Commit Graph

353 Commits

Author SHA1 Message Date
Johannes Schindelin
fc0c773028 Sync with 2.31.4
* maint-2.31:
  Git 2.31.4
  Git 2.30.5
  setup: tighten ownership checks post CVE-2022-24765
  git-compat-util: allow root to access both SUDO_UID and root owned
  t0034: add negative tests and allow git init to mostly work under sudo
  git-compat-util: avoid failing dir ownership checks if running privileged
  t: regression git needs safe.directory when using sudo
2022-06-23 12:35:30 +02:00
Carlo Marcelo Arenas Belón
3b0bf27049 setup: tighten ownership checks post CVE-2022-24765
8959555cee (setup_git_directory(): add an owner check for the top-level
directory, 2022-03-02), adds a function to check for ownership of
repositories using a directory that is representative of it, and ways to
add exempt a specific repository from said check if needed, but that
check didn't account for owership of the gitdir, or (when used) the
gitfile that points to that gitdir.

An attacker could create a git repository in a directory that they can
write into but that is owned by the victim to work around the fix that
was introduced with CVE-2022-24765 to potentially run code as the
victim.

An example that could result in privilege escalation to root in *NIX would
be to set a repository in a shared tmp directory by doing (for example):

  $ git -C /tmp init

To avoid that, extend the ensure_valid_ownership function to be able to
check for all three paths.

This will have the side effect of tripling the number of stat() calls
when a repository is detected, but the effect is expected to be likely
minimal, as it is done only once during the directory walk in which Git
looks for a repository.

Additionally make sure to resolve the gitfile (if one was used) to find
the relevant gitdir for checking.

While at it change the message printed on failure so it is clear we are
referring to the repository by its worktree (or gitdir if it is bare) and
not to a specific directory.

Helped-by: Junio C Hamano <junio@pobox.com>
Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
2022-06-23 12:31:05 +02:00
Junio C Hamano
1530434434 Git 2.32.2
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-04-13 15:21:26 -07:00
Derrick Stolee
0f85c4a30b setup: opt-out of check with safe.directory=*
With the addition of the safe.directory in 8959555ce
(setup_git_directory(): add an owner check for the top-level directory,
2022-03-02) released in v2.35.2, we are receiving feedback from a
variety of users about the feature.

Some users have a very large list of shared repositories and find it
cumbersome to add this config for every one of them.

In a more difficult case, certain workflows involve running Git commands
within containers. The container boundary prevents any global or system
config from communicating `safe.directory` values from the host into the
container. Further, the container almost always runs as a different user
than the owner of the directory in the host.

To simplify the reactions necessary for these users, extend the
definition of the safe.directory config value to include a possible '*'
value. This value implies that all directories are safe, providing a
single setting to opt-out of this protection.

Note that an empty assignment of safe.directory clears all previous
values, and this is already the case with the "if (!value || !*value)"
condition.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-04-13 12:42:51 -07:00
Matheus Valadares
bb50ec3cc3 setup: fix safe.directory key not being checked
It seems that nothing is ever checking to make sure the safe directories
in the configs actually have the key safe.directory, so some unrelated
config that has a value with a certain directory would also make it a
safe directory.

Signed-off-by: Matheus Valadares <me@m28.io>
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-04-13 12:42:51 -07:00
Derrick Stolee
e47363e5a8 t0033: add tests for safe.directory
It is difficult to change the ownership on a directory in our test
suite, so insert a new GIT_TEST_ASSUME_DIFFERENT_OWNER environment
variable to trick Git into thinking we are in a differently-owned
directory. This allows us to test that the config is parsed correctly.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-04-13 12:42:49 -07:00
Johannes Schindelin
201b0c7af6 Sync with 2.31.2
* maint-2.31:
  Git 2.31.2
  Git 2.30.3
  setup_git_directory(): add an owner check for the top-level directory
  Add a function to determine whether a path is owned by the current user
2022-03-24 00:31:28 +01:00
Johannes Schindelin
8959555cee setup_git_directory(): add an owner check for the top-level directory
It poses a security risk to search for a git directory outside of the
directories owned by the current user.

For example, it is common e.g. in computer pools of educational
institutes to have a "scratch" space: a mounted disk with plenty of
space that is regularly swiped where any authenticated user can create
a directory to do their work. Merely navigating to such a space with a
Git-enabled `PS1` when there is a maliciously-crafted `/scratch/.git/`
can lead to a compromised account.

The same holds true in multi-user setups running Windows, as `C:\` is
writable to every authenticated user by default.

To plug this vulnerability, we stop Git from accepting top-level
directories owned by someone other than the current user. We avoid
looking at the ownership of each and every directories between the
current and the top-level one (if there are any between) to avoid
introducing a performance bottleneck.

