* maint-2.38: (32 commits)
Git 2.38.5
Git 2.37.7
Git 2.36.6
Git 2.35.8
Git 2.34.8
Git 2.33.8
Git 2.32.7
Git 2.31.8
tests: avoid using `test_i18ncmp`
Git 2.30.9
gettext: avoid using gettext if the locale dir is not present
apply --reject: overwrite existing `.rej` symlink if it exists
http.c: clear the 'finished' member once we are done with it
clone.c: avoid "exceeds maximum object size" error with GCC v12.x
range-diff: use ssize_t for parsed "len" in read_patches()
range-diff: handle unterminated lines in read_patches()
range-diff: drop useless "offset" variable from read_patches()
t5604: GETTEXT_POISON fix, conclusion
t5604: GETTEXT_POISON fix, part 1
t5619: GETTEXT_POISON fix
t0003: GETTEXT_POISON fix, conclusion
...
* maint-2.37: (31 commits)
Git 2.37.7
Git 2.36.6
Git 2.35.8
Git 2.34.8
Git 2.33.8
Git 2.32.7
Git 2.31.8
tests: avoid using `test_i18ncmp`
Git 2.30.9
gettext: avoid using gettext if the locale dir is not present
apply --reject: overwrite existing `.rej` symlink if it exists
http.c: clear the 'finished' member once we are done with it
clone.c: avoid "exceeds maximum object size" error with GCC v12.x
range-diff: use ssize_t for parsed "len" in read_patches()
range-diff: handle unterminated lines in read_patches()
range-diff: drop useless "offset" variable from read_patches()
t5604: GETTEXT_POISON fix, conclusion
t5604: GETTEXT_POISON fix, part 1
t5619: GETTEXT_POISON fix
t0003: GETTEXT_POISON fix, conclusion
t0003: GETTEXT_POISON fix, part 1
...
* maint-2.36: (30 commits)
Git 2.36.6
Git 2.35.8
Git 2.34.8
Git 2.33.8
Git 2.32.7
Git 2.31.8
tests: avoid using `test_i18ncmp`
Git 2.30.9
gettext: avoid using gettext if the locale dir is not present
apply --reject: overwrite existing `.rej` symlink if it exists
http.c: clear the 'finished' member once we are done with it
clone.c: avoid "exceeds maximum object size" error with GCC v12.x
range-diff: use ssize_t for parsed "len" in read_patches()
range-diff: handle unterminated lines in read_patches()
range-diff: drop useless "offset" variable from read_patches()
t5604: GETTEXT_POISON fix, conclusion
t5604: GETTEXT_POISON fix, part 1
t5619: GETTEXT_POISON fix
t0003: GETTEXT_POISON fix, conclusion
t0003: GETTEXT_POISON fix, part 1
t0033: GETTEXT_POISON fix
...
* maint-2.35: (29 commits)
Git 2.35.8
Git 2.34.8
Git 2.33.8
Git 2.32.7
Git 2.31.8
tests: avoid using `test_i18ncmp`
Git 2.30.9
gettext: avoid using gettext if the locale dir is not present
apply --reject: overwrite existing `.rej` symlink if it exists
http.c: clear the 'finished' member once we are done with it
clone.c: avoid "exceeds maximum object size" error with GCC v12.x
range-diff: use ssize_t for parsed "len" in read_patches()
range-diff: handle unterminated lines in read_patches()
range-diff: drop useless "offset" variable from read_patches()
t5604: GETTEXT_POISON fix, conclusion
t5604: GETTEXT_POISON fix, part 1
t5619: GETTEXT_POISON fix
t0003: GETTEXT_POISON fix, conclusion
t0003: GETTEXT_POISON fix, part 1
t0033: GETTEXT_POISON fix
http: support CURLOPT_PROTOCOLS_STR
...
