Commit Graph

482 Commits

Author SHA1 Message Date
Caleb White
717af916cd worktree: link worktrees with relative paths
Git currently stores absolute paths to both the main repository and
linked worktrees. However, this causes problems when moving repositories
or working in containerized environments where absolute paths differ
between systems. The worktree links break, and users are required to
manually execute `worktree repair` to repair them, leading to workflow
disruptions. Additionally, mapping repositories inside of containerized
environments renders the repository unusable inside the containers, and
this is not repairable as repairing the worktrees inside the containers
will result in them being broken outside the containers.

To address this, this patch makes Git always write relative paths when
linking worktrees. Relative paths increase the resilience of the
worktree links across various systems and environments, particularly
when the worktrees are self-contained inside the main repository (such
as when using a bare repository with worktrees). This improves
portability, workflow efficiency, and reduces overall breakages.

Although Git now writes relative paths, existing repositories with
absolute paths are still supported. There are no breaking changes
to workflows based on absolute paths, ensuring backward compatibility.

At a low level, the changes involve modifying functions in `worktree.c`
and `builtin/worktree.c` to use `relative_path()` when writing the
worktree’s `.git` file and the main repository’s `gitdir` reference.
Instead of hardcoding absolute paths, Git now computes the relative path
between the worktree and the repository, ensuring that these links are
portable. Locations where these respective file are read have also been
updated to properly handle both absolute and relative paths. Generally,
relative paths are always resolved into absolute paths before any
operations or comparisons are performed.

Additionally, `repair_worktrees_after_gitdir_move()` has been introduced
to address the case where both the `<worktree>/.git` and
`<repo>/worktrees/<id>/gitdir` links are broken after the gitdir is
moved (such as during a re-initialization). This function repairs both
sides of the worktree link using the old gitdir path to reestablish the
correct paths after a move.

The `worktree.path` struct member has also been updated to always store
the absolute path of a worktree. This ensures that worktree consumers
never have to worry about trying to resolve the absolute path themselves.

Signed-off-by: Caleb White <cdwhite3@pm.me>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-08 11:49:22 -07:00
Junio C Hamano
78ce6660bb Merge branch 'ak/typofix-2.46-maint'
Typofix.

* ak/typofix-2.46-maint:
  upload-pack: fix a typo
  sideband: fix a typo
  setup: fix a typo
  run-command: fix a typo
  revision: fix a typo
  refs: fix typos
  rebase: fix a typo
  read-cache-ll: fix a typo
  pretty: fix a typo
  object-file: fix a typo
  merge-ort: fix typos
  merge-ll: fix a typo
  http: fix a typo
  gpg-interface: fix a typo
  git-p4: fix typos
  git-instaweb: fix a typo
  fsmonitor-settings: fix a typo
  diffcore-rename: fix typos
  config.mak.dev: fix a typo
2024-09-25 10:37:12 -07:00
Andrew Kreimer
d1d93ae8b1 setup: fix a typo
Fix a typo in comments.

Signed-off-by: Andrew Kreimer <algonell@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-19 13:46:12 -07:00
Patrick Steinhardt
eafb126456 environment: stop storing "core.logAllRefUpdates" globally
The value of "core.logAllRefUpdates" is being stored in the global
variable `log_all_ref_updates`. This design is somewhat aged nowadays,
where it is entirely possible to access multiple repositories in the
same process which all have different values for this setting. So using
a single global variable to track it is plain wrong.

Remove the global variable. Instead, we now provide a new function part
of the repo-settings subsystem that parses the value for a specific
repository. While that may require us to read the value multiple times,
we work around this by reading it once when the ref backends are set up
and caching the value there.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-12 10:15:43 -07:00
Patrick Steinhardt
a52beae3a3 environment: move set_git_dir() and related into setup layer
The functions `set_git_dir()` and friends are used to set up
repositories. As such, they are quite clearly part of the setup
subsystem, but still live in "environment.c". Move them over, which also
helps to get rid of dependencies on `the_repository` in the environment
subsystem.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-12 10:15:41 -07:00
Patrick Steinhardt
edc2c92624 environment: make get_git_work_tree() accept a repository
The `get_git_work_tree()` function retrieves the path of the work tree
of `the_repository`. Make it accept a `struct repository` such that it
can work on arbitrary repositories and make it part of the repository
subsystem. This reduces our reliance on `the_repository` and clarifies
scope.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-12 10:15:40 -07:00
Patrick Steinhardt
a3673f4898 environment: make get_object_directory() accept a repository
The `get_object_directory()` function retrieves the path to the object
directory for `the_repository`. Make it accept a `struct repository`
such that it can work on arbitrary repositories and make it part of the
repository subsystem. This reduces our reliance on `the_repository` and
clarifies scope.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-12 10:15:39 -07:00
Patrick Steinhardt
661624a4f6 environment: make get_git_common_dir() accept a repository
The `get_git_common_dir()` function retrieves the path to the common
directory for `the_repository`. Make it accept a `struct repository`
such that it can work on arbitrary repositories and make it part of the
repository subsystem. This reduces our reliance on `the_repository` and
clarifies scope.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-12 10:15:39 -07:00
Patrick Steinhardt
246deeac95 environment: make get_git_dir() accept a repository
The `get_git_dir()` function retrieves the path to the Git directory for
`the_repository`. Make it accept a `struct repository` such that it can
work on arbitrary repositories and make it part of the repository
subsystem. This reduces our reliance on `the_repository` and clarifies
scope.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-12 10:15:39 -07:00
Junio C Hamano
2b30d66c43 Merge branch 'jk/mark-unused-parameters'
Mark unused parameters as UNUSED to squelch -Wunused warnings.

