Commit graph

20 commits

Author SHA1 Message Date
Glen Choo 4e33535ea9 clone: error specifically with --local and symlinked objects
6f054f9fb3 (builtin/clone.c: disallow --local clones with
symlinks, 2022-07-28) gives a good error message when "git clone
--local" fails when the repo to clone has symlinks in
"$GIT_DIR/objects". In bffc762f87 (dir-iterator: prevent top-level
symlinks without FOLLOW_SYMLINKS, 2023-01-24), we later extended this
restriction to the case where "$GIT_DIR/objects" is itself a symlink,
but we didn't update the error message then - bffc762f87's tests show
that we print a generic "failed to start iterator over" message.

This is exacerbated by the fact that Documentation/git-clone.txt
mentions neither restriction, so users are left wondering if this is
intentional behavior or not.

Fix this by adding a check to builtin/clone.c: when doing a local clone,
perform an extra check to see if "$GIT_DIR/objects" is a symlink, and if
so, assume that that was the reason for the failure and report the
relevant information. Ideally, dir_iterator_begin() would tell us that
the real failure reason is the presence of the symlink, but (as far as I
can tell) there isn't an appropriate errno value for that.

Also, update Documentation/git-clone.txt to reflect that this
restriction exists.

Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-11 08:46:09 -07:00
Junio C Hamano 72972ea0b9 Merge branch 'ab/various-leak-fixes'
Leak fixes.

* ab/various-leak-fixes:
  push: free_refs() the "local_refs" in set_refspecs()
  push: refactor refspec_append_mapped() for subsequent leak-fix
  receive-pack: release the linked "struct command *" list
  grep API: plug memory leaks by freeing "header_list"
  grep.c: refactor free_grep_patterns()
  builtin/merge.c: free "&buf" on "Your local changes..." error
  builtin/merge.c: use fixed strings, not "strbuf", fix leak
  show-branch: free() allocated "head" before return
  commit-graph: fix a parse_options_concat() leak
  http-backend.c: fix cmd_main() memory leak, refactor reg{exec,free}()
  http-backend.c: fix "dir" and "cmd_arg" leaks in cmd_main()
  worktree: fix a trivial leak in prune_worktrees()
  repack: fix leaks on error with "goto cleanup"
  name-rev: don't xstrdup() an already dup'd string
  various: add missing clear_pathspec(), fix leaks
  clone: use free() instead of UNLEAK()
  commit-graph: use free_commit_graph() instead of UNLEAK()
  bundle.c: don't leak the "args" in the "struct child_process"
  tests: mark tests as passing with SANITIZE=leak
2023-02-22 14:55:45 -08:00
Ævar Arnfjörð Bjarmason b2e5d75d17 tests: mark tests as passing with SANITIZE=leak
When the "ab/various-leak-fixes" topic was merged in [1] only t6021
would fail if the tests were run in the
"GIT_TEST_PASSING_SANITIZE_LEAK=check" mode, i.e. to check whether we
marked all leak-free tests with "TEST_PASSES_SANITIZE_LEAK=true".

Since then we've had various tests starting to pass under
SANITIZE=leak. Let's mark those as passing, this is when they started
to pass, narrowed down with "git bisect":

- t5317-pack-objects-filter-objects.sh: In
  faebba436e (list-objects-filter: plug pattern_list leak, 2022-12-01).

- t3210-pack-refs.sh, t5613-info-alternate.sh,
  t7403-submodule-sync.sh: In 189e97bc4b (diff: remove parseopts member
  from struct diff_options, 2022-12-01).

- t1408-packed-refs.sh: In ab91f6b7c4 (Merge branch
  'rs/diff-parseopts', 2022-12-19).