* maint-2.34: (28 commits)
Git 2.34.8
Git 2.33.8
Git 2.32.7
Git 2.31.8
tests: avoid using `test_i18ncmp`
Git 2.30.9
gettext: avoid using gettext if the locale dir is not present
apply --reject: overwrite existing `.rej` symlink if it exists
http.c: clear the 'finished' member once we are done with it
clone.c: avoid "exceeds maximum object size" error with GCC v12.x
range-diff: use ssize_t for parsed "len" in read_patches()
range-diff: handle unterminated lines in read_patches()
range-diff: drop useless "offset" variable from read_patches()
t5604: GETTEXT_POISON fix, conclusion
t5604: GETTEXT_POISON fix, part 1
t5619: GETTEXT_POISON fix
t0003: GETTEXT_POISON fix, conclusion
t0003: GETTEXT_POISON fix, part 1
t0033: GETTEXT_POISON fix
http: support CURLOPT_PROTOCOLS_STR
http: prefer CURLOPT_SEEKFUNCTION to CURLOPT_IOCTLFUNCTION
...
* maint-2.33: (27 commits)
Git 2.33.8
Git 2.32.7
Git 2.31.8
tests: avoid using `test_i18ncmp`
Git 2.30.9
gettext: avoid using gettext if the locale dir is not present
apply --reject: overwrite existing `.rej` symlink if it exists
http.c: clear the 'finished' member once we are done with it
clone.c: avoid "exceeds maximum object size" error with GCC v12.x
range-diff: use ssize_t for parsed "len" in read_patches()
range-diff: handle unterminated lines in read_patches()
range-diff: drop useless "offset" variable from read_patches()
t5604: GETTEXT_POISON fix, conclusion
t5604: GETTEXT_POISON fix, part 1
t5619: GETTEXT_POISON fix
t0003: GETTEXT_POISON fix, conclusion
t0003: GETTEXT_POISON fix, part 1
t0033: GETTEXT_POISON fix
http: support CURLOPT_PROTOCOLS_STR
http: prefer CURLOPT_SEEKFUNCTION to CURLOPT_IOCTLFUNCTION
http-push: prefer CURLOPT_UPLOAD to CURLOPT_PUT
...
* maint-2.32: (26 commits)
Git 2.32.7
Git 2.31.8
tests: avoid using `test_i18ncmp`
Git 2.30.9
gettext: avoid using gettext if the locale dir is not present
apply --reject: overwrite existing `.rej` symlink if it exists
http.c: clear the 'finished' member once we are done with it
clone.c: avoid "exceeds maximum object size" error with GCC v12.x
range-diff: use ssize_t for parsed "len" in read_patches()
range-diff: handle unterminated lines in read_patches()
range-diff: drop useless "offset" variable from read_patches()
t5604: GETTEXT_POISON fix, conclusion
t5604: GETTEXT_POISON fix, part 1
t5619: GETTEXT_POISON fix
t0003: GETTEXT_POISON fix, conclusion
t0003: GETTEXT_POISON fix, part 1
t0033: GETTEXT_POISON fix
http: support CURLOPT_PROTOCOLS_STR
http: prefer CURLOPT_SEEKFUNCTION to CURLOPT_IOCTLFUNCTION
http-push: prefer CURLOPT_UPLOAD to CURLOPT_PUT
ci: install python on ubuntu
...
* maint-2.31: (25 commits)
Git 2.31.8
tests: avoid using `test_i18ncmp`
Git 2.30.9
gettext: avoid using gettext if the locale dir is not present
apply --reject: overwrite existing `.rej` symlink if it exists
http.c: clear the 'finished' member once we are done with it
clone.c: avoid "exceeds maximum object size" error with GCC v12.x
range-diff: use ssize_t for parsed "len" in read_patches()
range-diff: handle unterminated lines in read_patches()
range-diff: drop useless "offset" variable from read_patches()
t5604: GETTEXT_POISON fix, conclusion
t5604: GETTEXT_POISON fix, part 1
t5619: GETTEXT_POISON fix
t0003: GETTEXT_POISON fix, conclusion
t0003: GETTEXT_POISON fix, part 1
t0033: GETTEXT_POISON fix
http: support CURLOPT_PROTOCOLS_STR
http: prefer CURLOPT_SEEKFUNCTION to CURLOPT_IOCTLFUNCTION
http-push: prefer CURLOPT_UPLOAD to CURLOPT_PUT
ci: install python on ubuntu
ci: use the same version of p4 on both Linux and macOS
...
