology:
  refs: refuse to write pseudorefs
  ref-filter: properly distinuish pseudo and root refs
  refs: pseudorefs are no refs
  refs: classify HEAD as a root ref
  refs: do not check ref existence in `is_root_ref()`
  refs: rename `is_special_ref()` to `is_pseudo_ref()`
  refs: rename `is_pseudoref()` to `is_root_ref()`
  Documentation/glossary: define root refs as refs
  Documentation/glossary: clarify limitations of pseudorefs
  Documentation/glossary: redefine pseudorefs as special refs
2024-05-28 11:17:06 -07:00
Junio C Hamano 86a49253a6 Merge branch 'it/refs-name-conflict'
Expose "name conflict" error when a ref creation fails due to D/F
conflict in the ref namespace, to improve an error message given by
"git fetch".

* it/refs-name-conflict:
  refs: return conflict error when checking packed refs
2024-05-23 11:04:27 -07:00
Patrick Steinhardt 8e4f5c2dc2 refs: refuse to write pseudorefs
Pseudorefs are not stored in the ref database as by definition, they
carry additional metadata that essentially makes them not a ref. As
such, writing pseudorefs via the ref backend does not make any sense
whatsoever as the ref backend wouldn't know how exactly to store the
data.

Restrict writing pseudorefs via the ref backend.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-15 07:30:52 -07:00
Ivan Tse 9339fca23e refs: return conflict error when checking packed refs
The TRANSACTION_NAME_CONFLICT error code refers to a failure to create a
ref due to a name conflict with another ref. An example of this is a
directory/file conflict such as ref names A/B and A.

"git fetch" uses this error code to more accurately describe the error
by recommending to the user that they try running "git remote prune" to
remove any old refs that are deleted by the remote which would clear up
any directory/file conflicts.

This helpful error message is not displayed when the conflicted ref is
stored in packed refs. This change fixes this by ensuring error return
code consistency in `lock_raw_ref`.

Signed-off-by: Ivan Tse <ivan.tse1@gmail.com>
Acked-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-06 08:48:25 -07:00
Johannes Schindelin e5e6663e69 Sync with 2.43.4
* maint-2.43: (40 commits)
  Git 2.43.4
  Git 2.42.2
  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
  ...
2024-04-19 12:38:54 +02:00
Johannes Schindelin 8e97ec3662 Sync with 2.42.2
* maint-2.42: (39 commits)
  Git 2.42.2
  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 < '/'
  ...
2024-04-19 12:38:50 +02:00
Johannes Schindelin be348e9815 Sync with 2.41.1
* 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
  ...
2024-04-19 12:38:46 +02:00
Johannes Schindelin f5b2af06f5 Sync with 2.40.2
* 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
  ...
2024-04-19 12:38:42 +02:00
Johannes Schindelin 93a88f42db Sync with 2.39.4
* 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
  ...
2024-04-19 12:38:37 +02:00
Johannes Schindelin e4930e86c0 t5510: verify that D/F confusion cannot lead to an RCE
The most critical vulnerabilities in Git lead to a Remote Code Execution
("RCE"), i.e. the ability for an attacker to have malicious code being
run as part of a Git operation that is not expected to run said code,
such has hooks delivered as part of a `git clone`.

A couple of parent commits ago, a bug was fixed that let Git be confused
by the presence of a path `a-` to mistakenly assume that a directory
`a/` can safely be created without removing an existing `a` that is a
symbolic link.

This bug did not represent an exploitable vulnerability on its
own; Let's make sure it stays that way.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2024-04-17 22:30:06 +02:00
Junio C Hamano 1685e9ffe6 Merge branch 'jk/commit-graph-slab-clear-fix' into maint-2.43
Clearing in-core repository (happens during e.g., "git fetch
--recurse-submodules" with commit graph enabled) made in-core
commit object in an inconsistent state by discarding the necessary
data from commit-graph too early, which has been corrected.