This new default behavior is obviously incompatible with the concept of
shared repositories, where we expect the top-level directory to be owned
by only one of its legitimate users. To re-enable that use case, we add
support for adding exceptions from the new default behavior via the
config setting `safe.directory`.

The `safe.directory` config setting is only respected in the system and
global configs, not from repository configs or via the command-line, and
can have multiple values to allow for multiple shared repositories.

We are particularly careful to provide a helpful message to any user
trying to use a shared repository.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2022-03-21 13:16:26 +01:00
Torsten Bögershausen
c7d0e61016 macOS: precompose startup_info->prefix
The "prefix" was precomposed for macOS in commit 5c327502 (MacOS:
precompose_argv_prefix(), 2021-02-03).

However, this commit forgot to update "startup_info->prefix" after
precomposing.

Move the (possible) precomposition towards the end of
setup_git_directory_gently(), so that precompose_string_if_needed()
can use git_config_get_bool("core.precomposeunicode") correctly.

Keep prefix, startup_info->prefix and GIT_PREFIX_ENVIRONMENT all in sync.

And as a result, the prefix no longer needs to be precomposed in git.c

Reported-by: Dmitry Torilov <d.torilov@gmail.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-05 17:30:36 -07:00
Junio C Hamano
e0ad9574dd Merge branch 'bc/sha-256-part-3'
The final leg of SHA-256 transition.

* bc/sha-256-part-3: (39 commits)
  t: remove test_oid_init in tests
  docs: add documentation for extensions.objectFormat
  ci: run tests with SHA-256
  t: make SHA1 prerequisite depend on default hash
  t: allow testing different hash algorithms via environment
  t: add test_oid option to select hash algorithm
  repository: enable SHA-256 support by default
  setup: add support for reading extensions.objectformat
  bundle: add new version for use with SHA-256
  builtin/verify-pack: implement an --object-format option
  http-fetch: set up git directory before parsing pack hashes
  t0410: mark test with SHA1 prerequisite
  t5308: make test work with SHA-256
  t9700: make hash size independent
  t9500: ensure that algorithm info is preserved in config
  t9350: make hash size independent
  t9301: make hash size independent
  t9300: use $ZERO_OID instead of hard-coded object ID
  t9300: abstract away SHA-1-specific constants
  t8011: make hash size independent
  ...
2020-08-11 18:04:11 -07:00
Junio C Hamano
c28a2d0c12 Merge branch 'jk/reject-newer-extensions-in-v0' into master
With the base fix to 2.27 regresion, any new extensions in a v0
repository would still be silently honored, which is not quite
right.  Instead, complain and die loudly.

* jk/reject-newer-extensions-in-v0:
  verify_repository_format(): complain about new extensions in v0 repo
2020-07-30 13:20:32 -07:00
brian m. carlson
b5b46d7973 setup: add support for reading extensions.objectformat
The transition plan specifies extensions.objectFormat as the indication
that we're using a given hash in a certain repo.  Read this as one of
the extensions we support.  If the user has specified an invalid value,
fail.

Ensure that we reject the extension if the repository format version is
0.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Reviewed-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-30 09:16:49 -07:00
Junio C Hamano
d13b7f2198 Merge branch 'jn/v0-with-extensions-fix' into master
In 2.28-rc0, we corrected a bug that some repository extensions are
honored by mistake even in a version 0 repositories (these
configuration variables in extensions.* namespace were supposed to
have special meaning in repositories whose version numbers are 1 or
higher), but this was a bit too big a change.

* jn/v0-with-extensions-fix:
  repository: allow repository format upgrade with extensions
  Revert "check_repository_format_gently(): refuse extensions for old repositories"
2020-07-16 17:58:42 -07:00
Jeff King
ec91ffca04 verify_repository_format(): complain about new extensions in v0 repo
We made the mistake in the past of respecting extensions.* even when the
repository format version was set to 0. This is bad because forgetting
to bump the repository version means that older versions of Git (which
do not know about our extensions) won't complain. I.e., it's not a
problem in itself, but it means your repository is in a state which does
not give you the protection you think you're getting from older
versions.

For compatibility reasons, we are stuck with that decision for existing
extensions. However, we'd prefer not to extend the damage further. We
can do that by catching any newly-added extensions and complaining about
the repository format.

Note that this is a pretty heavy hammer: we'll refuse to work with the
repository at all. A lesser option would be to ignore (possibly with a
warning) any new extensions. But because of the way the extensions are
handled, that puts the burden on each new extension that is added to
remember to "undo" itself (because they are handled before we know
for sure whether we are in a v1 repo or not, since we don't insist on a
particular ordering of config entries).

