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!154 Fix CVE-2024-32021 CVE-2024-32004 CVE-2024-32020 CVE-2024-32465

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From: @fly_fzc 
Reviewed-by: @dillon_chen 
Signed-off-by: @dillon_chen
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openeuler-ci-bot 2024-05-17 03:25:22 +00:00 committed by Gitee
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153
backport-CVE-2024-32004-fetch-clone-detect-dubious-ownership-of-local-reposi.patch Normal file
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@ -0,0 +1,153 @@
From f4aa8c8bb11dae6e769cd930565173808cbb69c8 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 10 Apr 2024 14:39:37 +0200
Subject: [PATCH] fetch/clone: detect dubious ownership of local repositories
When cloning from somebody else's repositories, it is possible that,
say, the `upload-pack` command is overridden in the repository that is
about to be cloned, which would then be run in the user's context who
started the clone.
To remind the user that this is a potentially unsafe operation, let's
extend the ownership checks we have already established for regular
gitdir discovery to extend also to local repositories that are about to
be cloned.
This protection extends also to file:// URLs.
The fixes in this commit address CVE-2024-32004.
Note: This commit does not touch the `fetch`/`clone` code directly, but
instead the function used implicitly by both: `enter_repo()`. This
function is also used by `git receive-pack` (i.e. pushes), by `git
upload-archive`, by `git daemon` and by `git http-backend`. In setups
that want to serve repositories owned by different users than the
account running the service, this will require `safe.*` settings to be
configured accordingly.
Also note: there are tiny time windows where a time-of-check-time-of-use
("TOCTOU") race is possible. The real solution to those would be to work
with `fstat()` and `openat()`. However, the latter function is not
available on Windows (and would have to be emulated with rather
expensive low-level `NtCreateFile()` calls), and the changes would be
quite extensive, for my taste too extensive for the little gain given
that embargoed releases need to pay extra attention to avoid introducing
inadvertent bugs.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
setup.h | 12 ++++++++++++
path.c | 2 ++
setup.c | 21 +++++++++++++++++++++
t/t0411-clone-from-partial.sh | 6 +++---
4 files changed, 38 insertions(+), 3 deletions(-)
diff --git a/setup.h b/setup.h
index fcf49706a..a46a3e4b6 100644
--- a/setup.h
+++ b/setup.h
@@ -41,6 +41,18 @@ const char *read_gitfile_gently(const char *path, int *return_error_code);
const char *resolve_gitdir_gently(const char *suspect, int *return_error_code);
#define resolve_gitdir(path) resolve_gitdir_gently((path), NULL)
+/*
+ * Check if a repository is safe and die if it is not, by verifying the
+ * ownership of the worktree (if any), the git directory, and the gitfile (if
+ * any).
+ *
+ * Exemptions for known-safe repositories can be added via `safe.directory`
+ * config settings; for non-bare repositories, their worktree needs to be
+ * added, for bare ones their git directory.