Since `test_i18ncmp` was deprecated in v2.31.*, the instances added in
v2.30.9 needed to be converted to `test_cmp` calls.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
* maint-2.30: (23 commits)
Git 2.30.9
gettext: avoid using gettext if the locale dir is not present
apply --reject: overwrite existing `.rej` symlink if it exists
http.c: clear the 'finished' member once we are done with it
clone.c: avoid "exceeds maximum object size" error with GCC v12.x
range-diff: use ssize_t for parsed "len" in read_patches()
range-diff: handle unterminated lines in read_patches()
range-diff: drop useless "offset" variable from read_patches()
t5604: GETTEXT_POISON fix, conclusion
t5604: GETTEXT_POISON fix, part 1
t5619: GETTEXT_POISON fix
t0003: GETTEXT_POISON fix, conclusion
t0003: GETTEXT_POISON fix, part 1
t0033: GETTEXT_POISON fix
http: support CURLOPT_PROTOCOLS_STR
http: prefer CURLOPT_SEEKFUNCTION to CURLOPT_IOCTLFUNCTION
http-push: prefer CURLOPT_UPLOAD to CURLOPT_PUT
ci: install python on ubuntu
ci: use the same version of p4 on both Linux and macOS
ci: remove the pipe after "p4 -V" to catch errors
github-actions: run gcc-8 on ubuntu-20.04 image
...
Avoids issues with renaming or deleting sections with long lines, where
configuration values may be interpreted as sections, leading to
configuration injection. Addresses CVE-2023-29007.
* tb/config-copy-or-rename-in-file-injection:
config.c: disallow overly-long lines in `copy_or_rename_section_in_file()`
config.c: avoid integer truncation in `copy_or_rename_section_in_file()`
config: avoid fixed-sized buffer when renaming/deleting a section
t1300: demonstrate failure when renaming sections with long lines
Signed-off-by: Taylor Blau <me@ttaylorr.com>
As a defense-in-depth measure to guard against any potentially-unknown
buffer overflows in `copy_or_rename_section_in_file()`, refuse to work
with overly-long lines in a gitconfig.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
When renaming (or deleting) a section of configuration, Git uses the
function `git_config_copy_or_rename_section_in_file()` to rewrite the
configuration file after applying the rename or deletion to the given
section.
To do this, Git repeatedly calls `fgets()` to read the existing
configuration data into a fixed size buffer.
When the configuration value under `old_name` exceeds the size of the
buffer, we will call `fgets()` an additional time even if there is no
newline in the configuration file, since our read length is capped at
`sizeof(buf)`.
If the first character of the buffer (after zero or more characters
satisfying `isspace()`) is a '[', Git will incorrectly treat it as
beginning a new section when the original section is being removed. In
other words, a configuration value satisfying this criteria can
incorrectly be considered as a new secftion instead of a variable in the
original section.
Avoid this issue by using a variable-width buffer in the form of a
strbuf rather than a fixed-with region on the stack. A couple of small
points worth noting:
- Using a strbuf will cause us to allocate arbitrary sizes to match
the length of each line. In practice, we don't expect any
reasonable configuration files to have lines that long, and a
bandaid will be introduced in a later patch to ensure that this is
the case.
- We are using strbuf_getwholeline() here instead of strbuf_getline()
in order to match `fgets()`'s behavior of leaving the trailing LF
character on the buffer (as well as a trailing NUL).
This could be changed later, but using strbuf_getwholeline() changes
the least about this function's implementation, so it is picked as
the safest path.
- It is temping to want to replace the loop to skip over characters
matching isspace() at the beginning of the buffer with a convenience
function like `strbuf_ltrim()`. But this is the wrong approach for a
couple of reasons:
First, it involves a potentially large and expensive `memmove()`
which we would like to avoid. Second, and more importantly, we also
*do* want to preserve those spaces to avoid changing the output of
other sections.
In all, this patch is a minimal replacement of the fixed-width buffer in
`git_config_copy_or_rename_section_in_file()` to instead use a `struct
strbuf`.