So one option would be to rewrite that handling to record any new
extensions (and their values) during the config parse, and then only
after proceed to handle new ones only if we're in a v1 repository. But
I'm not sure if it's worth the trouble:

  - ignoring extensions is likely to end up with broken results anyway
    (e.g., ignoring a proposed objectformat extension means parsing any
    object data is likely to encounter errors)

  - this is a sign that whatever tool wrote the extension field is
    broken. We may be better off notifying immediately and forcefully so
    that such tools don't even appear to work accidentally.

The only downside is that fixing the situation is a little tricky,
because programs like "git config" won't want to work with the
repository. But:

  git config --file=.git/config core.repositoryformatversion 1

should still suffice.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-16 10:39:45 -07:00
Jonathan Nieder
62f2eca606 repository: allow repository format upgrade with extensions
Now that we officially permit repository extensions in repository
format v0, permit upgrading a repository with extensions from v0 to v1
as well.

For example, this means a repository where the user has set
"extensions.preciousObjects" can use "git fetch --filter=blob:none
origin" to upgrade the repository to use v1 and the partial clone
extension.

To avoid mistakes, continue to forbid repository format upgrades in v0
repositories with an unrecognized extension.  This way, a v0 user
using a misspelled extension field gets a chance to correct the
mistake before updating to the less forgiving v1 format.

While we're here, make the error message for failure to upgrade the
repository format a bit shorter, and present it as an error, not a
warning.

Reported-by: Huan Huan Chen <huanhuanchen@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-16 09:36:39 -07:00
Jonathan Nieder
11664196ac Revert "check_repository_format_gently(): refuse extensions for old repositories"
This reverts commit 14c7fa269e.

The core.repositoryFormatVersion field was introduced in ab9cb76f66
(Repository format version check., 2005-11-25), providing a welcome
bit of forward compatibility, thanks to some welcome analysis by
Martin Atukunda.  The semantics are simple: a repository with
core.repositoryFormatVersion set to 0 should be comprehensible by all
Git implementations in active use; and Git implementations should
error out early instead of trying to act on Git repositories with
higher core.repositoryFormatVersion values representing new formats
that they do not understand.

A new repository format did not need to be defined until 00a09d57eb
(introduce "extensions" form of core.repositoryformatversion,
2015-06-23).  This provided a finer-grained extension mechanism for
Git repositories.  In a repository with core.repositoryFormatVersion
set to 1, Git implementations can act on "extensions.*" settings that
modify how a repository is interpreted.  In repository format version
1, unrecognized extensions settings cause Git to error out.

What happens if a user sets an extension setting but forgets to
increase the repository format version to 1?  The extension settings
were still recognized in that case; worse, unrecognized extensions
settings do *not* cause Git to error out.  So combining repository
format version 0 with extensions settings produces in some sense the
worst of both worlds.

To improve that situation, since 14c7fa269e
(check_repository_format_gently(): refuse extensions for old
repositories, 2020-06-05) Git instead ignores extensions in v0 mode.
This way, v0 repositories get the historical (pre-2015) behavior and
maintain compatibility with Git implementations that do not know about
the v1 format.  Unfortunately, users had been using this sort of
configuration and this behavior change came to many as a surprise:

- users of "git config --worktree" that had followed its advice
  to enable extensions.worktreeConfig (without also increasing the
  repository format version) would find their worktree configuration
  no longer taking effect

- tools such as copybara[*] that had set extensions.partialClone in
  existing repositories (without also increasing the repository format
  version) would find that setting no longer taking effect

The behavior introduced in 14c7fa269e might be a good behavior if we
were traveling back in time to 2015, but we're far too late.  For some
reason I thought that it was what had been originally implemented and
that it had regressed.  Apologies for not doing my research when
14c7fa269e was under development.

Let's return to the behavior we've had since 2015: always act on
extensions.* settings, regardless of repository format version.  While
we're here, include some tests to describe the effect on the "upgrade
repository version" code path.

[*] ca76c0b1e1

Reported-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-16 09:36:37 -07:00
Junio C Hamano
12210859da Merge branch 'bc/sha-256-part-2'
SHA-256 migration work continues.