+ */
+void die_upon_dubious_ownership(const char *gitfile, const char *worktree,
+ const char *gitdir);
+
void setup_work_tree(void);
/*
diff --git a/path.c b/path.c
index 492e17ad1..d61f70e87 100644
--- a/path.c
+++ b/path.c
@@ -840,6 +840,7 @@ const char *enter_repo(const char *path, int strict)
if (!suffix[i])
return NULL;
gitfile = read_gitfile(used_path.buf);
+ die_upon_dubious_ownership(gitfile, NULL, used_path.buf);
if (gitfile) {
strbuf_reset(&used_path);
strbuf_addstr(&used_path, gitfile);
@@ -850,6 +851,7 @@ const char *enter_repo(const char *path, int strict)
}
else {
const char *gitfile = read_gitfile(path);
+ die_upon_dubious_ownership(gitfile, NULL, path);
if (gitfile)
path = gitfile;
if (chdir(path))
diff --git a/setup.c b/setup.c
index cefd5f63c..9d401ae4c 100644
--- a/setup.c
+++ b/setup.c
@@ -1165,6 +1165,27 @@ static int ensure_valid_ownership(const char *gitfile,
return data.is_safe;
}
+void die_upon_dubious_ownership(const char *gitfile, const char *worktree,
+ const char *gitdir)
+{
+ struct strbuf report = STRBUF_INIT, quoted = STRBUF_INIT;
+ const char *path;
+
+ if (ensure_valid_ownership(gitfile, worktree, gitdir, &report))
+ return;
+
+ strbuf_complete(&report, '\n');
+ path = gitfile ? gitfile : gitdir;
+ sq_quote_buf_pretty(&quoted, path);
+
+ die(_("detected dubious ownership in repository at '%s'\n"
+ "%s"
+ "To add an exception for this directory, call:\n"
+ "\n"
+ "\tgit config --global --add safe.directory %s"),
+ path, report.buf, quoted.buf);
+}
+
static int allowed_bare_repo_cb(const char *key, const char *value,
const struct config_context *ctx UNUSED,
void *d)
diff --git a/t/t0411-clone-from-partial.sh b/t/t0411-clone-from-partial.sh
index fb72a0a9f..eb3360dbc 100755
--- a/t/t0411-clone-from-partial.sh
+++ b/t/t0411-clone-from-partial.sh
@@ -23,7 +23,7 @@ test_expect_success 'create evil repo' '
>evil/.git/shallow
'
-test_expect_failure 'local clone must not fetch from promisor remote and execute script' '
+test_expect_success 'local clone must not fetch from promisor remote and execute script' '
rm -f script-executed &&
test_must_fail git clone \
--upload-pack="GIT_TEST_ASSUME_DIFFERENT_OWNER=true git-upload-pack" \
@@ -32,7 +32,7 @@ test_expect_failure 'local clone must not fetch from promisor remote and execute
test_path_is_missing script-executed
'
-test_expect_failure 'clone from file://... must not fetch from promisor remote and execute script' '
+test_expect_success 'clone from file://... must not fetch from promisor remote and execute script' '
rm -f script-executed &&
test_must_fail git clone \
--upload-pack="GIT_TEST_ASSUME_DIFFERENT_OWNER=true git-upload-pack" \
@@ -41,7 +41,7 @@ test_expect_failure 'clone from file://... must not fetch from promisor remote a
test_path_is_missing script-executed
'
-test_expect_failure 'fetch from file://... must not fetch from promisor remote and execute script' '
+test_expect_success 'fetch from file://... must not fetch from promisor remote and execute script' '
rm -f script-executed &&
test_must_fail git fetch \
--upload-pack="GIT_TEST_ASSUME_DIFFERENT_OWNER=true git-upload-pack" \
--
2.33.0

90
backport-CVE-2024-32004-t0411-add-tests-for-cloning-from-partial-repo.patch Normal file
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@ -0,0 +1,90 @@
From 5c5a4a1c05932378d259b1fdd9526cab971656a2 Mon Sep 17 00:00:00 2001
From: Filip Hejsek <filip.hejsek@gmail.com>
Date: Sun, 28 Jan 2024 04:29:33 +0100
Subject: [PATCH] t0411: add tests for cloning from partial repo
Cloning from a partial repository must not fetch missing objects into
the partial repository, because that can lead to arbitrary code
execution.
Add a couple of test cases, pretending to the `upload-pack` command (and
to that command only) that it is working on a repository owned by
someone else.