Reported-by: André Baptista <andre@ethiack.com>
Reported-by: Vítor Pinho <vitor@ethiack.com>
Helped-by: Patrick Steinhardt <ps@pks.im>
Co-authored-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
When renaming a configuration section which has an entry whose length
exceeds the size of our buffer in config.c's implementation of
`git_config_copy_or_rename_section_in_file()`, Git will incorrectly
form a new configuration section with part of the data in the section
being removed.
In this instance, our first configuration file looks something like:
[b]
c = d <spaces> [a] e = f
[a]
g = h
Here, we have two configuration values, "b.c", and "a.g". The value "[a]
e = f" belongs to the configuration value "b.c", and does not form its
own section.
However, when renaming the section 'a' to 'xyz', Git will write back
"[xyz]\ne = f", but "[xyz]" is still attached to the value of "b.c",
which is why "e = f" on its own line becomes a new entry called "b.e".
A slightly different example embeds the section being renamed within
another section.
Demonstrate this failure in a test in t1300, which we will fix in the
following commit.
Co-authored-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
The `git apply --reject` is expected to write out `.rej` files in case
one or more hunks fail to apply cleanly. Historically, the command
overwrites any existing `.rej` files. The idea being that
apply/reject/edit cycles are relatively common, and the generated `.rej`
files are not considered precious.
But the command does not overwrite existing `.rej` symbolic links, and
instead follows them. This is unsafe because the same patch could
potentially create such a symbolic link and point at arbitrary paths
outside the current worktree, and `git apply` would write the contents
of the `.rej` file into that location.
Therefore, let's make sure that any existing `.rej` file or symbolic
link is removed before writing it.
Reported-by: RyotaK <ryotak.mail@gmail.com>
Helped-by: Taylor Blau <me@ttaylorr.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In fade728df1 (apply: fix writing behind newly created symbolic links,
2023-02-02), we backported a patch onto v2.30.* that was originally
based on a much newer version. The v2.30.* release train still has the
GETTEXT_POISON CI job, though, and hence needs `test_i18n*` in its
tests.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In bffc762f87 (dir-iterator: prevent top-level symlinks without
FOLLOW_SYMLINKS, 2023-01-24), we backported a patch onto v2.30.* that
was originally based on a much newer version. The v2.30.* release train
still has the GETTEXT_POISON CI job, though, and hence needs
`test_i18n*` in its tests.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In cf8f6ce02a (clone: delay picking a transport until after
get_repo_path(), 2023-01-24), we backported a patch onto v2.30.* that
was originally based on a much newer version. The v2.30.* release train
still has the GETTEXT_POISON CI job, though, and hence needs
`test_i18n*` in its tests.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In 3c50032ff5 (attr: ignore overly large gitattributes files,
2022-12-01), we backported a patch onto v2.30.* that was originally
based on a much newer version. The v2.30.* release train still has the
GETTEXT_POISON CI job, though, and hence needs `test_i18n*` in its
tests.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In dfa6b32b5e (attr: ignore attribute lines exceeding 2048 bytes,
2022-12-01), we backported a patch onto v2.30.* that was originally
based on a much newer version. The v2.30.* release train still has the
GETTEXT_POISON CI job, though, and hence needs `test_i18n*` in its
tests.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In e47363e5a8 (t0033: add tests for safe.directory, 2022-04-13), we
backported a patch onto v2.30.* that was originally based on a much
newer version. The v2.30.* release train still has the GETTEXT_POISON
CI job, though, and hence needs `test_i18n*` in its tests.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
"git ls-tree --format='%(path) %(path)' $tree $path" showed the
path three times, which has been corrected.
* rs/ls-tree-path-expansion-fix:
ls-tree: remove dead store and strbuf for quote_c_style()
ls-tree: fix expansion of repeated %(path)
The logic to see if we are using the "cone" mode by checking the
sparsity patterns has been tightened to avoid mistaking a pattern
that names a single file as specifying a cone.
* ws/single-file-cone:
dir: check for single file cone patterns
"git diff --relative" did not mix well with "git diff --ext-diff",
which has been corrected.