* jk/mark-unused-parameters:
  t-hashmap: stop calling setup() for t_intern() test
  scalar: mark unused parameters in dummy function
  daemon: mark unused parameters in non-posix fallbacks
  setup: mark unused parameter in config callback
  test-mergesort: mark unused parameters in trivial callback
  t-hashmap: mark unused parameters in callback function
  reftable: mark unused parameters in virtual functions
  reftable: drop obsolete test function declarations
  reftable: ignore unused argc/argv in test functions
  unit-tests: ignore unused argc/argv
  t/helper: mark more unused argv/argc arguments
  oss-fuzz: mark unused argv/argc argument
  refs: mark unused parameters in do_for_each_reflog_helper()
  refs: mark unused parameters in ref_store fsck callbacks
  update-ref: mark more unused parameters in parser callbacks
  imap-send: mark unused parameter in ssl_socket_connect() fallback
2024-08-26 11:32:23 -07:00
Junio C Hamano
2cf9c2206c Merge branch 'ps/hash-and-ref-format-from-config'
The default object hash and ref backend format used to be settable
only with explicit command line option to "git init" and
environment variables, but now they can be configured in the user's
global and system wide configuration.

* ps/hash-and-ref-format-from-config:
  setup: make ref storage format configurable via config
  setup: make object format configurable via config
  setup: merge configuration of repository formats
  t0001: delete repositories when object format tests finish
  t0001: exercise initialization with ref formats more thoroughly
2024-08-23 09:02:36 -07:00
Jeff King
e2ef77cf7c setup: mark unused parameter in config callback
This is logically a continuation of 783a86c142 (config: mark unused
callback parameters, 2022-08-19), but this case was introduced much
later in 4412a04fe6 (init.templateDir: consider this config setting
protected, 2024-03-29).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-17 09:46:23 -07:00
Patrick Steinhardt
d2511eeae5 setup: make ref storage format configurable via config
Similar to the preceding commit, introduce a new "init.defaultRefFormat"
config that allows the user to globally set the ref storage format used
by newly created repositories.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-16 09:55:22 -07:00
Patrick Steinhardt
0c22e09b73 setup: make object format configurable via config
The object format for repositories can either be configured explicitly
by passing the `--object-format=` option to git-init(1) or git-clone(1),
or globally by setting the `GIT_DEFAULT_HASH` environment variable.
While the former makes sense, setting random environment variables is
not really a good user experience in case someone decides to only use
SHA256 repositories.

It is only natural to expect for a user that things like this can also
be configured via their config. As such, introduce a new config
"init.defaultObjectFormat", similar to "init.defaultBranch", that allows
the user to configure the default object format when creating new repos.

The precedence order now is the following, where the first one wins:

  1. The `--object-format=` switch.

  2. The `GIT_DEFAULT_HASH` environment variable.

  3. The `init.defaultObjectFormat` config variable.

This matches the typical precedence order we use in Git. We typically
let the environment override the config such that the latter can easily
be overridden on an ephemeral basis, for example by scripts.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-16 09:55:21 -07:00
Patrick Steinhardt
39e15b789a setup: merge configuration of repository formats
The configuration of repository formats is split up across two functions
`validate_hash_algorithm()` and `validate_ref_storage_format()`. This is
fine as-is, but we are about to extend the logic to also read default
values from the config. With the logic split across two functions, we
would either have to pass in additional parameters read from the config,
or read the config multiple times. Both of these options feel a bit
unwieldy.

Merge the code into a new function `repository_format_configure()` that
is responsible for configuring the whole repository's format. Like this,
we can easily read the config in a single place, only.