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Filip Hejsek <filip.hejsek@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
t/t0411-clone-from-partial.sh | 60 +++++++++++++++++++++++++++++++++++
1 file changed, 60 insertions(+)
create mode 100755 t/t0411-clone-from-partial.sh
diff --git a/t/t0411-clone-from-partial.sh b/t/t0411-clone-from-partial.sh
new file mode 100755
index 000000000..fb72a0a9f
--- /dev/null
+++ b/t/t0411-clone-from-partial.sh
@@ -0,0 +1,60 @@
+#!/bin/sh
+
+test_description='check that local clone does not fetch from promisor remotes'
+
+. ./test-lib.sh
+
+test_expect_success 'create evil repo' '
+ git init tmp &&
+ test_commit -C tmp a &&
+ git -C tmp config uploadpack.allowfilter 1 &&
+ git clone --filter=blob:none --no-local --no-checkout tmp evil &&
+ rm -rf tmp &&
+
+ git -C evil config remote.origin.uploadpack \"\$TRASH_DIRECTORY/fake-upload-pack\" &&
+ write_script fake-upload-pack <<-\EOF &&
+ echo >&2 "fake-upload-pack running"
+ >"$TRASH_DIRECTORY/script-executed"
+ exit 1
+ EOF
+ export TRASH_DIRECTORY &&
+
+ # empty shallow file disables local clone optimization
+ >evil/.git/shallow
+'
+
+test_expect_failure 'local clone must not fetch from promisor remote and execute script' '
+ rm -f script-executed &&
+ test_must_fail git clone \
+ --upload-pack="GIT_TEST_ASSUME_DIFFERENT_OWNER=true git-upload-pack" \
+ evil clone1 2>err &&
+ ! grep "fake-upload-pack running" err &&
+ test_path_is_missing script-executed
+'
+
+test_expect_failure 'clone from file://... must not fetch from promisor remote and execute script' '
+ rm -f script-executed &&
+ test_must_fail git clone \
+ --upload-pack="GIT_TEST_ASSUME_DIFFERENT_OWNER=true git-upload-pack" \
+ "file://$(pwd)/evil" clone2 2>err &&
+ ! grep "fake-upload-pack running" err &&
+ test_path_is_missing script-executed
+'
+
+test_expect_failure 'fetch from file://... must not fetch from promisor remote and execute script' '
+ rm -f script-executed &&
+ test_must_fail git fetch \
+ --upload-pack="GIT_TEST_ASSUME_DIFFERENT_OWNER=true git-upload-pack" \
+ "file://$(pwd)/evil" 2>err &&
+ ! grep "fake-upload-pack running" err &&
+ test_path_is_missing script-executed
+'
+
+test_expect_success 'pack-objects should fetch from promisor remote and execute script' '
+ rm -f script-executed &&
+ echo "HEAD" | test_must_fail git -C evil pack-objects --revs --stdout >/dev/null 2>err &&
+ grep "fake-upload-pack running" err &&
+ test_path_is_file script-executed
+'
+
+test_done
--
2.33.0

109
backport-CVE-2024-32020-builtin-clone-refuse-local-clones-of-unsafe-reposito.patch Normal file
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@ -0,0 +1,109 @@
From 1204e1a824c34071019fe106348eaa6d88f9528d Mon Sep 17 00:00:00 2001
From: Patrick Steinhardt <ps@pks.im>
Date: Mon, 15 Apr 2024 13:30:41 +0200
Subject: [PATCH] builtin/clone: refuse local clones of unsafe repositories
When performing a local clone of a repository we end up either copying
or hardlinking the source repository into the target repository. This is
significantly more performant than if we were to use git-upload-pack(1)
and git-fetch-pack(1) to create the new repository and preserves both
disk space and compute time.
Unfortunately though, performing such a local clone of a repository that
is not owned by the current user is inherently unsafe:
- It is possible that source files get swapped out underneath us while
we are copying or hardlinking them. While we do perform some checks
here to assert that we hardlinked the expected file, they cannot
reliably thwart time-of-check-time-of-use (TOCTOU) style races. It
is thus possible for an adversary to make us copy or hardlink
unexpected files into the target directory.
Ideally, we would address this by starting to use openat(3P),
fstatat(3P) and friends. Due to platform compatibility with Windows
we cannot easily do that though. Furthermore, the scope of these
fixes would likely be quite broad and thus not fit for an embargoed
security release.