* bc/sha-256-part-2: (44 commits)
  remote-testgit: adapt for object-format
  bundle: detect hash algorithm when reading refs
  t5300: pass --object-format to git index-pack
  t5704: send object-format capability with SHA-256
  t5703: use object-format serve option
  t5702: offer an object-format capability in the test
  t/helper: initialize the repository for test-sha1-array
  remote-curl: avoid truncating refs with ls-remote
  t1050: pass algorithm to index-pack when outside repo
  builtin/index-pack: add option to specify hash algorithm
  remote-curl: detect algorithm for dumb HTTP by size
  builtin/ls-remote: initialize repository based on fetch
  t5500: make hash independent
  serve: advertise object-format capability for protocol v2
  connect: parse v2 refs with correct hash algorithm
  connect: pass full packet reader when parsing v2 refs
  Documentation/technical: document object-format for protocol v2
  t1302: expect repo format version 1 for SHA-256
  builtin/show-index: provide options to determine hash algo
  t5302: modernize test formatting
  ...
2020-07-06 22:09:13 -07:00
Xin Li
14c7fa269e check_repository_format_gently(): refuse extensions for old repositories
Previously, extensions were recognized regardless of repository format
version.  If the user sets an undefined "extensions" value on a
repository of version 0 and that value is used by a future git version,
they might get an undesired result.

Because all extensions now also upgrade repository versions, tightening
the check would help avoid this for future extensions.

Signed-off-by: Xin Li <delphij@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-06-05 10:13:30 -07:00
Xin Li
16af5f1abb repository: add a helper function to perform repository format upgrade
In version 1 of repository format, "extensions" gained special meaning
and it is safer to avoid upgrading when there are pre-existing
extensions.

Make list-objects-filter to use the helper function instead of setting
repository version directly as a prerequisite of exposing the upgrade
capability.

Signed-off-by: Xin Li <delphij@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-06-05 10:13:30 -07:00
brian m. carlson
d553acebee setup: set the_repository's hash algo when checking format
When we're checking the repository's format, set the hash algorithm at
the same time.  This ensures that we perform a suitable initialization
early enough to avoid confusing any parts of the code.  If we defer
until later, we can end up with portions of the code which are confused
about the hash algorithm, resulting in segfaults when working with
SHA-256 repositories.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-05-27 10:07:06 -07:00
Junio C Hamano
f8cb64e3d4 Merge branch 'bc/sha-256-part-1-of-4'
SHA-256 transition continues.

* bc/sha-256-part-1-of-4: (22 commits)
  fast-import: add options for rewriting submodules
  fast-import: add a generic function to iterate over marks
  fast-import: make find_marks work on any mark set
  fast-import: add helper function for inserting mark object entries
  fast-import: permit reading multiple marks files
  commit: use expected signature header for SHA-256
  worktree: allow repository version 1
  init-db: move writing repo version into a function
  builtin/init-db: add environment variable for new repo hash
  builtin/init-db: allow specifying hash algorithm on command line
  setup: allow check_repository_format to read repository format
  t/helper: make repository tests hash independent
  t/helper: initialize repository if necessary
  t/helper/test-dump-split-index: initialize git repository
  t6300: make hash algorithm independent
  t6300: abstract away SHA-1-specific constants
  t: use hash-specific lookup tables to define test constants
  repository: require a build flag to use SHA-256
  hex: add functions to parse hex object IDs in any algorithm
  hex: introduce parsing variants taking hash algorithms
  ...
2020-03-26 17:11:20 -07:00
Junio C Hamano
4d0e8996ec Merge branch 'am/real-path-fix'
The real_path() convenience function can easily be misused; with a
bit of code refactoring in the callers' side, its use has been
eliminated.

* am/real-path-fix:
  get_superproject_working_tree(): return strbuf
  real_path_if_valid(): remove unsafe API
  real_path: remove unsafe API
  set_git_dir: fix crash when used with real_path()
2020-03-25 13:57:43 -07:00
Junio C Hamano
e96327c947 Merge branch 'es/outside-repo-errmsg-hints'
An earlier update to show the location of working tree in the error
message did not consider the possibility that a git command may be
run in a bare repository, which has been corrected.

* es/outside-repo-errmsg-hints:
  prefix_path: show gitdir if worktree unavailable
2020-03-16 12:43:29 -07:00
Emily Shaffer
5c20398699 prefix_path: show gitdir if worktree unavailable
If there is no worktree at present, we can still hint the user about
Git's current directory by showing them the absolute path to the Git
directory. Even though the Git directory doesn't make it as easy to
locate the worktree in question, it can still help a user figure out
what's going on while developing a script.

This fixes a segmentation fault introduced in e0020b2f
("prefix_path: show gitdir when arg is outside repo", 2020-02-14).

Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
[jc: added minimum tests, with help from Szeder Gábor]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-15 09:35:46 -07:00
Alexandr Miloslavskiy
4530a85b4c real_path_if_valid(): remove unsafe API
This commit continues the work started with previous commit.

Signed-off-by: Alexandr Miloslavskiy <alexandr.miloslavskiy@syntevo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-10 11:41:40 -07:00
Alexandr Miloslavskiy
3d7747e318 real_path: remove unsafe API
Returning a shared buffer invites very subtle bugs due to reentrancy or
multi-threading, as demonstrated by the previous patch.