Furthermore, move the calls to `repo_set_ref_storage_format()` and
`repo_set_hash_algo()` into this new function as well, such that all the
logic to configure the repository format is self-contained here.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-16 09:55:21 -07:00
Junio C Hamano
dc0edbb01c safe.directory: normalize the configured path
The pathname of a repository comes from getcwd() and it could be a
path aliased via symbolic links, e.g., the real directory may be
/home/u/repository but a symbolic link /home/u/repo may point at it,
and the clone request may come as "git clone file:///home/u/repo/"

A request to check if /home/u/repository is safe would be rejected
if the safe.directory configuration allows /home/u/repo/ but not its
alias /home/u/repository/.  Normalize the paths configured for the
safe.directory configuration variable before comparing them with the
path being checked.

Two and a half things to note, compared to the previous step to
normalize the actual path of the suspected repository, are:

 - A configured safe.directory may be coming from .gitignore in the
   home directory that may be shared across machines.  The path
   meant to match with an entry may not necessarily exist on all of
   such machines, so not being able to convert them to real path on
   this machine is *not* a condition that is worthy of warning.
   Hence, we ignore a path that cannot be converted to a real path.

 - A configured safe.directory is essentially a random string that
   user throws at us, written completely unrelated to the directory
   the current process happens to be in.  Hence it makes little
   sense to give a non-absolute path.  Hence we ignore any
   non-absolute paths, except for ".".

 - The safe.directory set to "." was once advertised on the list as
   a valid workaround for the regression caused by the overly tight
   safe.directory check introduced in 2.45.1; we treat it to mean
   "if we are at the top level of a repository, it is OK".
   (cf. <834862fd-b579-438a-b9b3-5246bf27ce8a@gmail.com>).

Suggested-by: Phillip Wood <phillip.wood123@gmail.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-07-30 11:47:59 -07:00
Junio C Hamano
7f547c99a6 safe.directory: normalize the checked path
The pathname of a repository comes from getcwd() and it could be a
path aliased via symbolic links, e.g., the real directory may be
/home/u/repository but a symbolic link /home/u/repo may point at it,
and the clone request may come as "git clone file:///home/u/repo/".

A request to check if /home/u/repo is safe would be rejected if the
safe.directory configuration allows /home/u/repository/ but not its
alias /home/u/repo/.  Normalize the path being checked before
comparing with safe.directory value(s).

Suggested-by: Phillip Wood <phillip.wood123@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-07-30 11:47:59 -07:00
Junio C Hamano
1048aa8b7a safe.directory: preliminary clean-up
The paths given in the safe.directory configuration variable are
allowed to contain "~user" (which interpolates to user's home
directory) and "%(prefix)" (which interpolates to the installation
location in RUNTIME_PREFIX-enabled builds, and a call to the
git_config_pathname() function is tasked to obtain a copy of the
path with these constructs interpolated.

The function, when it succeeds, always yields an allocated string in
the location given as the out-parameter; even when there is nothing
to interpolate in the original, a literal copy is made.  The code
path that contains this caller somehow made two contradicting and
incorrect assumptions of the behaviour when there is no need for
interpolation, and was written with extra defensiveness against
two phantom risks that do not exist.

One wrong assumption was that the function might yield NULL when
there is no interpolation.  This led to the use of an extra "check"
variable, conditionally holding either the interpolated or the
original string.  The assumption was with us since 8959555c
(setup_git_directory(): add an owner check for the top-level
directory, 2022-03-02) originally introduced the safe.directory
feature.

Another wrong assumption was that the function might yield the same
pointer as the input when there is no interpolation.  This led to a
conditional free'ing of the interpolated copy, that the conditional
never skipped, as we always received an allocated string.

Simplify the code by removing the extra defensiveness.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-07-30 11:47:58 -07:00
Junio C Hamano
7b472da915 Merge branch 'ps/use-the-repository'
A CPP macro USE_THE_REPOSITORY_VARIABLE is introduced to help
transition the codebase to rely less on the availability of the
singleton the_repository instance.