* jk/commit-graph-slab-clear-fix:
  commit-graph: retain commit slab when closing NULL commit_graph
2024-02-08 16:22:05 -08:00
Junio C Hamano 4cc0f8e8fa Merge branch 'jk/commit-graph-slab-clear-fix'
Clearing in-core repository (happens during e.g., "git fetch
--recurse-submodules" with commit graph enabled) made in-core
commit object in an inconsistent state by discarding the necessary
data from commit-graph too early, which has been corrected.

* jk/commit-graph-slab-clear-fix:
  commit-graph: retain commit slab when closing NULL commit_graph
2024-01-16 10:11:58 -08:00
Jeff King d70f554cdf commit-graph: retain commit slab when closing NULL commit_graph
This fixes a regression introduced in ac6d45d11f (commit-graph: move
slab-clearing to close_commit_graph(), 2023-10-03), in which running:

  git -c fetch.writeCommitGraph=true fetch --recurse-submodules

multiple times in a freshly cloned repository causes a segfault. What
happens in the second (and subsequent) runs is this:

  1. We make a "struct commit" for any ref tips which we're storing
     (even if we already have them, they still go into FETCH_HEAD).

     Because the first run will have created a commit graph, we'll find
     those commits in the graph.

     The commit struct is therefore created with a NULL "maybe_tree"
     entry, because we can load its oid from the graph later. But to do
     that we need to remember that we got the commit from the graph,
     which is recorded in a global commit_graph_data_slab object.

  2. Because we're using --recurse-submodules, we'll try to fetch each
     of the possible submodules. That implies creating a separate
     "struct repository" in-process for each submodule, which will
     require a later call to repo_clear().

     The call to repo_clear() calls raw_object_store_clear(), which in
     turn calls close_object_store(), which in turn calls
     close_commit_graph(). And the latter frees the commit graph data
     slab.

  3. Later, when trying to write out a new commit graph, we'll ask for
     their tree oid via get_commit_tree_oid(), which will see that the
     object is parsed but with a NULL maybe_tree field. We'd then
     usually pull it from the graph file, but because the slab was
     cleared, we don't realize that we can do so! We end up returning
     NULL and segfaulting.

     (It seems questionable that we'd write a graph entry for such a
     commit anyway, since we know we already have one. I didn't
     double-check, but that may simply be another side effect of having
     cleared the slab).

The bug is in step (2) above. We should not be clearing the slab when
cleaning up the submodule repository structs. Prior to ac6d45d11f, we
did not do so because it was done inside a helper function that returned
early when it saw NULL. So the behavior change from that commit is that
we'll now _always_ clear the slab via repo_clear(), even if the
repository being closed did not have a commit graph (and thus would have
a NULL commit_graph struct).

The most immediate fix is to add in a NULL check in close_commit_graph(),
making it a true noop when passed in an object_store with a NULL
commit_graph (it's OK to just return early, since the rest of its code
is already a noop when passed NULL). That restores the pre-ac6d45d11f
behavior. And that's what this patch does, along with a test that
exercises it (we already have a test that uses submodules along with
fetch.writeCommitGraph, but the bug only triggers when there is a
subsequent fetch and when that fetch uses --recurse-submodules).

So that fixes the regression in the least-risky way possible.

I do think there's some fragility here that we might want to follow up
on. We have a global commit_graph_data_slab that contains graph
positions, and our global commit structs depend on the that slab
remaining valid. But close_commit_graph() is just about closing _one_
object store's graph. So it's dangerous to call that function and clear
the slab without also throwing away any "struct commit" we might have
parsed that depends on it.

Which at first glance seems like a bug we could already trigger. In the
situation described here, there is no commit graph in the submodule
repository, so our commit graph is NULL (in fact, in our test script
there is no submodule repo at all, so we immediately return from
repo_init() and call repo_clear() only to free up memory). But what
would happen if there was one? Wouldn't we see a non-NULL commit_graph
entry, and then clear the global slab anyway?