There was an unfinished effort to abolish this [1].

Let's finally rid of `real_path()`, using `strbuf_realpath()` instead.

This patch uses a local `strbuf` for most places where `real_path()` was
previously called.

However, two places return the value of `real_path()` to the caller. For
them, a `static` local `strbuf` was added, effectively pushing the
problem one level higher:
    read_gitfile_gently()
    get_superproject_working_tree()

[1] https://lore.kernel.org/git/1480964316-99305-1-git-send-email-bmwill@google.com/

Signed-off-by: Alexandr Miloslavskiy <alexandr.miloslavskiy@syntevo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-10 11:41:40 -07:00
Alexandr Miloslavskiy
0915a5b4cd set_git_dir: fix crash when used with real_path()
`real_path()` returns result from a shared buffer, inviting subtle
reentrance bugs. One of these bugs occur when invoked this way:
    set_git_dir(real_path(git_dir))

In this case, `real_path()` has reentrance:
    real_path
    read_gitfile_gently
    repo_set_gitdir
    setup_git_env
    set_git_dir_1
    set_git_dir

Later, `set_git_dir()` uses its now-dead parameter:
    !is_absolute_path(path)

Fix this by using a dedicated `strbuf` to hold `strbuf_realpath()`.

Signed-off-by: Alexandr Miloslavskiy <alexandr.miloslavskiy@syntevo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-06 14:45:51 -08:00
brian m. carlson
cfe3917c85 setup: allow check_repository_format to read repository format
In some cases, we will want to not only check the repository format, but
extract the information that we've gained.  To do so, allow
check_repository_format to take a pointer to struct repository_format.
Allow passing NULL for this argument if we're not interested in the
information, and pass NULL for all existing callers.  A future patch
will make use of this information.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-24 09:33:27 -08:00
Junio C Hamano
f97741f6e9 Merge branch 'es/outside-repo-errmsg-hints'
Error message clarification.

* es/outside-repo-errmsg-hints:
  prefix_path: show gitdir when arg is outside repo
2020-02-17 13:22:19 -08:00
Emily Shaffer
e0020b2f82 prefix_path: show gitdir when arg is outside repo
When developing a script, it can be painful to understand why Git thinks
something is outside the current repo, if the current repo isn't what
the user thinks it is. Since this can be tricky to diagnose, especially
in cases like submodules or nested worktrees, let's give the user a hint
about which repository is offended about that path.

Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
Acked-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-16 15:32:59 -08:00
Jeff King
39e21c6ef5 verify_filename(): handle backslashes in "wildcards are pathspecs" rule
Commit 28fcc0b71a (pathspec: avoid the need of "--" when wildcard is
used, 2015-05-02) allowed:

  git rev-parse '*.c'

without the double-dash. But the rule it uses to check for wildcards
actually looks for any glob special. This is overly liberal, as it means
that a pattern that doesn't actually do any wildcard matching, like
"a\b", will be considered a pathspec.

If you do have such a file on disk, that's presumably what you wanted.
But if you don't, the results are confusing: rather than say "there's no
such path a\b", we'll quietly accept it as a pathspec which very likely
matches nothing (or at least not what you intended). Likewise, looking
for path "a\*b" doesn't expand the search at all; it would only find a
single entry, "a*b".

This commit switches the rule to trigger only when glob metacharacters
would expand the search, meaning both of those cases will now report an
error (you can still disambiguate using "--", of course; we're just
tightening the DWIM heuristic).

Note that we didn't test the original feature in 28fcc0b71a at all. So
this patch not only tests for these corner cases, but also adds a
regression test for the existing behavior.

Reported-by: David Burström <davidburstrom@spotify.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-27 10:46:35 -08:00
Junio C Hamano
b57a88a5f1 Merge branch 'js/gitdir-at-unc-root'
On Windows, the root level of UNC share is now allowed to be used
just like any other directory.

* js/gitdir-at-unc-root:
  setup_git_directory(): handle UNC root paths correctly
  Fix .git/ discovery at the root of UNC shares
  setup_git_directory(): handle UNC paths correctly
2019-09-30 13:19:26 +09:00
Johannes Schindelin
5cf7b3b1ac setup_git_directory(): handle UNC root paths correctly
When working in the root directory of a file share (this is only
possible in Git Bash and Powershell, but not in CMD), the current
directory is reported without a trailing slash.

This is different from Unix and standard Windows directories: both / and
C:\ are reported with a trailing slash as current directories.