* ps/use-the-repository:
  hex: guard declarations with `USE_THE_REPOSITORY_VARIABLE`
  t/helper: remove dependency on `the_repository` in "proc-receive"
  t/helper: fix segfault in "oid-array" command without repository
  t/helper: use correct object hash in partial-clone helper
  compat/fsmonitor: fix socket path in networked SHA256 repos
  replace-object: use hash algorithm from passed-in repository
  protocol-caps: use hash algorithm from passed-in repository
  oidset: pass hash algorithm when parsing file
  http-fetch: don't crash when parsing packfile without a repo
  hash-ll: merge with "hash.h"
  refs: avoid include cycle with "repository.h"
  global: introduce `USE_THE_REPOSITORY_VARIABLE` macro
  hash: require hash algorithm in `empty_tree_oid_hex()`
  hash: require hash algorithm in `is_empty_{blob,tree}_oid()`
  hash: make `is_null_oid()` independent of `the_repository`
  hash: convert `oidcmp()` and `oideq()` to compare whole hash
  global: ensure that object IDs are always padded
  hash: require hash algorithm in `oidread()` and `oidclr()`
  hash: require hash algorithm in `hasheq()`, `hashcmp()` and `hashclr()`
  hash: drop (mostly) unused `is_empty_{blob,tree}_sha1()` functions
2024-07-02 09:59:00 -07:00
Junio C Hamano
f0a462ecd5 Merge branch 'tb/precompose-getcwd'
We forgot to normalize the result of getcwd() to NFC on macOS where
all other paths are normalized, which has been corrected.  This still
does not address the case where core.precomposeUnicode configuration
is not defined globally.

* tb/precompose-getcwd:
  macOS: ls-files path fails if path of workdir is NFD
2024-06-24 16:39:14 -07:00
Junio C Hamano
40a163f217 Merge branch 'ps/ref-storage-migration'
A new command has been added to migrate a repository that uses the
files backend for its ref storage to use the reftable backend, with
limitations.

* ps/ref-storage-migration:
  builtin/refs: new command to migrate ref storage formats
  refs: implement logic to migrate between ref storage formats
  refs: implement removal of ref storages
  worktree: don't store main worktree twice
  reftable: inline `merged_table_release()`
  refs/files: fix NULL pointer deref when releasing ref store
  refs/files: extract function to iterate through root refs
  refs/files: refactor `add_pseudoref_and_head_entries()`
  refs: allow to skip creation of reflog entries
  refs: pass storage format to `ref_store_init()` explicitly
  refs: convert ref storage format to an enum
  setup: unset ref storage when reinitializing repository version
2024-06-17 15:55:55 -07:00
Patrick Steinhardt
e7da938570 global: introduce USE_THE_REPOSITORY_VARIABLE macro
Use of the `the_repository` variable is deprecated nowadays, and we
slowly but steadily convert the codebase to not use it anymore. Instead,
callers should be passing down the repository to work on via parameters.

It is hard though to prove that a given code unit does not use this
variable anymore. The most trivial case, merely demonstrating that there
is no direct use of `the_repository`, is already a bit of a pain during
code reviews as the reviewer needs to manually verify claims made by the
patch author. The bigger problem though is that we have many interfaces
that implicitly rely on `the_repository`.

Introduce a new `USE_THE_REPOSITORY_VARIABLE` macro that allows code
units to opt into usage of `the_repository`. The intent of this macro is
to demonstrate that a certain code unit does not use this variable
anymore, and to keep it from new dependencies on it in future changes,
be it explicit or implicit

For now, the macro only guards `the_repository` itself as well as
`the_hash_algo`. There are many more known interfaces where we have an
implicit dependency on `the_repository`, but those are not guarded at
the current point in time. Over time though, we should start to add
guards as required (or even better, just remove them).

Define the macro as required in our code units. As expected, most of our
code still relies on the global variable. Nearly all of our builtins
rely on the variable as there is no way yet to pass `the_repository` to
their entry point. For now, declare the macro in "biultin.h" to keep the
required changes at least a little bit more contained.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-14 10:26:33 -07:00
Junio C Hamano
092b33da2b Merge branch 'ps/ref-storage-migration' into ps/use-the-repository
* ps/ref-storage-migration:
  builtin/refs: new command to migrate ref storage formats
  refs: implement logic to migrate between ref storage formats
  refs: implement removal of ref storages
  worktree: don't store main worktree twice
  reftable: inline `merged_table_release()`
  refs/files: fix NULL pointer deref when releasing ref store
  refs/files: extract function to iterate through root refs
  refs/files: refactor `add_pseudoref_and_head_entries()`
  refs: allow to skip creation of reflog entries
  refs: pass storage format to `ref_store_init()` explicitly
  refs: convert ref storage format to an enum
  setup: unset ref storage when reinitializing repository version
2024-06-13 09:39:08 -07:00
Junio C Hamano
b8bdb2f283 Merge branch 'jc/safe-directory-leading-path'
The safe.directory configuration knob has been updated to
optionally allow leading path matches.

* jc/safe-directory-leading-path:
  safe.directory: allow "lead/ing/path/*" match
2024-06-12 13:37:16 -07:00
Junio C Hamano
cf792653ad Merge branch 'ps/leakfixes'
Leakfixes.

