* fixes/2.45.1/2.41:
Revert "fsck: warn about symlink pointing inside a gitdir"
Revert "Add a helper function to compare file contents"
clone: drop the protections where hooks aren't run
tests: verify that `clone -c core.hooksPath=/dev/null` works again
Revert "core.hooksPath: add some protection while cloning"
init: use the correct path of the templates directory again
hook: plug a new memory leak
ci: stop installing "gcc-13" for osx-gcc
ci: avoid bare "gcc" for osx-gcc job
ci: drop mention of BREW_INSTALL_PACKAGES variable
send-email: avoid creating more than one Term::ReadLine object
send-email: drop FakeTerm hack
* fixes/2.45.1/2.40:
Revert "fsck: warn about symlink pointing inside a gitdir"
Revert "Add a helper function to compare file contents"
clone: drop the protections where hooks aren't run
tests: verify that `clone -c core.hooksPath=/dev/null` works again
Revert "core.hooksPath: add some protection while cloning"
init: use the correct path of the templates directory again
hook: plug a new memory leak
ci: stop installing "gcc-13" for osx-gcc
ci: avoid bare "gcc" for osx-gcc job
ci: drop mention of BREW_INSTALL_PACKAGES variable
send-email: avoid creating more than one Term::ReadLine object
send-email: drop FakeTerm hack
Revert overly aggressive "layered defence" that went into 2.45.1
and friends, which broke "git-lfs", "git-annex", and other use
cases, so that we can rebuild necessary counterparts in the open.
* jc/fix-2.45.1-and-friends-for-2.39:
Revert "fsck: warn about symlink pointing inside a gitdir"
Revert "Add a helper function to compare file contents"
clone: drop the protections where hooks aren't run
tests: verify that `clone -c core.hooksPath=/dev/null` works again
Revert "core.hooksPath: add some protection while cloning"
init: use the correct path of the templates directory again
hook: plug a new memory leak
ci: stop installing "gcc-13" for osx-gcc
ci: avoid bare "gcc" for osx-gcc job
ci: drop mention of BREW_INSTALL_PACKAGES variable
send-email: avoid creating more than one Term::ReadLine object
send-email: drop FakeTerm hack
As part of the security bug-fix releases v2.39.4, ..., v2.45.1, I
introduced logic to safeguard `git clone` from running hooks that were
installed _during_ the clone operation.
The rationale was that Git's CVE-2024-32002, CVE-2021-21300,
CVE-2019-1354, CVE-2019-1353, CVE-2019-1352, and CVE-2019-1349 should
have been low-severity vulnerabilities but were elevated to
critical/high severity by the attack vector that allows a weakness where
files inside `.git/` can be inadvertently written during a `git clone`
to escalate to a Remote Code Execution attack by virtue of installing a
malicious `post-checkout` hook that Git will then run at the end of the
operation without giving the user a chance to see what code is executed.
Unfortunately, Git LFS uses a similar strategy to install its own
`post-checkout` hook during a `git clone`; In fact, Git LFS is
installing four separate hooks while running the `smudge` filter.
While this pattern is probably in want of being improved by introducing
better support in Git for Git LFS and other tools wishing to register
hooks to be run at various stages of Git's commands, let's undo the
clone protections to unbreak Git LFS-enabled clones.
This reverts commit 8db1e8743c (clone: prevent hooks from running
during a clone, 2024-03-28).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* maint-2.41: (38 commits)
Git 2.41.1
Git 2.40.2
Git 2.39.4
fsck: warn about symlink pointing inside a gitdir
core.hooksPath: add some protection while cloning
init.templateDir: consider this config setting protected
clone: prevent hooks from running during a clone
Add a helper function to compare file contents
init: refactor the template directory discovery into its own function
find_hook(): refactor the `STRIP_EXTENSION` logic
clone: when symbolic links collide with directories, keep the latter
entry: report more colliding paths
t5510: verify that D/F confusion cannot lead to an RCE
submodule: require the submodule path to contain directories only
clone_submodule: avoid using `access()` on directories
submodules: submodule paths must not contain symlinks
clone: prevent clashing git dirs when cloning submodule in parallel
t7423: add tests for symlinked submodule directories
has_dir_name(): do not get confused by characters < '/'
docs: document security issues around untrusted .git dirs
...