- t0023-crlf-am.sh, t4152-am-subjects.sh, t4254-am-corrupt.sh,
  t4256-am-format-flowed.sh, t4257-am-interactive.sh,
  t5403-post-checkout-hook.sh: In a658e881c1 (am: don't pass strvec to
  apply_parse_options(), 2022-12-13)

- t1301-shared-repo.sh, t1302-repo-version.sh: In b07a819c05 (reflog:
  clear leftovers in reflog_expiry_cleanup(), 2022-12-13).

- t1304-default-acl.sh, t1410-reflog.sh,
  t5330-no-lazy-fetch-with-commit-graph.sh, t5502-quickfetch.sh,
  t5604-clone-reference.sh, t6014-rev-list-all.sh,
  t7701-repack-unpack-unreachable.sh: In b0c61be320 (Merge branch
  'rs/reflog-expiry-cleanup', 2022-12-26)

- t3800-mktag.sh, t5302-pack-index.sh, t5306-pack-nobase.sh,
  t5573-pull-verify-signatures.sh, t7612-merge-verify-signatures.sh: In
  69bbbe484b (hash-object: use fsck for object checks, 2023-01-18).

- t1451-fsck-buffer.sh: In 8e4309038f (fsck: do not assume
  NUL-termination of buffers, 2023-01-19).

- t6501-freshen-objects.sh: In abf2bb895b (Merge branch
  'jk/hash-object-fsck', 2023-01-30)

1. 9ea1378d04 (Merge branch 'ab/various-leak-fixes', 2022-12-14)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-06 15:34:36 -08:00
Johannes Schindelin 87248c5933 Sync with 2.32.6
* maint-2.32:
  Git 2.32.6
  Git 2.31.7
  Git 2.30.8
  apply: fix writing behind newly created symbolic links
  dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS
  clone: delay picking a transport until after get_repo_path()
  t5619: demonstrate clone_local() with ambiguous transport
2023-02-06 09:25:56 +01:00
Johannes Schindelin e14d6b8408 Sync with 2.30.8
* maint-2.30:
  Git 2.30.8
  apply: fix writing behind newly created symbolic links
  dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS
  clone: delay picking a transport until after get_repo_path()
  t5619: demonstrate clone_local() with ambiguous transport
2023-02-06 09:24:06 +01:00
Taylor Blau bffc762f87 dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS
When using the dir_iterator API, we first stat(2) the base path, and
then use that as a starting point to enumerate the directory's contents.

If the directory contains symbolic links, we will immediately die() upon
encountering them without the `FOLLOW_SYMLINKS` flag. The same is not
true when resolving the top-level directory, though.

As explained in a previous commit, this oversight in 6f054f9fb3
(builtin/clone.c: disallow `--local` clones with symlinks, 2022-07-28)
can be used as an attack vector to include arbitrary files on a victim's
filesystem from outside of the repository.

Prevent resolving top-level symlinks unless the FOLLOW_SYMLINKS flag is
given, which will cause clones of a repository with a symlink'd
"$GIT_DIR/objects" directory to fail.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-24 16:52:16 -08:00
Taylor Blau 3957f3c84e Sync with 2.32.4
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-10-06 17:42:02 -04:00
Taylor Blau 122512967e Sync with 2.30.6
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-10-06 17:39:15 -04:00
Taylor Blau 6f054f9fb3 builtin/clone.c: disallow --local clones with symlinks
When cloning a repository with `--local`, Git relies on either making a
hardlink or copy to every file in the "objects" directory of the source
repository. This is done through the callpath `cmd_clone()` ->
`clone_local()` -> `copy_or_link_directory()`.

The way this optimization works is by enumerating every file and
directory recursively in the source repository's `$GIT_DIR/objects`
directory, and then either making a copy or hardlink of each file. The
only exception to this rule is when copying the "alternates" file, in
which case paths are rewritten to be absolute before writing a new
"alternates" file in the destination repo.

One quirk of this implementation is that it dereferences symlinks when
cloning. This behavior was most recently modified in 36596fd2df (clone:
better handle symlinked files at .git/objects/, 2019-07-10), which
attempted to support `--local` clones of repositories with symlinks in
their objects directory in a platform-independent way.