If a Git worktree is located there, Git is not quite prepared for that:
while it does manage to find the .git directory/file, it returns as
length of the top-level directory's path *one more* than the length of
the current directory, and setup_git_directory_gently() would then
return an undefined string as prefix.

In practice, this undefined string usually points to NUL bytes, and does
not cause much harm. Under rare circumstances that are really involved
to reproduce (and not reliably so), the reported prefix could be a
suffix string of Git's exec path, though.

A careful analysis determined that this bug is unlikely to be
exploitable, therefore we mark this as a regular bug fix.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-08-26 10:03:41 -07:00
Johannes Schindelin
e2683d51d9 Fix .git/ discovery at the root of UNC shares
A very common assumption in Git's source code base is that
offset_1st_component() returns either 0 for relative paths, or 1 for
absolute paths that start with a slash. In other words, the return value
is either 0 or points just after the dir separator.

This assumption is not fulfilled when calling offset_1st_component()
e.g. on UNC paths on Windows, e.g. "//my-server/my-share". In this case,
offset_1st_component() returns the length of the entire string (which is
correct, because stripping the last "component" would not result in a
valid directory), yet the return value still does not point just after a
dir separator.

This assumption is most prominently seen in the
setup_git_directory_gently_1() function, where we want to append a
".git" component and simply assume that there is already a dir
separator. In the UNC example given above, this assumption is incorrect.

As a consequence, Git will fail to handle a worktree at the top of a UNC
share correctly.

Let's fix this by adding a dir separator specifically for that case: we
found that there is no first component in the path and it does not end
in a dir separator? Then add it.

This fixes https://github.com/git-for-windows/git/issues/1320

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-08-26 10:03:41 -07:00
Johannes Schindelin
d17f2124a7 setup_git_directory(): handle UNC paths correctly
The first offset in a UNC path is not the host name, but the folder name after that.

This fixes https://github.com/git-for-windows/git/issues/1181

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-08-26 10:03:41 -07:00
Christian Couder
60b7a92d84 Move repository_format_partial_clone to promisor-remote.c
Now that we have has_promisor_remote() and can use many
promisor remotes, let's hide repository_format_partial_clone
as a static in promisor-remote.c to avoid it being use
for anything other than managing backward compatibility.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-25 14:05:38 -07:00
Nguyễn Thái Ngọc Duy
e270f42c4d sha1-name.c: remove the_repo from maybe_die_on_misspelt_object_name
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-04-16 18:56:53 +09:00
Junio C Hamano
6b5688b760 Merge branch 'ma/clear-repository-format'
The setup code has been cleaned up to avoid leaks around the
repository_format structure.

* ma/clear-repository-format:
  setup: fix memory leaks with `struct repository_format`
  setup: free old value before setting `work_tree`
2019-03-20 15:16:07 +09:00
Martin Ågren
e8805af1c3 setup: fix memory leaks with struct repository_format
After we set up a `struct repository_format`, it owns various pieces of
allocated memory. We then either use those members, because we decide we
want to use the "candidate" repository format, or we discard the
candidate / scratch space. In the first case, we transfer ownership of
the memory to a few global variables. In the latter case, we just
silently drop the struct and end up leaking memory.

Introduce an initialization macro `REPOSITORY_FORMAT_INIT` and a
function `clear_repository_format()`, to be used on each side of
`read_repository_format()`. To have a clear and simple memory ownership,
let all users of `struct repository_format` duplicate the strings that
they take from it, rather than stealing the pointers.

Call `clear_...()` at the start of `read_...()` instead of just zeroing
the struct, since we sometimes enter the function multiple times. Thus,
it is important to initialize the struct before calling `read_...()`, so
document that. It's also important because we might not even call
`read_...()` before we call `clear_...()`, see, e.g., builtin/init-db.c.

Teach `read_...()` to clear the struct on error, so that it is reset to
a safe state, and document this. (In `setup_git_directory_gently()`, we
look at `repo_fmt.hash_algo` even if `repo_fmt.version` is -1, which we
weren't actually supposed to do per the API. After this commit, that's
ok.)

We inherit the existing code's combining "error" and "no version found".
Both are signalled through `version == -1` and now both cause us to
clear any partial configuration we have picked up. For "extensions.*",
that's fine, since they require a positive version number. For
"core.bare" and "core.worktree", we're already verifying that we have a
non-negative version number before using them.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-03-01 08:52:00 +09:00
Junio C Hamano
ff09c9e5ba Merge branch 'js/abspath-part-inside-repo'
On a case-insensitive filesystem, we failed to compare the part of
the path that is above the worktree directory in an absolute
pathname, which has been corrected.