- Even if we handled TOCTOU-style races perfectly, hardlinking files
owned by a different user into the target repository is not a good
idea in general. It is possible for an adversary to rewrite those
files to contain whatever data they want even after the clone has
completed.
Address these issues by completely refusing local clones of a repository
that is not owned by the current user. This reuses our existing infra we
have in place via `ensure_valid_ownership()` and thus allows a user to
override the safety guard by adding the source repository path to the
"safe.directory" configuration.
This addresses CVE-2024-32020.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
builtin/clone.c | 14 ++++++++++++++
t/t0033-safe-directory.sh | 24 ++++++++++++++++++++++++
2 files changed, 38 insertions(+)
diff --git a/builtin/clone.c b/builtin/clone.c
index 4b80fa087..9ec500d42 100644
--- a/builtin/clone.c
+++ b/builtin/clone.c
@@ -321,6 +321,20 @@ static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
struct dir_iterator *iter;
int iter_status;
+ /*
+ * Refuse copying directories by default which aren't owned by us. The
+ * code that performs either the copying or hardlinking is not prepared
+ * to handle various edge cases where an adversary may for example
+ * racily swap out files for symlinks. This can cause us to
+ * inadvertently use the wrong source file.
+ *
+ * Furthermore, even if we were prepared to handle such races safely,
+ * creating hardlinks across user boundaries is an inherently unsafe
+ * operation as the hardlinked files can be rewritten at will by the
+ * potentially-untrusted user. We thus refuse to do so by default.
+ */
+ die_upon_dubious_ownership(NULL, NULL, src_repo);
+
mkdir_if_missing(dest->buf, 0777);
iter = dir_iterator_begin(src->buf, DIR_ITERATOR_PEDANTIC);
diff --git a/t/t0033-safe-directory.sh b/t/t0033-safe-directory.sh
index dc3496897..11c3e8f28 100755
--- a/t/t0033-safe-directory.sh
+++ b/t/t0033-safe-directory.sh
@@ -80,4 +80,28 @@ test_expect_success 'safe.directory in included file' '
git status
'
+test_expect_success 'local clone of unowned repo refused in unsafe directory' '
+ test_when_finished "rm -rf source" &&
+ git init source &&
+ (
+ sane_unset GIT_TEST_ASSUME_DIFFERENT_OWNER &&
+ test_commit -C source initial
+ ) &&
+ test_must_fail git clone --local source target &&
+ test_path_is_missing target
+'
+
+test_expect_success 'local clone of unowned repo accepted in safe directory' '
+ test_when_finished "rm -rf source" &&
+ git init source &&
+ (
+ sane_unset GIT_TEST_ASSUME_DIFFERENT_OWNER &&
+ test_commit -C source initial
+ ) &&
+ test_must_fail git clone --local source target &&
+ git config --global --add safe.directory "$(pwd)/source/.git" &&
+ git clone --local source target &&
+ test_path_is_dir target
+'
+
test_done
--
2.33.0

60
backport-CVE-2024-32021-builtin-clone-abort-when-hardlinked-source-and-targe.patch Normal file
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@ -0,0 +1,60 @@
From d1bb66a546b4bb46005d17ba711caaad26f26c1e Mon Sep 17 00:00:00 2001
From: Patrick Steinhardt <ps@pks.im>
Date: Mon, 15 Apr 2024 13:30:31 +0200
Subject: [PATCH] builtin/clone: abort when hardlinked source and target file
differ
When performing local clones with hardlinks we refuse to copy source
files which are symlinks as a mitigation for CVE-2022-39253. This check
can be raced by an adversary though by changing the file to a symlink
after we have checked it.
Fix the issue by checking whether the hardlinked destination file
matches the source file and abort in case it doesn't.
This addresses CVE-2024-32021.