* maint-2.40: (39 commits)
Git 2.40.2
Git 2.39.4
fsck: warn about symlink pointing inside a gitdir
core.hooksPath: add some protection while cloning
init.templateDir: consider this config setting protected
clone: prevent hooks from running during a clone
Add a helper function to compare file contents
init: refactor the template directory discovery into its own function
find_hook(): refactor the `STRIP_EXTENSION` logic
clone: when symbolic links collide with directories, keep the latter
entry: report more colliding paths
t5510: verify that D/F confusion cannot lead to an RCE
submodule: require the submodule path to contain directories only
clone_submodule: avoid using `access()` on directories
submodules: submodule paths must not contain symlinks
clone: prevent clashing git dirs when cloning submodule in parallel
t7423: add tests for symlinked submodule directories
has_dir_name(): do not get confused by characters < '/'
docs: document security issues around untrusted .git dirs
upload-pack: disable lazy-fetching by default
...
* maint-2.39: (38 commits)
Git 2.39.4
fsck: warn about symlink pointing inside a gitdir
core.hooksPath: add some protection while cloning
init.templateDir: consider this config setting protected
clone: prevent hooks from running during a clone
Add a helper function to compare file contents
init: refactor the template directory discovery into its own function
find_hook(): refactor the `STRIP_EXTENSION` logic
clone: when symbolic links collide with directories, keep the latter
entry: report more colliding paths
t5510: verify that D/F confusion cannot lead to an RCE
submodule: require the submodule path to contain directories only
clone_submodule: avoid using `access()` on directories
submodules: submodule paths must not contain symlinks
clone: prevent clashing git dirs when cloning submodule in parallel
t7423: add tests for symlinked submodule directories
has_dir_name(): do not get confused by characters < '/'
docs: document security issues around untrusted .git dirs
upload-pack: disable lazy-fetching by default
fetch/clone: detect dubious ownership of local repositories
...
This topic addresses two CVEs:
- CVE-2024-32020:
Local clones may end up hardlinking files into the target repository's
object database when source and target repository reside on the same
disk. If the source repository is owned by a different user, then
those hardlinked files may be rewritten at any point in time by the
untrusted user.
- CVE-2024-32021:
When cloning a local source repository that contains symlinks via the
filesystem, Git may create hardlinks to arbitrary user-readable files
on the same filesystem as the target repository in the objects/
directory.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Critical security issues typically combine relatively common
vulnerabilities such as case confusion in file paths with other
weaknesses in order to raise the severity of the attack.
One such weakness that has haunted the Git project in many a
submodule-related CVE is that any hooks that are found are executed
during a clone operation. Examples are the `post-checkout` and
`fsmonitor` hooks.
However, Git's design calls for hooks to be disabled by default, as only
disabled example hooks are copied over from the templates in
`<prefix>/share/git-core/templates/`.
As a defense-in-depth measure, let's prevent those hooks from running.
Obviously, administrators can choose to drop enabled hooks into the
template directory, though, _and_ it is also possible to override
`core.hooksPath`, in which case the new check needs to be disabled.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We will need to call this function from `hook.c` to be able to prevent
hooks from running that were written as part of a `clone` but did not
originate from the template directory.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Submodules are stored in subdirectories of their superproject. When
these subdirectories have been replaced with symlinks by a malicious
actor, all kinds of mayhem can be caused.
This _should_ not be possible, but many CVEs in the past showed that
_when_ possible, it allows attackers to slip in code that gets executed
during, say, a `git clone --recursive` operation.
Let's add some defense-in-depth to disallow submodule paths to have
anything except directories in them.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In 0060fd1511 (clone --recurse-submodules: prevent name squatting on
Windows, 2019-09-12), I introduced code to verify that a git dir either
does not exist, or is at least empty, to fend off attacks where an
inadvertently (and likely maliciously) pre-populated git dir would be
used while cloning submodules recursively.