* js/abspath-part-inside-repo:
  abspath_part_inside_repo: respect core.ignoreCase
2019-02-05 14:26:15 -08:00
Martin Ågren
13019979b8 setup: free old value before setting work_tree
Before assigning to `data->work_tree` in `read_worktree_config()`, free
any value we might already have picked up, so that we do not leak it.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-01-23 13:15:58 -08:00
Johannes Schindelin
d8727b3687 abspath_part_inside_repo: respect core.ignoreCase
If the file system is case-insensitive, we really must be careful to
ignore differences in case only.

This fixes https://github.com/git-for-windows/git/issues/735

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-01-18 09:53:06 -08:00
Erin Dahlgren
07098b81a4 Simplify handling of setup_git_directory_gently() failure cases.
setup_git_directory_gently() expects two types of failures to
discover a git directory (e.g. .git/):

  - GIT_DIR_HIT_CEILING: could not find a git directory in any
	parent directories of the cwd.
  - GIT_DIR_HIT_MOUNT_POINT: could not find a git directory in
	any parent directories up to the mount point of the cwd.

Both cases are handled in a similar way, but there are misleading
and unimportant differences. In both cases, setup_git_directory_gently()
should:

  - Die if we are not in a git repository. Otherwise:
  - Set nongit_ok = 1, indicating that we are not in a git repository
	but this is ok.
  - Call strbuf_release() on any non-static struct strbufs that we
	allocated.

Before this change are two misleading additional behaviors:

  - GIT_DIR_HIT_CEILING: setup_nongit() changes to the cwd for no
	apparent reason. We never had the chance to change directories
	up to this point so chdir(current cwd) is pointless.
  - GIT_DIR_HIT_MOUNT_POINT: strbuf_release() frees the buffer
	of a static struct strbuf (cwd). This is unnecessary because the
	struct is static so its buffer is always reachable. This is also
	misleading because nowhere else in the function is this buffer
	released.

This change eliminates these two misleading additional behaviors and
deletes setup_nogit() because the code is clearer without it. The
result is that we can see clearly that GIT_DIR_HIT_CEILING and
GIT_DIR_HIT_MOUNT_POINT lead to the same behavior (ignoring the
different help messages).

During review, this change was amended to additionally include:

  - Neither GIT_DIR_HIT_CEILING nor GIT_DIR_HIT_MOUNT_POINT may
	return early from setup_git_directory_gently() before the
	GIT_PREFIX environment variable is reset. Change both cases to
	break instead of return. See GIT_PREFIX below for more details.

  - GIT_DIR_NONE: setup_git_directory_gently_1() never returns this
	value, but if it ever did, setup_git_directory_gently() would
	incorrectly record that it had found a repository. Explicitly
	BUG on this case because it is underspecified.

  - GIT_PREFIX: this environment variable must always match the
	value of startup_info->prefix and the prefix returned from
	setup_git_directory_gently(). Make how we handle this slightly
	more repetitive but also more clear.

  - setup_git_env() and repo_set_hash_algo(): Add comments showing
	that only GIT_DIR_EXPLICIT, GIT_DIR_DISCOVERED, and GIT_DIR_BARE
	will cause setup_git_directory_gently() to call these setup
	functions. This was obvious (but partly incorrect) before this
	change when GIT_DIR_HIT_MOUNT_POINT returned early from
	setup_git_directory_gently().

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-01-03 10:41:39 -08:00
Nguyễn Thái Ngọc Duy
58b284a2e9 worktree: add per-worktree config files
A new repo extension is added, worktreeConfig. When it is present:

 - Repository config reading by default includes $GIT_DIR/config _and_
   $GIT_DIR/config.worktree. "config" file remains shared in multiple
   worktree setup.

 - The special treatment for core.bare and core.worktree, to stay
   effective only in main worktree, is gone. These config settings are
   supposed to be in config.worktree.

This extension is most useful in multiple worktree setup because you
now have an option to store per-worktree config (which is either
.git/config.worktree for main worktree, or
.git/worktrees/xx/config.worktree for linked ones).

This extension can be used in single worktree mode, even though it's
pretty much useless (but this can happen after you remove all linked
worktrees and move back to single worktree).

"git config" reads from both "config" and "config.worktree" by default
(i.e. without either --user, --file...) when this extension is
present. Default writes still go to "config", not "config.worktree". A
new option --worktree is added for that (*).

Since a new repo extension is introduced, existing git binaries should
refuse to access to the repo (both from main and linked worktrees). So
they will not misread the config file (i.e. skip the config.worktree
part). They may still accidentally write to the config file anyway if
they use with "git config --file <path>".

This design places a bet on the assumption that the majority of config
variables are shared so it is the default mode. A safer move would be
default writes go to per-worktree file, so that accidental changes are
isolated.