Reported-by: Apple Product Security <product-security@apple.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
builtin/clone.c | 21 ++++++++++++++++++++-
1 file changed, 20 insertions(+), 1 deletion(-)
diff --git a/builtin/clone.c b/builtin/clone.c
index 073e6323d..4b80fa087 100644
--- a/builtin/clone.c
+++ b/builtin/clone.c
@@ -357,8 +357,27 @@ static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
if (unlink(dest->buf) && errno != ENOENT)
die_errno(_("failed to unlink '%s'"), dest->buf);
if (!option_no_hardlinks) {
- if (!link(src->buf, dest->buf))
+ if (!link(src->buf, dest->buf)) {
+ struct stat st;
+
+ /*
+ * Sanity-check whether the created hardlink
+ * actually links to the expected file now. This
+ * catches time-of-check-time-of-use bugs in
+ * case the source file was meanwhile swapped.
+ */
+ if (lstat(dest->buf, &st))
+ die(_("hardlink cannot be checked at '%s'"), dest->buf);
+ if (st.st_mode != iter->st.st_mode ||
+ st.st_ino != iter->st.st_ino ||
+ st.st_dev != iter->st.st_dev ||
+ st.st_size != iter->st.st_size ||
+ st.st_uid != iter->st.st_uid ||
+ st.st_gid != iter->st.st_gid)
+ die(_("hardlink different from source at '%s'"), dest->buf);
+
continue;
+ }
if (option_local > 0)
die_errno(_("failed to create link '%s'"), dest->buf);
option_no_hardlinks = 1;
--
2.33.0

84
backport-CVE-2024-32021-builtin-clone-stop-resolving-symlinks-when-copying-f.patch Normal file
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@ -0,0 +1,84 @@
From 150e6b0aedf57d224c3c49038c306477fa159886 Mon Sep 17 00:00:00 2001
From: Patrick Steinhardt <ps@pks.im>
Date: Mon, 15 Apr 2024 13:30:26 +0200
Subject: [PATCH] builtin/clone: stop resolving symlinks when copying files
When a user performs a local clone without `--no-local`, then we end up
copying the source repository into the target repository directly. To
optimize this even further, we try to hardlink files into place instead
of copying data over, which helps both disk usage and speed.
There is an important edge case in this context though, namely when we
try to hardlink symlinks from the source repository into the target
repository. Depending on both platform and filesystem the resulting
behaviour here can be different:
- On macOS and NetBSD, calling link(3P) with a symlink target creates
a hardlink to the file pointed to by the symlink.
- On Linux, calling link(3P) instead creates a hardlink to the symlink
itself.
To unify this behaviour, 36596fd2df (clone: better handle symlinked
files at .git/objects/, 2019-07-10) introduced logic to resolve symlinks
before we try to link(3P) files. Consequently, the new behaviour was to
always create a hard link to the target of the symlink on all platforms.
Eventually though, we figured out that following symlinks like this can
cause havoc when performing a local clone of a malicious repository,
which resulted in CVE-2022-39253. This issue was fixed via 6f054f9fb3
(builtin/clone.c: disallow `--local` clones with symlinks, 2022-07-28),
by refusing symlinks in the source repository.
But even though we now shouldn't ever link symlinks anymore, the code
that resolves symlinks still exists. In the best case the code does not
end up doing anything because there are no symlinks anymore. In the
worst case though this can be abused by an adversary that rewrites the
source file after it has been checked not to be a symlink such that it
actually is a symlink when we call link(3P). Thus, it is still possible
to recreate CVE-2022-39253 due to this time-of-check-time-of-use bug.
Remove the call to `realpath()`. This doesn't yet address the actual
vulnerability, which will be handled in a subsequent commit.