The logic used `access(<path>, X_OK)` to verify that a directory exists
before calling `is_empty_dir()` on it. That is a curious way to check
for a directory's existence and might well fail for unwanted reasons.
Even the original author (it was I ;-) ) struggles to explain why this
function was used rather than `stat()`.
This code was _almost_ copypastad in the previous commit, but that
`access()` call was caught during review.
Let's use `stat()` instead also in the code that was almost copied
verbatim. Let's not use `lstat()` because in the unlikely event that
somebody snuck a symbolic link in, pointing to a crafted directory, we
want to verify that that directory is empty.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When creating a submodule path, we must be careful not to follow
symbolic links. Otherwise we may follow a symbolic link pointing to
a gitdir (which are valid symbolic links!) e.g. while cloning.
On case-insensitive filesystems, however, we blindly replace a directory
that has been created as part of the `clone` operation with a symlink
when the path to the latter differs only in case from the former's path.
Let's simply avoid this situation by expecting not ever having to
overwrite any existing file/directory/symlink upon cloning. That way, we
won't even replace a directory that we just created.
This addresses CVE-2024-32002.
Reported-by: Filip Hejsek <filip.hejsek@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
While it is expected to have several git dirs within the `.git/modules/`
tree, it is important that they do not interfere with each other. For
example, if one submodule was called "captain" and another submodule
"captain/hooks", their respective git dirs would clash, as they would be
located in `.git/modules/captain/` and `.git/modules/captain/hooks/`,
respectively, i.e. the latter's files could clash with the actual Git
hooks of the former.
To prevent these clashes, and in particular to prevent hooks from being
written and then executed as part of a recursive clone, we introduced
checks as part of the fix for CVE-2019-1387 in a8dee3ca61 (Disallow
dubiously-nested submodule git directories, 2019-10-01).
It is currently possible to bypass the check for clashing submodule
git dirs in two ways:
1. parallel cloning
2. checkout --recurse-submodules
Let's check not only before, but also after parallel cloning (and before
checking out the submodule), that the git dir is not clashing with
another one, otherwise fail. This addresses the parallel cloning issue.
As to the parallel checkout issue: It requires quite a few manual steps
to create clashing git dirs because Git itself would refuse to
initialize the inner one, as demonstrated by the test case.
Nevertheless, let's teach the recursive checkout (namely, the
`submodule_move_head()` function that is used by the recursive checkout)
to be careful to verify that it does not use a clashing git dir, and if
it does, disable it (by deleting the `HEAD` file so that subsequent Git
calls won't recognize it as a git dir anymore).
Note: The parallel cloning test case contains a `cat err` that proved to
be highly useful when analyzing the racy nature of the operation (the
operation can fail with three different error messages, depending on
timing), and was left on purpose to ease future debugging should the
need arise.
Signed-off-by: Filip Hejsek <filip.hejsek@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
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>
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>
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>
Update "git maintainance" timers' implementation based on systemd
timers to work with WSL.
* js/systemd-timers-wsl-fix:
maintenance(systemd): support the Windows Subsystem for Linux
"git grep -e A --no-or -e B" is accepted, even though the negation
of "or" did not mean anything, which has been tightened.
* rs/grep-no-no-or:
grep: reject --no-or
"git diff --no-such-option" and other corner cases around the exit
status of the "diff" command has been corrected.
* jk/diff-result-code-cleanup:
diff: drop useless "status" parameter from diff_result_code()
diff: drop useless return values in git-diff helpers
diff: drop useless return from run_diff_{files,index} functions
diff: die when failing to read index in git-diff builtin
diff: show usage for unknown builtin_diff_files() options
diff-files: avoid negative exit value
diff: spell DIFF_INDEX_CACHED out when calling run_diff_index()
transfer.unpackLimit ought to be used as a fallback, but overrode
fetch.unpackLimit and receive.unpackLimit instead.