Unfortunately, this behavior of dereferencing symlinks (that is,
creating a hardlink or copy of the source's link target in the
destination repository) can be used as a component in attacking a
victim by inadvertently exposing the contents of file stored outside of
the repository.

Take, for example, a repository that stores a Dockerfile and is used to
build Docker images. When building an image, Docker copies the directory
contents into the VM, and then instructs the VM to execute the
Dockerfile at the root of the copied directory. This protects against
directory traversal attacks by copying symbolic links as-is without
dereferencing them.

That is, if a user has a symlink pointing at their private key material
(where the symlink is present in the same directory as the Dockerfile,
but the key itself is present outside of that directory), the key is
unreadable to a Docker image, since the link will appear broken from the
container's point of view.

This behavior enables an attack whereby a victim is convinced to clone a
repository containing an embedded submodule (with a URL like
"file:///proc/self/cwd/path/to/submodule") which has a symlink pointing
at a path containing sensitive information on the victim's machine. If a
user is tricked into doing this, the contents at the destination of
those symbolic links are exposed to the Docker image at runtime.

One approach to preventing this behavior is to recreate symlinks in the
destination repository. But this is problematic, since symlinking the
objects directory are not well-supported. (One potential problem is that
when sharing, e.g. a "pack" directory via symlinks, different writers
performing garbage collection may consider different sets of objects to
be reachable, enabling a situation whereby garbage collecting one
repository may remove reachable objects in another repository).

Instead, prohibit the local clone optimization when any symlinks are
present in the `$GIT_DIR/objects` directory of the source repository.
Users may clone the repository again by prepending the "file://" scheme
to their clone URL, or by adding the `--no-local` option to their `git
clone` invocation.

The directory iterator used by `copy_or_link_directory()` must no longer
dereference symlinks (i.e., it *must* call `lstat()` instead of `stat()`
in order to discover whether or not there are symlinks present). This has
no bearing on the overall behavior, since we will immediately `die()` on
encounter a symlink.

Note that t5604.33 suggests that we do support local clones with
symbolic links in the source repository's objects directory, but this
was likely unintentional, or at least did not take into consideration
the problem with sharing parts of the objects directory with symbolic
links at the time. Update this test to reflect which options are and
aren't supported.

Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-10-01 00:23:38 -04:00
Elijah Newren 031e2f7ae1 pull: abort by default when fast-forwarding is not possible
We have for some time shown a long warning when the user does not
specify how to reconcile divergent branches with git pull.  Make it an
error now.

Initial-patch-by: Alex Henrie <alexhenrie24@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-07-22 11:54:29 -07:00
Taylor Blau 35a8a3547a t: prepare for GIT_TEST_WRITE_REV_INDEX
In the next patch, we'll add support for unconditionally enabling the
'pack.writeReverseIndex' setting with a new GIT_TEST_WRITE_REV_INDEX
environment variable.

This causes a little bit of fallout with tests that, for example,
compare the list of files in the pack directory being unprepared to see
.rev files in its output.

Those locations can be cleaned up to look for specific file extensions,
rather than take everything in the pack directory (for instance) and
then grep out unwanted items.

Once the pack.writeReverseIndex option has been thoroughly
tested, we will default it to 'true', removing GIT_TEST_WRITE_REV_INDEX,
and making it possible to revert this patch.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-01-25 18:32:44 -08:00
Johannes Schindelin 95cf2c0187 t5[6-9]*: adjust the references to the default branch name "main"
This trick was performed via

	$ (cd t &&
	   sed -i -e 's/master/main/g' -e 's/MASTER/MAIN/g' \
		-e 's/Master/Main/g' -- t5[6-9]*.sh)

This allows us to define `GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main`
for those tests.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-11-19 15:44:18 -08:00
Johannes Schindelin 334afbc76f tests: mark tests relying on the current default for init.defaultBranch
In addition to the manual adjustment to let the `linux-gcc` CI job run
the test suite with `master` and then with `main`, this patch makes sure
that GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME is set in all test scripts
that currently rely on the initial branch name being `master by default.