Reported-by: Apple Product Security <product-security@apple.com>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
builtin/clone.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/builtin/clone.c b/builtin/clone.c
index 3c2ae31a5..073e6323d 100644
--- a/builtin/clone.c
+++ b/builtin/clone.c
@@ -320,7 +320,6 @@ static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
int src_len, dest_len;
struct dir_iterator *iter;
int iter_status;
- struct strbuf realpath = STRBUF_INIT;
mkdir_if_missing(dest->buf, 0777);
@@ -358,8 +357,7 @@ static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
if (unlink(dest->buf) && errno != ENOENT)
die_errno(_("failed to unlink '%s'"), dest->buf);
if (!option_no_hardlinks) {
- strbuf_realpath(&realpath, src->buf, 1);
- if (!link(realpath.buf, dest->buf))
+ if (!link(src->buf, dest->buf))
continue;
if (option_local > 0)
die_errno(_("failed to create link '%s'"), dest->buf);
@@ -373,8 +371,6 @@ static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
strbuf_setlen(src, src_len);
die(_("failed to iterate over '%s'"), src->buf);
}
-
- strbuf_release(&realpath);
}
static void clone_local(const char *src_repo, const char *dest_repo)
--
2.33.0

201
backport-CVE-2024-32465-upload-pack-disable-lazy-fetching-by-default.patch Normal file
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@ -0,0 +1,201 @@
From 7b70e9efb18c2cc3f219af399bd384c5801ba1d7 Mon Sep 17 00:00:00 2001
From: Jeff King <peff@peff.net>
Date: Tue, 16 Apr 2024 04:35:33 -0400
Subject: [PATCH] upload-pack: disable lazy-fetching by default
The upload-pack command tries to avoid trusting the repository in which
it's run (e.g., by not running any hooks and not using any config that
contains arbitrary commands). But if the server side of a fetch or a
clone is a partial clone, then either upload-pack or its child
pack-objects may run a lazy "git fetch" under the hood. And it is very
easy to convince fetch to run arbitrary commands.
The "server" side can be a local repository owned by someone else, who
would be able to configure commands that are run during a clone with the
current user's permissions. This issue has been designated
CVE-2024-32004.
The fix in this commit's parent helps in this scenario, as well as in
related scenarios using SSH to clone, where the untrusted .git directory
is owned by a different user id. But if you received one as a zip file,
on a USB stick, etc, it may be owned by your user but still untrusted.
This has been designated CVE-2024-32465.
To mitigate the issue more completely, let's disable lazy fetching
entirely during `upload-pack`. While fetching from a partial repository
should be relatively rare, it is certainly not an unreasonable workflow.
And thus we need to provide an escape hatch.
This commit works by respecting a GIT_NO_LAZY_FETCH environment variable
(to skip the lazy-fetch), and setting it in upload-pack, but only when
the user has not already done so (which gives us the escape hatch).
The name of the variable is specifically chosen to match what has
already been added in 'master' via e6d5479e7a (git: extend
--no-lazy-fetch to work across subprocesses, 2024-02-27). Since we're
building this fix as a backport for older versions, we could cherry-pick
that patch and its earlier steps. However, we don't really need the
niceties (like a "--no-lazy-fetch" option) that it offers. By using the
same name, everything should just work when the two are eventually
merged, but here are a few notes:
- the blocking of the fetch in e6d5479e7a is incomplete! It sets
fetch_if_missing to 0 when we setup the repository variable, but
that isn't enough. pack-objects in particular will call
prefetch_to_pack() even if that variable is 0. This patch by
contrast checks the environment variable at the lowest level before
we call the lazy fetch, where we can be sure to catch all code
paths.
Possibly the setting of fetch_if_missing from e6d5479e7a can be
reverted, but it may be useful to have. For example, some code may
want to use that flag to change behavior before it gets to the point
of trying to start the fetch. At any rate, that's all outside the
scope of this patch.
- there's documentation for GIT_NO_LAZY_FETCH in e6d5479e7a. We can
live without that here, because for the most part the user shouldn't
need to set it themselves. The exception is if they do want to
override upload-pack's default, and that requires a separate
documentation section (which is added here)
- it would be nice to use the NO_LAZY_FETCH_ENVIRONMENT macro added by
e6d5479e7a, but those definitions have moved from cache.h to
environment.h between 2.39.3 and master. I just used the raw string
literals, and we can replace them with the macro once this topic is
merged to master.