* ps/leakfixes:
  builtin/mv: fix leaks for submodule gitfile paths
  builtin/mv: refactor to use `struct strvec`
  builtin/mv duplicate string list memory
  builtin/mv: refactor `add_slash()` to always return allocated strings
  strvec: add functions to replace and remove strings
  submodule: fix leaking memory for submodule entries
  commit-reach: fix memory leak in `ahead_behind()`
  builtin/credential: clear credential before exit
  config: plug various memory leaks
  config: clarify memory ownership in `git_config_string()`
  builtin/log: stop using globals for format config
  builtin/log: stop using globals for log config
  convert: refactor code to clarify ownership of check_roundtrip_encoding
  diff: refactor code to clarify memory ownership of prefixes
  config: clarify memory ownership in `git_config_pathname()`
  http: refactor code to clarify memory ownership
  checkout: clarify memory ownership in `unique_tracking_name()`
  strbuf: fix leak when `appendwholeline()` fails with EOF
  transport-helper: fix leaking helper name
2024-06-06 12:49:23 -07:00
Patrick Steinhardt
318efb966b refs: convert ref storage format to an enum
The ref storage format is tracked as a simple unsigned integer, which
makes it harder than necessary to discover what that integer actually is
or where its values are defined.

Convert the ref storage format to instead be an enum.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:31 -07:00
Patrick Steinhardt
a83f7f51e1 setup: unset ref storage when reinitializing repository version
When reinitializing a repository's version we may end up unsetting the
hash algorithm when it matches the default hash algorithm. If we didn't
do that then the previously configured value might remain intact.

While the same issue exists for the ref storage extension, we don't do
this here. This has been fine for most of the part because it is not
supported to re-initialize a repository with a different ref storage
format anyway. We're about to introduce a new command to migrate ref
storages though, so this is about to become an issue there.

Prepare for this and unset the ref storage format when reinitializing a
repository with the "files" format.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:31 -07:00
Junio C Hamano
5c7c063c1f Merge branch 'ps/fix-reinit-includeif-onbranch'
"git init" in an already created directory, when the user
configuration has includeif.onbranch, started to fail recently,
which has been corrected.

* ps/fix-reinit-includeif-onbranch:
  setup: fix bug with "includeIf.onbranch" when initializing dir
2024-06-03 13:11:11 -07:00
Torsten Bögershausen
71fa8d2212 macOS: ls-files path fails if path of workdir is NFD
Under macOS, `git ls-files path` does not work (gives an error)
if the absolute 'path' contains characters in NFD (decomposed).
This happens when core.precomposeunicode is true, which is the
most common case. The bug report says:

$ cd somewhere          # some safe place, /tmp or ~/tmp etc.
$ mkdir $'u\xcc\x88'    # ü in NFD
$ cd ü                  # or cd $'u\xcc\x88' or cd $'\xc3\xbc'
$ git init
$ git ls-files $'/somewhere/u\xcc\x88'   # NFD
  fatal: /somewhere/ü: '/somewhere/ü' is outside repository at '/somewhere/ü'
$ git ls-files $'/somewhere/\xc3\xbc'    # NFC
(the same error as above)

In the 'fatal:' error message, there are three ü;
the 1st and 2nd are in NFC, the 3rd is in NFD.

Add test cases that follows the bug report, with the simplification
that the 'ü' is replaced by an 'ä', which is already used as NFD and
NFC in t3910.

The solution is to add a call to precompose_string_if_needed()
to this code in setup.c :
`work_tree = precompose_string_if_needed(get_git_work_tree());`

There is, however, a limitation with this very usage of Git:
The (repo) local .gitconfig file is not used, only the global
"core.precomposeunicode" is taken into account, if it is set (or not).
To set it to true is a good recommendation anyway, and here is the
analyzes from Jun T :

The problem is the_repository->config->hash_initialized
is set to 1 before the_repository->commondir is set to ".git".
Due to this, .git/config is never read, and precomposed_unicode
is never set to 1 (remains -1).