The answer is "no", but for very bizarre reasons. Remember that
repo_clear() calls raw_object_store_clear(), which then calls
close_object_store() and thus close_commit_graph(). But before it does
so, raw_object_store_clear() does something else: it frees the commit
graph and sets it to NULL! So by this code path we'll _never_ see a
non-NULL commit_graph struct, and thus never clear the slab.

So it happens to work out. But it still seems questionable to me that we
would clear a global slab (which might still be in use) when closing the
commit graph. This clearing comes from 957ba814bf (commit-graph: when
closing the graph, also release the slab, 2021-09-08), and was fixing a
case where we really did need it to be closed (and in that case we
presumably call close_object_store() more directly).

So I suspect there may still be a bug waiting to happen there, as any
object loaded before the call to close_object_store() may be stranded
with a bogus maybe_tree entry (and thus looking at it after the call
might cause an error). But I'm not sure how to trigger it, nor what the
fix should look like (you probably would need to "unparse" any objects
pulled from the graph). And so this patch punts on that for now in favor
of fixing the recent regression in the most direct way, which should not
have any other fallouts.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-01-05 08:35:26 -08:00
Patrick Steinhardt b02c7646f4 t5510: ensure that the packed-refs file needs locking
One of the tests in t5510 asserts that a `git fetch --prune` detects
failures to prune branches. This is done by locking the packed-refs
file, which would then later lead to a locking issue when Git tries to
rewrite the file to prune the branches from it.

Interestingly though, we do not pack the about-to-be-pruned branch into
the packed-refs file, so it never even contained that branch in the
first place. While this is good enough right now because the pruning
will always lock the file regardless of whether it contains the branch
or not, this is a mere implementation detail. In fact, we're about to
rewrite branch deletions to make use of the ref transaction interface,
which knows to skip rewrites of the packed-refs file in the case where
it does not contain the branches in the first place, and this will break
the test.

Prepare the test for that change by packing the refs before trying to
prune them.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-11-17 10:12:12 +09:00
Junio C Hamano a8e2394704 Merge branch 'jc/test-i18ngrep'
Another step to deprecate test_i18ngrep.

* jc/test-i18ngrep:
  tests: teach callers of test_i18ngrep to use test_grep
  test framework: further deprecate test_i18ngrep
2023-11-08 11:04:02 +09:00
Junio C Hamano 6789275d37 tests: teach callers of test_i18ngrep to use test_grep
They are equivalents and the former still exists, so as long as the
only change this commit makes are to rewrite test_i18ngrep to
test_grep, there won't be any new bug, even if there still are
callers of test_i18ngrep remaining in the tree, or when merged to
other topics that add new uses of test_i18ngrep.

This patch was produced more or less with

    git grep -l -e 'test_i18ngrep ' 't/t[0-9][0-9][0-9][0-9]-*.sh' |
    xargs perl -p -i -e 's/test_i18ngrep /test_grep /'

and a good way to sanity check the result yourself is to run the
above in a checkout of c4603c1c (test framework: further deprecate
test_i18ngrep, 2023-10-31) and compare the resulting working tree
contents with the result of applying this patch to the same commit.
You'll see that test_i18ngrep in a few t/lib-*.sh files corrected,
in addition to the manual reproduction.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-11-02 17:13:44 +09:00
Junio C Hamano f3d33f8cfe transfer.unpackLimit: fetch/receive.unpackLimit takes precedence
The transfer.unpackLimit configuration variable is documented to be
used only as a fallback value when the more operation-specific
fetch.unpackLimit and receive.unpackLimit variables are not set, but
the implementation had the precedence reversed.  Apparently this was
broken since the transfer.unpackLimit was introduced in e28714c5
(Consolidate {receive,fetch}.unpackLimit, 2007-01-24).

Often when documentation and code have diverged for so long, we
prefer to change the documentation instead, to avoid disrupting
users.  But doing so would make these weirdly unlike most other
"specific overrides general" config options. And the fact that the
bug has existed for so long without anyone noticing implies to me
that nobody really tries to mix and match them much.