At least with respect to CVE-2024-32004, this does render this commit's
parent commit somewhat redundant. However, it is worth retaining that
commit as defense in depth, and because it may help other issues (e.g.,
symlink/hardlink TOCTOU races, where zip files are not really an
interesting attack vector).
The tests in t0411 still pass, but now we have _two_ mechanisms ensuring
that the evil command is not run. Let's beef up the existing ones to
check that they failed for the expected reason, that we refused to run
upload-pack at all with an alternate user id. And add two new ones for
the same-user case that both the restriction and its escape hatch.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
Documentation/git-upload-pack.txt | 16 ++++++++++++++++
builtin/upload-pack.c | 2 ++
promisor-remote.c | 10 ++++++++++
t/t0411-clone-from-partial.sh | 18 ++++++++++++++++++
4 files changed, 46 insertions(+)
diff --git a/Documentation/git-upload-pack.txt b/Documentation/git-upload-pack.txt
index b656b4756..fc4c62d7b 100644
--- a/Documentation/git-upload-pack.txt
+++ b/Documentation/git-upload-pack.txt
@@ -55,6 +55,22 @@ ENVIRONMENT
admins may need to configure some transports to allow this
variable to be passed. See the discussion in linkgit:git[1].
+`GIT_NO_LAZY_FETCH`::
+ When cloning or fetching from a partial repository (i.e., one
+ itself cloned with `--filter`), the server-side `upload-pack`
+ may need to fetch extra objects from its upstream in order to
+ complete the request. By default, `upload-pack` will refuse to
+ perform such a lazy fetch, because `git fetch` may run arbitrary
+ commands specified in configuration and hooks of the source
+ repository (and `upload-pack` tries to be safe to run even in
+ untrusted `.git` directories).
++
+This is implemented by having `upload-pack` internally set the
+`GIT_NO_LAZY_FETCH` variable to `1`. If you want to override it
+(because you are fetching from a partial clone, and you are sure
+you trust it), you can explicitly set `GIT_NO_LAZY_FETCH` to
+`0`.
+
SEE ALSO
--------
linkgit:gitnamespaces[7]
diff --git a/builtin/upload-pack.c b/builtin/upload-pack.c
index 25b69da2b..f446ff04f 100644
--- a/builtin/upload-pack.c
+++ b/builtin/upload-pack.c
@@ -35,6 +35,8 @@ int cmd_upload_pack(int argc, const char **argv, const char *prefix)
packet_trace_identity("upload-pack");
disable_replace_refs();
+ /* TODO: This should use NO_LAZY_FETCH_ENVIRONMENT */
+ xsetenv("GIT_NO_LAZY_FETCH", "1", 0);
argc = parse_options(argc, argv, prefix, options, upload_pack_usage, 0);
diff --git a/promisor-remote.c b/promisor-remote.c
index faa761294..550a38f75 100644
--- a/promisor-remote.c
+++ b/promisor-remote.c
@@ -20,6 +20,16 @@ static int fetch_objects(struct repository *repo,
int i;
FILE *child_in;
+ /* TODO: This should use NO_LAZY_FETCH_ENVIRONMENT */
+ if (git_env_bool("GIT_NO_LAZY_FETCH", 0)) {
+ static int warning_shown;
+ if (!warning_shown) {
+ warning_shown = 1;
+ warning(_("lazy fetching disabled; some objects may not be available"));
+ }
+ return -1;
+ }
+
child.git_cmd = 1;
child.in = -1;
if (repo != the_repository)
diff --git a/t/t0411-clone-from-partial.sh b/t/t0411-clone-from-partial.sh
index eb3360dbc..b3d6ddc4b 100755
--- a/t/t0411-clone-from-partial.sh