* jk/ext-diff-with-relative:
diff: drop "name" parameter from prepare_temp_file()
diff: clean up external-diff argv setup
diff: use filespec path to set up tempfiles for ext-diff
Fix to a small regression in 2.38 days.
* ab/bundle-wo-args:
bundle <cmd>: have usage_msg_opt() note the missing "<file>"
builtin/bundle.c: remove superfluous "newargc" variable
bundle: don't segfault on "git bundle <subcmd>"
When given a pattern that matches an empty string at the end of a
line, the code to parse the "git diff" line-ranges fell into an
infinite loop, which has been corrected.
* lk/line-range-parsing-fix:
line-range: fix infinite loop bug with '$' regex
* maint-2.35:
Git 2.35.7
Git 2.34.7
http: support CURLOPT_PROTOCOLS_STR
http: prefer CURLOPT_SEEKFUNCTION to CURLOPT_IOCTLFUNCTION
http-push: prefer CURLOPT_UPLOAD to CURLOPT_PUT
Git 2.33.7
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
* maint-2.34:
Git 2.34.7
http: support CURLOPT_PROTOCOLS_STR
http: prefer CURLOPT_SEEKFUNCTION to CURLOPT_IOCTLFUNCTION
http-push: prefer CURLOPT_UPLOAD to CURLOPT_PUT
Git 2.33.7
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
* maint-2.33:
Git 2.33.7
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
* 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
* maint-2.31:
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
* 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
Fix a vulnerability (CVE-2023-23946) that allows crafted input to trick
`git apply` into writing files outside of the working tree.
* ps/apply-beyond-symlink:
dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When writing files git-apply(1) initially makes sure that none of the
files it is about to create are behind a symlink:
```
$ git init repo
Initialized empty Git repository in /tmp/repo/.git/
$ cd repo/
$ ln -s dir symlink
$ git apply - <<EOF
diff --git a/symlink/file b/symlink/file
new file mode 100644
index 0000000..e69de29
EOF
error: affected file 'symlink/file' is beyond a symbolic link
```
This safety mechanism is crucial to ensure that we don't write outside
of the repository's working directory. It can be fooled though when the
patch that is being applied creates the symbolic link in the first
place, which can lead to writing files in arbitrary locations.
Fix this by checking whether the path we're about to create is
beyond a symlink or not. Tightening these checks like this should be
fine as we already have these precautions in Git as explained
above. Ideally, we should update the check we do up-front before
starting to reflect the computed changes to the working tree so that
we catch this case as well, but as part of embargoed security work,
adding an equivalent check just before we try to write out a file
should serve us well as a reasonable first step.
Digging back into history shows that this vulnerability has existed
since at least Git v2.9.0. As Git v2.8.0 and older don't build on my
system anymore I cannot tell whether older versions are affected, as
well.
Reported-by: Joern Schneeweisz <jschneeweisz@gitlab.com>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
In the previous commit, t5619 demonstrates an issue where two calls to
`get_repo_path()` could trick Git into using its local clone mechanism
in conjunction with a non-local transport.
That sequence is:
- the starting state is that the local path https:/example.com/foo is a
symlink that points to ../../../.git/modules/foo. So it's dangling.
- get_repo_path() sees that no such path exists (because it's
dangling), and thus we do not canonicalize it into an absolute path
- because we're using --separate-git-dir, we create .git/modules/foo.
Now our symlink is no longer dangling!
- we pass the url to transport_get(), which sees it as an https URL.
- we call get_repo_path() again, on the url. This second call was
introduced by f38aa83f9a (use local cloning if insteadOf makes a
local URL, 2014-07-17). The idea is that we want to pull the url
fresh from the remote.c API, because it will apply any aliases.
And of course now it sees that there is a local file, which is a
mismatch with the transport we already selected.
The issue in the above sequence is calling `transport_get()` before
deciding whether or not the repository is indeed local, and not passing
in an absolute path if it is local.
This is reminiscent of a similar bug report in [1], where it was
suggested to perform the `insteadOf` lookup earlier. Taking that
approach may not be as straightforward, since the intent is to store the
original URL in the config, but to actually fetch from the insteadOf
one, so conflating the two early on is a non-starter.