run_builtin() {
    setup_git_directory() {
        strbuf_getcwd() {   # setup.c:1542
            precompose_{strbuf,string}_if_needed() {
                # precomposed_unicode is still -1
                git_congig_get_bool("core.precomposeunicode") {
                    git_config_check_init() {
                        repo_read_config() {
                            git_config_init() {
                                # !!!
                                the_repository->config->hash_initialized=1
                                # !!!
                            }
                            # does not read .git/config since
                            # the_repository->commondir is still NULL
                        }
                    }
                }
                returns without converting to NFC
            }
            returns cwd in NFD
        }

        setup_discovered_git_dir() {
            set_git_work_tree(".") {
                repo_set_worktree() {
                    # this function indirectly calls strbuf_getcwd()
                    # --> precompose_{strbuf,string}_if_needed() -->
                    # {git,repo}_config_get_bool("core.precomposeunicode"),
                    # but does not try to read .git/config since
                    # the_repository->config->hash_initialized
                    # is already set to 1 above. And it will not read
                    # .git/config even if hash_initialized is 0
                    # since the_repository->commondir is still NULL.

                    the_repository->worktree = NFD
                }
            }
        }

        setup_git_env() {
            repo_setup_gitdir() {
                repo_set_commondir() {
                    # finally commondir is set here
                    the_repository->commondir = ".git"
                }
            }
        }

    } // END setup_git_directory

Reported-by: Jun T <takimoto-j@kba.biglobe.ne.jp>
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-31 13:13:40 -07:00
Junio C Hamano
988499e295 Merge branch 'ps/refs-without-the-repository-updates'
Further clean-up the refs subsystem to stop relying on
the_repository, and instead use the repository associated to the
ref_store object.

* ps/refs-without-the-repository-updates:
  refs/packed: remove references to `the_hash_algo`
  refs/files: remove references to `the_hash_algo`
  refs/files: use correct repository
  refs: remove `dwim_log()`
  refs: drop `git_default_branch_name()`
  refs: pass repo when peeling objects
  refs: move object peeling into "object.c"
  refs: pass ref store when detecting dangling symrefs
  refs: convert iteration over replace refs to accept ref store
  refs: retrieve worktree ref stores via associated repository
  refs: refactor `resolve_gitlink_ref()` to accept a repository
  refs: pass repo when retrieving submodule ref store
  refs: track ref stores via strmap
  refs: implement releasing ref storages
  refs: rename `init_db` callback to avoid confusion
  refs: adjust names for `init` and `init_db` callbacks
2024-05-30 14:15:13 -07:00
Junio C Hamano
a60c21b720 Merge branch 'ps/undecided-is-not-necessarily-sha1'
Before discovering the repository details, We used to assume SHA-1
as the "default" hash function, which has been corrected. Hopefully
this will smoke out codepaths that rely on such an unwarranted
assumptions.

* ps/undecided-is-not-necessarily-sha1:
  repository: stop setting SHA1 as the default object hash
  oss-fuzz/commit-graph: set up hash algorithm
  builtin/shortlog: don't set up revisions without repo
  builtin/diff: explicitly set hash algo when there is no repo
  builtin/bundle: abort "verify" early when there is no repository
  builtin/blame: don't access potentially unitialized `the_hash_algo`
  builtin/rev-parse: allow shortening to more than 40 hex characters
  remote-curl: fix parsing of detached SHA256 heads
  attr: fix BUG() when parsing attrs outside of repo
  attr: don't recompute default attribute source
  parse-options-cb: only abbreviate hashes when hash algo is known
  path: move `validate_headref()` to its only user
  path: harden validation of HEAD with non-standard hashes
2024-05-30 14:15:11 -07:00
Junio C Hamano
313eec177a safe.directory: allow "lead/ing/path/*" match
When safe.directory was introduced in v2.30.3 timeframe, 8959555c
(setup_git_directory(): add an owner check for the top-level
directory, 2022-03-02), it only allowed specific opt-out
directories.  Immediately after an embargoed release that included
the change, 0f85c4a3 (setup: opt-out of check with safe.directory=*,
2022-04-13) was done as a response to loosen the check so that a
single '*' can be used to say "I trust all repositories" for folks
who host too many repositories to list individually.

Let's further loosen the check to allow people to say "everything
under this hierarchy is deemed safe" by specifying such a leading
directory with "/*" appended to it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-29 12:06:27 -07:00
Patrick Steinhardt
6073b3b5c3 config: clarify memory ownership in git_config_pathname()
The out parameter of `git_config_pathname()` is a `const char **` even
though we transfer ownership of memory to the caller. This is quite
misleading and has led to many memory leaks all over the place. Adapt
the parameter to instead be `char **`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-27 11:19:59 -07:00
Junio C Hamano
e55f364398 Merge branch 'ps/refs-without-the-repository-updates' into ps/ref-storage-migration
* ps/refs-without-the-repository-updates:
  refs/packed: remove references to `the_hash_algo`
  refs/files: remove references to `the_hash_algo`
  refs/files: use correct repository
  refs: remove `dwim_log()`
  refs: drop `git_default_branch_name()`
  refs: pass repo when peeling objects
  refs: move object peeling into "object.c"
  refs: pass ref store when detecting dangling symrefs
  refs: convert iteration over replace refs to accept ref store
  refs: retrieve worktree ref stores via associated repository
  refs: refactor `resolve_gitlink_ref()` to accept a repository
  refs: pass repo when retrieving submodule ref store
  refs: track ref stores via strmap
  refs: implement releasing ref storages
  refs: rename `init_db` callback to avoid confusion
  refs: adjust names for `init` and `init_db` callbacks
2024-05-23 09:14:08 -07:00
Patrick Steinhardt
407997c1dd setup: fix bug with "includeIf.onbranch" when initializing dir
It was reported that git-init(1) can fail when initializing an existing
directory in case the config contains an "includeIf.onbranch:"
condition:

    $ mkdir repo
    $ git -c includeIf.onbranch:main.path=nonexistent init repo
    BUG: refs.c:2056: reference backend is unknown

The same error can also be triggered when re-initializing an already
existing repository.

The bug has been introduced in 173761e21b (setup: start tracking ref
storage format, 2023-12-29), which wired up the ref storage format. The
root cause is in `init_db()`, which tries to read the config before we
have initialized `the_repository` and most importantly its ref storage
format. We eventually end up calling `include_by_branch()` and execute
`refs_resolve_ref_unsafe()`, but because we have not initialized the ref
storage format yet this will trigger the above bug.

Interestingly, `include_by_branch()` has a mechanism that will only
cause us to resolve the ref when `the_repository->gitdir` is set. This
is also the reason why this only happens when we initialize an already
existing directory or repository: `gitdir` is set in those cases, but
not when creating a new directory.

Now there are two ways to address the issue:

  - We can adapt `include_by_branch()` to also make the code conditional
    on whether `the_repository->ref_storage_format` is set.

  - We can shift around code such that we initialize the repository
    format before we read the config.

While the first approach would be safe, it may also cause us to paper
over issues where a ref store should have been set up. In our case for
example, it may be reasonable to expect that re-initializing the repo
will cause the "onbranch:" condition to trigger, but we would not do
that if the ref storage format was not set up yet. This also used to
work before the above commit that introduced this bug.

Rearrange the code such that we set up the repository format before
reading the config. This fixes the bug and ensures that "onbranch:"
conditions can trigger.

Reported-by: Heghedus Razvan <heghedus.razvan@protonmail.com>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Tested-by: Heghedus Razvan <heghedus.razvan@protonmail.com>
[jc: fixed a test and backported to v2.44.0 codebase]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-22 18:24:48 -07:00
Junio C Hamano
4beb7a3b06 Merge branch 'kn/ref-transaction-symref'
Updates to symbolic refs can now be made as a part of ref
transaction.

* kn/ref-transaction-symref:
  refs: remove `create_symref` and associated dead code
  refs: rename `refs_create_symref()` to `refs_update_symref()`
  refs: use transaction in `refs_create_symref()`
  refs: add support for transactional symref updates
  refs: move `original_update_refname` to 'refs.c'
  refs: support symrefs in 'reference-transaction' hook
  files-backend: extract out `create_symref_lock()`
  refs: accept symref values in `ref_transaction_update()`
2024-05-20 11:20:04 -07:00
Patrick Steinhardt
97abaab5f6 refs: drop git_default_branch_name()
The `git_default_branch_name()` function is a thin wrapper around
`repo_default_branch_name()` with two differences:

  - We implicitly rely on `the_repository`.

  - We cache the default branch name.

None of the callsites of `git_default_branch_name()` are hot code paths
though, so the caching of the branch name is not really required.

Refactor the callsites to use `repo_default_branch_name()` instead and
drop `git_default_branch_name()`, thus getting rid of one more case
where we rely on `the_repository`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-17 10:33:39 -07:00
Patrick Steinhardt
ed93ea1602 refs: rename init_db callback to avoid confusion
Reference backends have two callbacks `init` and `init_db`. The
similarity of these two callbacks has repeatedly confused me whenever I
was looking at them, where I always had to look up which of them does
what.

Rename the `init_db` callback to `create_on_disk`, which should
hopefully be clearer.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-17 10:33:36 -07:00
Junio C Hamano
bca900904d Merge branch 'ps/refs-without-the-repository'
The refs API lost functions that implicitly assumes to work on the
primary ref_store by forcing the callers to pass a ref_store as an
argument.