+++ b/t/t0411-clone-from-partial.sh
@@ -28,6 +28,7 @@ test_expect_success 'local clone must not fetch from promisor remote and execute
test_must_fail git clone \
--upload-pack="GIT_TEST_ASSUME_DIFFERENT_OWNER=true git-upload-pack" \
evil clone1 2>err &&
+ grep "detected dubious ownership" err &&
! grep "fake-upload-pack running" err &&
test_path_is_missing script-executed
'
@@ -37,6 +38,7 @@ test_expect_success 'clone from file://... must not fetch from promisor remote a
test_must_fail git clone \
--upload-pack="GIT_TEST_ASSUME_DIFFERENT_OWNER=true git-upload-pack" \
"file://$(pwd)/evil" clone2 2>err &&
+ grep "detected dubious ownership" err &&
! grep "fake-upload-pack running" err &&
test_path_is_missing script-executed
'
@@ -46,6 +48,7 @@ test_expect_success 'fetch from file://... must not fetch from promisor remote a
test_must_fail git fetch \
--upload-pack="GIT_TEST_ASSUME_DIFFERENT_OWNER=true git-upload-pack" \
"file://$(pwd)/evil" 2>err &&
+ grep "detected dubious ownership" err &&
! grep "fake-upload-pack running" err &&
test_path_is_missing script-executed
'
@@ -57,4 +60,19 @@ test_expect_success 'pack-objects should fetch from promisor remote and execute
test_path_is_file script-executed
'
+test_expect_success 'clone from promisor remote does not lazy-fetch by default' '
+ rm -f script-executed &&
+ test_must_fail git clone evil no-lazy 2>err &&
+ grep "lazy fetching disabled" err &&
+ test_path_is_missing script-executed
+'
+
+test_expect_success 'promisor lazy-fetching can be re-enabled' '
+ rm -f script-executed &&
+ test_must_fail env GIT_NO_LAZY_FETCH=0 \
+ git clone evil lazy-ok 2>err &&
+ grep "fake-upload-pack running" err &&
+ test_path_is_file script-executed
+'
+
test_done
--
2.33.0

14
git.spec
View File

@ -1,7 +1,7 @@
%global gitexecdir %{_libexecdir}/git-core
Name: git
Version: 2.43.0
Release: 3
Release: 4
Summary: A popular and widely used Version Control System
License: GPLv2+ or LGPLv2.1
URL: https://git-scm.com/
@ -14,6 +14,12 @@ Source102: git.socket
Patch0: backport-send-email-avoid-duplicate-specification-warnings.patch
Patch1: backport-CVE-2024-32002-submodules-submodule-paths-m.patch
Patch2: backport-CVE-2024-32021-builtin-clone-stop-resolving-symlinks-when-copying-f.patch
Patch3: backport-CVE-2024-32021-builtin-clone-abort-when-hardlinked-source-and-targe.patch
Patch4: backport-CVE-2024-32004-t0411-add-tests-for-cloning-from-partial-repo.patch
Patch5: backport-CVE-2024-32004-fetch-clone-detect-dubious-ownership-of-local-reposi.patch
Patch6: backport-CVE-2024-32020-builtin-clone-refuse-local-clones-of-unsafe-reposito.patch
Patch7: backport-CVE-2024-32465-upload-pack-disable-lazy-fetching-by-default.patch
BuildRequires: gcc gettext
BuildRequires: openssl-devel libcurl-devel expat-devel systemd asciidoc xmlto glib2-devel libsecret-devel pcre2-devel desktop-file-utils
@ -298,6 +304,12 @@ make %{?_smp_mflags} test
%{_mandir}/man7/git*.7.*
%changelog
* Fri May 17 2024 fuanan <fuanan3@h-partners.com> - 2.43.0-4
- Type:CVE
- ID:CVE-2024-32021 CVE-2024-32004 CVE-2024-32020 CVE-2024-32465
- SUG:NA
- DESC:Fix CVE-2024-32021 CVE-2024-32004 CVE-2024-32020 CVE-2024-32465
* Wed May 15 2024 qiaojijun <qiaojijun@kylinos.cn> - 2.43.0-3
- Type:CVE
- ID:CVE-2024-32002