(*) "git config --worktree" points back to "config" file when this
    extension is not present and there is only one worktree so that it
    works in any both single and multiple worktree setups.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-22 13:17:04 +09:00
Johannes Schindelin
033abf97fc Replace all die("BUG: ...") calls by BUG() ones
In d8193743e0 (usage.c: add BUG() function, 2017-05-12), a new macro
was introduced to use for reporting bugs instead of die(). It was then
subsequently used to convert one single caller in 588a538ae5
(setup_git_env: convert die("BUG") to BUG(), 2017-05-12).

The cover letter of the patch series containing this patch
(cf 20170513032414.mfrwabt4hovujde2@sigill.intra.peff.net) is not
terribly clear why only one call site was converted, or what the plan
is for other, similar calls to die() to report bugs.

Let's just convert all remaining ones in one fell swoop.

This trick was performed by this invocation:

	sed -i 's/die("BUG: /BUG("/g' $(git grep -l 'die("BUG' \*.c)

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-06 19:06:13 +09:00
Junio C Hamano
ff6eb825f0 Merge branch 'jk/relative-directory-fix'
Some codepaths, including the refs API, get and keep relative
paths, that go out of sync when the process does chdir(2).  The
chdir-notify API is introduced to let these codepaths adjust these
cached paths to the new current directory.

* jk/relative-directory-fix:
  refs: use chdir_notify to update cached relative paths
  set_work_tree: use chdir_notify
  add chdir-notify API
  trace.c: export trace_setup_key
  set_git_dir: die when setenv() fails
2018-04-25 13:28:52 +09:00
Junio C Hamano
0873c393c7 Merge branch 'nd/remove-ignore-env-field'
Code clean-up for the "repository" abstraction.

* nd/remove-ignore-env-field:
  repository.h: add comment and clarify repo_set_gitdir
  repository: delete ignore_env member
  sha1_file.c: move delayed getenv(altdb) back to setup_git_env()
  repository.c: delete dead functions
  repository.c: move env-related setup code back to environment.c
  repository: initialize the_repository in main()
2018-04-10 16:28:20 +09:00
Jeff King
8500e0de3f set_work_tree: use chdir_notify
When we change to the top of the working tree, we manually
re-adjust $GIT_DIR and call set_git_dir() again, in order to
update any relative git-dir we'd compute earlier.

Instead of the work-tree code having to know to call the
git-dir code, let's use the new chdir_notify interface.
There are two spots that need updating, with a few
subtleties in each:

  1. the set_git_dir() code needs to chdir_notify_register()
     so it can be told when to update its path.

     Technically we could push this down into repo_set_gitdir(),
     so that even repository structs besides the_repository
     could benefit from this. But that opens up a lot of
     complications:

      - we'd still need to touch set_git_dir(), because it
        does some other setup (like setting $GIT_DIR in the
        environment)

      - submodules using other repository structs get
        cleaned up, which means we'd need to remove them
        from the chdir_notify list

      - it's unlikely to fix any bugs, since we shouldn't
        generally chdir() in the middle of working on a
        submodule

  2. setup_work_tree now needs to call chdir_notify(), and
     can lose its manual set_git_dir() call.

     Note that at first glance it looks like this undoes the
     absolute-to-relative optimization added by 044bbbcb63
     (Make git_dir a path relative to work_tree in
     setup_work_tree(), 2008-06-19). But for the most part
     that optimization was just _undoing_ the
     relative-to-absolute conversion which the function was
     doing earlier (and which is now gone).

     It is true that if you already have an absolute git_dir
     that the setup_work_tree() function will no longer make
     it relative as a side effect. But:

       - we generally do have relative git-dir's due to the
         way the discovery code works

       - if we really care about making git-dir's relative
         when possible, then we should be relativizing them
         earlier (e.g., when we see an absolute $GIT_DIR we
         could turn it relative, whether we are going to
         chdir into a worktree or not). That would cover all
         cases, including ones that 044bbbcb63 did not.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-03-30 12:49:57 -07:00
Nguyễn Thái Ngọc Duy
357a03ebe9 repository.c: move env-related setup code back to environment.c
It does not make sense that generic repository code contains handling
of environment variables, which are specific for the main repository
only. Refactor repo_set_gitdir() function to take $GIT_DIR and
optionally _all_ other customizable paths. These optional paths can be
NULL and will be calculated according to the default directory layout.

Note that some dead functions are left behind to reduce diff
noise. They will be deleted in the next patch.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-03-05 11:14:03 -08:00
Junio C Hamano
d4053966ea Merge branch 'as/ll-i18n'
Some messages in low level start-up codepath have been i18n-ized.

* as/ll-i18n:
  Mark messages for translations
2018-02-27 10:33:58 -08:00