Note: we pass the path returned by `get_repo_path(remote->url[0])`,
which should be the same as `repo_name` (aside from any `insteadOf`
rewrites).
We *could* pass `absolute_pathdup()` of the same argument, which
86521acaca (Bring local clone's origin URL in line with that of a remote
clone, 2008-09-01) indicates may differ depending on the presence of
".git/" for a non-bare repo. That matters for forming relative submodule
paths, but doesn't matter for the second call, since we're just feeding
it to the transport code, which is fine either way.
[1]: https://lore.kernel.org/git/CAMoD=Bi41mB3QRn3JdZL-FGHs4w3C2jGpnJB-CqSndO7FMtfzA@mail.gmail.com/
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When cloning a repository, Git must determine (a) what transport
mechanism to use, and (b) whether or not the clone is local.
Since f38aa83f9a (use local cloning if insteadOf makes a local URL,
2014-07-17), the latter check happens after the remote has been
initialized, and references the remote's URL instead of the local path.
This is done to make it possible for a `url.<base>.insteadOf` rule to
convert a remote URL into a local one, in which case the `clone_local()`
mechanism should be used.
However, with a specially crafted repository, Git can be tricked into
using a non-local transport while still setting `is_local` to "1" and
using the `clone_local()` optimization. The below test case
demonstrates such an instance, and shows that it can be used to include
arbitrary (known) paths in the working copy of a cloned repository on a
victim's machine[^1], even if local file clones are forbidden by
`protocol.file.allow`.
This happens in a few parts:
1. We first call `get_repo_path()` to see if the remote is a local
path. If it is, we replace the repo name with its absolute path.
2. We then call `transport_get()` on the repo name and decide how to
access it. If it was turned into an absolute path in the previous
step, then we should always treat it like a file.
3. We use `get_repo_path()` again, and set `is_local` as appropriate.
But it's already too late to rewrite the repo name as an absolute
path, since we've already fed it to the transport code.
The attack works by including a submodule whose URL corresponds to a
path on disk. In the below example, the repository "sub" is reachable
via the dumb HTTP protocol at (something like):
http://127.0.0.1:NNNN/dumb/sub.git
However, the path "http:/127.0.0.1:NNNN/dumb" (that is, a top-level
directory called "http:", then nested directories "127.0.0.1:NNNN", and
"dumb") exists within the repository, too.
To determine this, it first picks the appropriate transport, which is
dumb HTTP. It then uses the remote's URL in order to determine whether
the repository exists locally on disk. However, the malicious repository
also contains an embedded stub repository which is the target of a
symbolic link at the local path corresponding to the "sub" repository on
disk (i.e., there is a symbolic link at "http:/127.0.0.1/dumb/sub.git",
pointing to the stub repository via ".git/modules/sub/../../../repo").
This stub repository fools Git into thinking that a local repository
exists at that URL and thus can be cloned locally. The affected call is
in `get_repo_path()`, which in turn calls `get_repo_path_1()`, which
locates a valid repository at that target.
This then causes Git to set the `is_local` variable to "1", and in turn
instructs Git to clone the repository using its local clone optimization
via the `clone_local()` function.
The exploit comes into play because the stub repository's top-level
"$GIT_DIR/objects" directory is a symbolic link which can point to an
arbitrary path on the victim's machine. `clone_local()` resolves the
top-level "objects" directory through a `stat(2)` call, meaning that we
read through the symbolic link and copy or hardlink the directory
contents at the destination of the link.
In other words, we can get steps (1) and (3) to disagree by leveraging
the dangling symlink to pick a non-local transport in the first step,
and then set is_local to "1" in the third step when cloning with
`--separate-git-dir`, which makes the symlink non-dangling.
This can result in data-exfiltration on the victim's machine when
sensitive data is at a known path (e.g., "/home/$USER/.ssh").
The appropriate fix is two-fold:
- Resolve the transport later on (to avoid using the local
clone optimization with a non-local transport).
- Avoid reading through the top-level "objects" directory when
(correctly) using the clone_local() optimization.