* ps/refs-without-the-repository:
  refs: remove functions without ref store
  cocci: apply rules to rewrite callers of "refs" interfaces
  cocci: introduce rules to transform "refs" to pass ref store
  refs: add `exclude_patterns` parameter to `for_each_fullref_in()`
  refs: introduce missing functions that accept a `struct ref_store`
2024-05-16 10:10:14 -07:00
Junio C Hamano
46536278a8 Merge branch 'ps/refs-without-the-repository' into ps/refs-without-the-repository-updates
* ps/refs-without-the-repository:
  refs: remove functions without ref store
  cocci: apply rules to rewrite callers of "refs" interfaces
  cocci: introduce rules to transform "refs" to pass ref store
  refs: add `exclude_patterns` parameter to `for_each_fullref_in()`
  refs: introduce missing functions that accept a `struct ref_store`
2024-05-16 09:48:46 -07:00
Patrick Steinhardt
2e5c4758b7 cocci: apply rules to rewrite callers of "refs" interfaces
Apply the rules that rewrite callers of "refs" interfaces to explicitly
pass `struct ref_store`. The resulting patch has been applied with the
`--whitespace=fix` option.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-07 10:06:59 -07:00
Patrick Steinhardt
0c6bd2b81d path: move validate_headref() to its only user
While `validate_headref()` is only called from `is_git_directory()` in
"setup.c", it is currently implemented in "path.c". Move it over such
that it becomes clear that it is only really used during setup in order
to discover repositories.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-06 22:50:48 -07:00
Johannes Schindelin
1c00f92eb5 Sync with 2.44.1
* maint-2.44: (41 commits)
  Git 2.44.1
  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
  ...
2024-04-29 20:42:30 +02:00
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
4412a04fe6 init.templateDir: consider this config setting protected
The ability to configuring the template directory is a delicate feature:
It allows defining hooks that will be run e.g. during a `git clone`
operation, such as the `post-checkout` hook.

As such, it is of utmost importance that Git would not allow that config
setting to be changed during a `git clone` by mistake, allowing an
attacker a chance for a Remote Code Execution, allowing attackers to run
arbitrary code on unsuspecting users' machines.

As a defense-in-depth measure, to prevent minor vulnerabilities in the
`git clone` code from ballooning into higher-serverity attack vectors,
let's make this a protected setting just like `safe.directory` and
friends, i.e. ignore any `init.templateDir` entries from any local
config.

Note: This does not change the behavior of any recursive clone (modulo
bugs), as the local repository config is not even supposed to be written
while cloning the superproject, except in one scenario: If a config
template is configured that sets the template directory. This might be
done because `git clone --recurse-submodules --template=<directory>`
does not pass that template directory on to the submodules'
initialization.

Another scenario where this commit changes behavior is where
repositories are _not_ cloned recursively, and then some (intentional,
benign) automation configures the template directory to be used before
initializing the submodules.

So the caveat is that this could theoretically break existing processes.

In both scenarios, there is a way out, though: configuring the template
directory via the environment variable `GIT_TEMPLATE_DIR`.

This change in behavior is a trade-off between security and
backwards-compatibility that is struck in favor of security.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2024-04-19 12:38:24 +02:00
Johannes Schindelin
df93e407f0 init: refactor the template directory discovery into its own function
We will need to call this function from `hook.c` to be able to prevent
hooks from running that were written as part of a `clone` but did not
originate from the template directory.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2024-04-17 22:30:10 +02:00
Johannes Schindelin
f4aa8c8bb1 fetch/clone: detect dubious ownership of local repositories
When cloning from somebody else's repositories, it is possible that,
say, the `upload-pack` command is overridden in the repository that is
about to be cloned, which would then be run in the user's context who
started the clone.

To remind the user that this is a potentially unsafe operation, let's
extend the ownership checks we have already established for regular
gitdir discovery to extend also to local repositories that are about to
be cloned.

This protection extends also to file:// URLs.

The fixes in this commit address CVE-2024-32004.

Note: This commit does not touch the `fetch`/`clone` code directly, but
instead the function used implicitly by both: `enter_repo()`. This
function is also used by `git receive-pack` (i.e. pushes), by `git
upload-archive`, by `git daemon` and by `git http-backend`. In setups
that want to serve repositories owned by different users than the
account running the service, this will require `safe.*` settings to be
configured accordingly.

Also note: there are tiny time windows where a time-of-check-time-of-use
("TOCTOU") race is possible. The real solution to those would be to work
with `fstat()` and `openat()`. However, the latter function is not
available on Windows (and would have to be emulated with rather
expensive low-level `NtCreateFile()` calls), and the changes would be
quite extensive, for my taste too extensive for the little gain given
that embargoed releases need to pay extra attention to avoid introducing
inadvertent bugs.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2024-04-17 22:29:54 +02:00