To determine which test scripts to mark up, the first step was to
force-set the default branch name to `master` in

- all test scripts that contain the keyword `master`,

- t4211, which expects `t/t4211/history.export` with a hard-coded ref to
  initialize the default branch,

- t5560 because it sources `t/t556x_common` which uses `master`,

- t8002 and t8012 because both source `t/annotate-tests.sh` which also
  uses `master`)

This trick was performed by this command:

	$ sed -i '/^ *\. \.\/\(test-lib\|lib-\(bash\|cvs\|git-svn\)\|gitweb-lib\)\.sh$/i\
	GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=master\
	export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME\
	' $(git grep -l master t/t[0-9]*.sh) \
	t/t4211*.sh t/t5560*.sh t/t8002*.sh t/t8012*.sh

After that, careful, manual inspection revealed that some of the test
scripts containing the needle `master` do not actually rely on a
specific default branch name: either they mention `master` only in a
comment, or they initialize that branch specificially, or they do not
actually refer to the current default branch. Therefore, the
aforementioned modification was undone in those test scripts thusly:

	$ git checkout HEAD -- \
		t/t0027-auto-crlf.sh t/t0060-path-utils.sh \
		t/t1011-read-tree-sparse-checkout.sh \
		t/t1305-config-include.sh t/t1309-early-config.sh \
		t/t1402-check-ref-format.sh t/t1450-fsck.sh \
		t/t2024-checkout-dwim.sh \
		t/t2106-update-index-assume-unchanged.sh \
		t/t3040-subprojects-basic.sh t/t3301-notes.sh \
		t/t3308-notes-merge.sh t/t3423-rebase-reword.sh \
		t/t3436-rebase-more-options.sh \
		t/t4015-diff-whitespace.sh t/t4257-am-interactive.sh \
		t/t5323-pack-redundant.sh t/t5401-update-hooks.sh \
		t/t5511-refspec.sh t/t5526-fetch-submodules.sh \
		t/t5529-push-errors.sh t/t5530-upload-pack-error.sh \
		t/t5548-push-porcelain.sh \
		t/t5552-skipping-fetch-negotiator.sh \
		t/t5572-pull-submodule.sh t/t5608-clone-2gb.sh \
		t/t5614-clone-submodules-shallow.sh \
		t/t7508-status.sh t/t7606-merge-custom.sh \
		t/t9302-fast-import-unpack-limit.sh

We excluded one set of test scripts in these commands, though: the range
of `git p4` tests. The reason? `git p4` stores the (foreign) remote
branch in the branch called `p4/master`, which is obviously not the
default branch. Manual analysis revealed that only five of these tests
actually require a specific default branch name to pass; They were
modified thusly:

	$ sed -i '/^ *\. \.\/lib-git-p4\.sh$/i\
	GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=master\
	export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME\
	' t/t980[0167]*.sh t/t9811*.sh

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-11-19 15:44:17 -08:00
Andrei Rybak 64d1022e14 t: fix whitespace around &&
Add missing spaces before '&&' and switch tabs around '&&' to spaces.
Also fix the space after redirection operator in t3701 while we're here.

These issues were found using `git grep '[^ ]&&$'` and
`git grep -P '&&\t' t/`.

Signed-off-by: Andrei Rybak <rybak.a.v@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-22 16:41:05 -07:00
brian m. carlson 277eb5af7c t5604: make hash independent
To make our values hash independent, we turn the directory of the object
into "Y" and the file name into "Z" after having sorted items by their
name. However, when using SHA-256, one of our file names begins with an
"a" character, which means it sorts into the wrong place in the list,
causing the test to fail.