Signed-off-by: Taylor Santiago <taylorsantiago@google.com>
[jc: rewrote the log message, added tests, covered receive-pack as well]
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-08-22 18:30:49 -07:00
Patrick Steinhardt 2c5691d6cf fetch: split out tests for output format
We're about to introduce a new porcelain mode for the output of
git-fetch(1). As part of that we'll be introducing a set of new tests
that only relate to the output of this command.

Split out tests that exercise the output format of git-fetch(1) so that
it becomes easier to verify this functionality as a standalone unit. As
the tests assume that the default branch is called "main" we set up the
corresponding GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME environment variable
accordingly.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-05-10 10:35:24 -07:00
Eric Wong c6ce27ab08 fetch: support hideRefs to speed up connectivity checks
With roughly 800 remotes all fetching into their own
refs/remotes/$REMOTE/* island, the connectivity check[1] gets
expensive for each fetch on systems which lack sufficient RAM to
cache objects.

To do a no-op fetch on one $REMOTE out of hundreds, hideRefs now
allows the no-op fetch to take ~30 seconds instead of ~20 minutes
on a noisy, RAM-constrained machine (localhost, so no network latency):

   git -c fetch.hideRefs=refs \
	-c fetch.hideRefs='!refs/remotes/$REMOTE/' \
	fetch $REMOTE

[1] `git rev-list --objects --stdin --not --all --quiet --alternate-refs'

Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-27 09:27:03 -08:00
Calvin Wan d390e08076 Documentation: clarify multiple pushurls vs urls
In a remote with multiple configured URLs, `git remote -v` shows the
correct url that fetch uses. However, `git config remote.<remote>.url`
returns the last defined url instead. This discrepancy can cause
confusion for users with a remote defined as such, since any url
defined after the first essentially acts as a pushurl.

Add documentation to clarify how fetch interacts with multiple urls
and how push interacts with multiple pushurls and urls.

Add test affirming interaction between fetch and multiple urls.

Signed-off-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-07 11:02:27 -08:00
Taylor Blau f2798aa404 Sync with 2.36.3
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-10-06 19:58:16 -04:00
Taylor Blau 58612f82b6 Sync with 2.35.5
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-10-06 17:44:44 -04:00
Taylor Blau ac8a1db867 Sync with 2.34.5
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-10-06 17:43:37 -04:00
Taylor Blau 3957f3c84e Sync with 2.32.4
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-10-06 17:42:02 -04:00
Taylor Blau 122512967e Sync with 2.30.6
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-10-06 17:39:15 -04:00
Taylor Blau 225d2d50cc t/t5NNN: allow local submodules
To prepare for the default value of `protocol.file.allow` to change to
"user", ensure tests that rely on local submodules can initialize them
over the file protocol.

Tests that only need to interact with submodules in a limited capacity
have individual Git commands annotated with the appropriate
configuration via `-c`. Tests that interact with submodules a handful of
times use `test_config_global` instead. Test scripts that rely on
submodules throughout use a `git config --global` during a setup test
towards the beginning of the script.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-10-01 00:23:38 -04:00
Derrick Stolee 2ffb7d13ee t5510: replace 'origin' with URL more carefully
The many test_configured_prune tests in t5510-fetch.sh test many
combinations of --prune, --prune-tags, and using 'origin' or an explicit
URL. Some machinery was introduced in e1790f9245 (fetch tests: fetch
<url> <spec> as well as fetch [<remote>], 2018-02-09) to replace
'origin' with this explicit URL. This URL is a "file:///" URL for the
root of the $TRASH_DIRECTORY.

However, if the current build tree has an '@' symbol, the
replacement using perl fails. It drops the '@' as well as anything
else in that directory name.  You can observe this locally by
cloning git.git into a "victim@03" directory and running the test
script.

As we are writing in Perl anyway, pass in the shell variables involved
to the script as arguments and perform necessary string transformations
inside it, instead of assuming that it is sufficient to enclose the
$remote_url variable inside a pair of single quotes.

Reported-by: Randall Becker <rsbecker@nexbridge.com>
Original-patch-by: Derrick Stolee <derrickstolee@github.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-21 10:35:38 -07:00