This patch merely demonstrates the issue. The following two patches will
implement each part of the above fix, respectively.
[^1]: Provided that any target directory does not contain symbolic
links, in which case the changes from 6f054f9fb3 (builtin/clone.c:
disallow `--local` clones with symlinks, 2022-07-28) will abort the
clone.
Reported-by: yvvdwf <yvvdwf@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
expand_show_tree() borrows the base strbuf given to us by read_tree() to
build the full path of the current entry when handling %(path). Only
its indirect caller, show_tree_fmt(), removes the added entry name.
That works fine as long as %(path) is only included once in the format
string, but accumulates duplicates if it's repeated:
$ git ls-tree --format='%(path) %(path) %(path)' HEAD M*
Makefile MakefileMakefile MakefileMakefileMakefile
Reset the length after each use to get the same expansion every time;
here's the behavior with this patch:
$ ./git ls-tree --format='%(path) %(path) %(path)' HEAD M*
Makefile Makefile Makefile
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we're going to run an external diff, we have to make the contents
of the pre- and post-images available either by dumping them to a
tempfile, or by pointing at a valid file in the worktree. The logic of
this is all handled by prepare_temp_file(), and we just pass in the
filename and the diff_filespec.
But there's a gotcha here. The "filename" we have is a logical filename
and not necessarily a path on disk or in the repository. This matters in
at least one case: when using "--relative", we may have a name like
"foo", even though the file content is found at "subdir/foo". As a
result, we look for the wrong path, fail to find "foo", and claim that
the file has been deleted (passing "/dev/null" to the external diff,
rather than the correct worktree path).
We can fix this by passing the pathname from the diff_filespec, which
should always be a full repository path (and that's what we want even if
reusing a worktree file, since we're always operating from the top-level
of the working tree).
The breakage seems to go all the way back to cd676a5136 (diff
--relative: output paths as relative to the current subdirectory,
2008-02-12). As far as I can tell, before then "name" would always have
been the same as the filespec's "path".
There are two related cases I looked at that aren't buggy:
1. the only other caller of prepare_temp_file() is run_textconv(). But
it always passes the filespec's path field, so it's OK.
2. I wondered if file renames/copies might cause similar confusion.
But they don't, because run_external_diff() receives two names in
that case: "name" and "other", which correspond to the two sides of
the diff. And we did correctly pass "other" when handling the
post-image side. Barring the use of "--relative", that would always
match "two->path", the path of the second filespec (and the rename
destination).
So the only bug is just the interaction with external diff drivers and
--relative.
Reported-by: Carl Baldwin <carl@ecbaldwin.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The sparse checkout documentation states that the cone mode pattern set
is limited to patterns that either recursively include directories or
patterns that match all files in a directory. In the sparse checkout
file, the former manifest in the form:
/A/B/C/
while the latter become a pair of patterns either in the form:
/A/B/
!/A/B/*/
or in the special case of matching the toplevel files:
/*
!/*/
The 'add_pattern_to_hashsets()' function contains checks which serve to
disable cone-mode when non-cone patterns are encountered. However, these
do not catch when the pattern list attempts to match a single file or
directory, e.g. a pattern in the form:
/A/B/C
This causes sparse-checkout to exhibit unexpected behaviour when such a
pattern is in the sparse-checkout file and cone mode is enabled.
Concretely, with the pattern like the above, sparse-checkout, in
non-cone mode, will only include the directory or file located at
'/A/B/C'. However, with cone mode enabled, sparse-checkout will instead
just manifest the toplevel files but not any file located at '/A/B/C'.
Relatedly, issues occur when supplying the same kind of filter when
partial cloning with '--filter=sparse:oid=<oid>'. 'upload-pack' will
correctly just include the objects that match the non-cone pattern
matching. Which means that checking out the newly cloned repo with the
same filter, but with cone mode enabled, fails due to missing objects.
To fix these issues, add a cone mode pattern check that asserts that
every pattern is either a directory match or the pattern '/*'. Add a
test to verify the new pattern check and modify another to reflect that
non-directory patterns are caught earlier.
Signed-off-by: William Sprent <williams@unity3d.com>
Acked-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