Since we don't care about the order of these items, just sort them after
stripping actual hash contents, which means they'll work with any hash
algorithm.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-15 14:06:19 -08:00
Matheus Tavares 68c7c59cf2 clone: copy hidden paths at local clone
Make the copy_or_link_directory function no longer skip hidden
directories. This function, used to copy .git/objects, currently skips
all hidden directories but not hidden files, which is an odd behaviour.
The reason for that could be unintentional: probably the intention was
to skip '.' and '..' only but it ended up accidentally skipping all
directories starting with '.'. Besides being more natural, the new
behaviour is more permissive to the user.

Also adjust tests to reflect this behaviour change.

Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Co-authored-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-07-11 13:52:15 -07:00
Matheus Tavares 36596fd2df clone: better handle symlinked files at .git/objects/
There is currently an odd behaviour when locally cloning a repository
with symlinks at .git/objects: using --no-hardlinks all symlinks are
dereferenced but without it, Git will try to hardlink the files with the
link() function, which has an OS-specific behaviour on symlinks. On OSX
and NetBSD, it creates a hardlink to the file pointed by the symlink
whilst on GNU/Linux, it creates a hardlink to the symlink itself.

On Manjaro GNU/Linux:
    $ touch a
    $ ln -s a b
    $ link b c
    $ ls -li a b c
    155 [...] a
    156 [...] b -> a
    156 [...] c -> a

But on NetBSD:
    $ ls -li a b c
    2609160 [...] a
    2609164 [...] b -> a
    2609160 [...] c

It's not good to have the result of a local clone to be OS-dependent and
besides that, the current behaviour on GNU/Linux may result in broken
symlinks. So let's standardize this by making the hardlinks always point
to dereferenced paths, instead of the symlinks themselves. Also, add
tests for symlinked files at .git/objects/.

Note: Git won't create symlinks at .git/objects itself, but it's better
to handle this case and be friendly with users who manually create them.

Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Co-authored-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-07-11 13:52:15 -07:00
Ævar Arnfjörð Bjarmason 0315616927 clone: test for our behavior on odd objects/* content
Add tests for what happens when we perform a local clone on a repo
containing odd files at .git/object directory, such as symlinks to other
dirs, or unknown files.

I'm bending over backwards here to avoid a SHA-1 dependency. See [1]
for an earlier and simpler version that hardcoded SHA-1s.

This behavior has been the same for a *long* time, but hasn't been
tested for.

There's a good post-hoc argument to be made for copying over unknown
things, e.g. I'd like a git version that doesn't know about the
commit-graph to copy it under "clone --local" so a newer git version
can make use of it.

In follow-up commits we'll look at changing some of this behavior, but
for now, let's just assert it as-is so we'll notice what we'll change
later.

1. https://public-inbox.org/git/20190226002625.13022-5-avarab@gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
[matheus.bernardino: improved and split tests in more than one patch]
Helped-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-07-11 13:52:15 -07:00
Junio C Hamano 2f03d174f0 Merge branch 'sb/clone-t57-t56'
Rename bunch of tests on "git clone" for better organization.

* sb/clone-t57-t56:
  clone tests: rename t57* => t56*
2016-04-06 11:39:05 -07:00
Stefan Beller 8fbb03a180 clone tests: rename t57* => t56*
When trying to find a good spot for testing clone with submodules, I
got confused where to add a new test file. There are both tests in t560*
as well as t57* both testing the clone command. t/README claims the
second digit is to indicate the command, which is inconsistent to the
current naming structure.

Rename all t57* tests to be in t56* to follow the pattern of the digits
as laid out in t/README.

It would have been less work to rename t56* => t57* because there are less
files, but the tests in t56* look more basic and I assumed the higher the
last digits the more complicated niche details are tested, so with the patch
now it looks more in order to me.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-16 09:41:07 -07:00
Renamed from t/t5700-clone-reference.sh (Browse further)