* ts/unpacklimit-config-fix:
transfer.unpackLimit: fetch/receive.unpackLimit takes precedence
These error messages say "new_index" as if that spelling has some
significance to the end users (e.g. the file "$GIT_DIR/new_index"
has some issues), but that is not the case at all. The i18n folks
were made to include the word literally in the translated messages,
which was not a good idea at all. Spell it "new index", as we are
just telling the users that we failed to create a new index file.
The term is expected to be translated to the end-users' languages,
not left as if it were a literal file name.
This dates all the way back to the first re-implemenation of "git
commit" command in C (the scripted version did not have such wording
in its error messages), in f5bbc322 (Port git commit to C.,
2007-11-08).
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As described in the CodingGuidelines document, a single line message
given to die() and its friends should not capitalize its first word,
and should not add full-stop at the end.
Signed-off-by: Naomi Ibe <naomi.ibeh69@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The DESCRIPTION's "first form" is actually the 1st, 2nd, 3rd and 5th
form in SYNOPSIS, the "second form" is the 4th one.
Interestingly, this state of affairs was introduced in
97fe725075 (cat-file docs: fix SYNOPSIS and "-h" output, 2021-12-28)
with the claim of "Now the two will match again." ("the two" being
DESCRIPTION and SYNOPSIS)...
The description also suffers from other correctness and clarity issues,
e.g., the "first form" paragraph discusses -p, -s and -t, but leaves out
-e, which is included in the corresponding SYNOPSIS section; the second
paragraph mentions <format>, which doesn't occur in SYNOPSIS at all, and
of the three batch options, really only describes the behavior of
--batch-check. Also the mention of "drivers" seems an implementation
detail not adding much clarity in a short summary (and isn't expanded
upon in the rest of the man page, either).
Rather than trying to maintain one-to-one (or N-to-M) correspondence
between the DESCRIPTION and SYNOPSIS forms, creating duplication and
providing opportunities for error, shorten the former into a concise
summary describing the two general modes of operation: batch and
non-batch, leaving details to the subsequent manual sections.
While here, fix a grammar error in the description of -e and make the
following further minor improvements:
NAME:
shorten ("content or type and size" isn't the whole story; say
"details" and leave the actual details to later sections)
SYNOPSIS and --help:
move the (--textconv | --filters) form before --batch, closer
to the other non-batch forms
Signed-off-by: Štěpán Němec <stepnem@smrk.net>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The argument order was incorrect. This was introduced by 246cac8505
(i18n: turn even more messages into "cannot be used together" ones,
2022-01-05).
Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When running in the Windows Subsystem for Linux (WSL), it is usually
necessary to use the Git Credential Manager for authentication when
performing the background fetches.
This requires interoperability between the Windows Subsystem for Linux
and the Windows host to work, which uses so-called vsocks, i.e. sockets
intended for communcations between virtual machines and the host they
are running on.
However, when Git is configured to run background maintenance via
`systemd`, the address families available to those maintenance processes
are restricted, and did not include `AF_VSOCK`. This leads to problems
e.g. when a background fetch tries to access github.com:
systemd[437]: Starting Optimize Git repositories data...
git[747387]: WSL (747387) ERROR: UtilBindVsockAnyPort:285: socket failed 97
git[747381]: fatal: could not read Username for 'https://github.com': No such device or address
git[747381]: error: failed to prefetch remotes
git[747381]: error: task 'prefetch' failed
systemd[437]: git-maintenance@hourly.service: Main process exited, code=exited, status=1/FAILURE
systemd[437]: git-maintenance@hourly.service: Failed with result 'exit-code'.
systemd[437]: Failed to start Optimize Git repositories data.
Address this (pun intended) by adding the `AF_VSOCK` address family to
the allow list.
This fixes https://github.com/microsoft/git/issues/604.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since 3e230fa1b2 (grep: use parseopt, 2009-05-07) git grep has been
accepting the option --no-or. It does the same as --or: nothing.
That's confusing and unintended. Forbid negating --or.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The code introduced in 576a37fccb (var: add attributes files locations,
2023-06-27) paid careful attention to use `xstrdup()` for pointers known
never to be `NULL`, and `xstrdup_or_null()` otherwise.
One spot was missed, though: `git_attr_global_file()` can return `NULL`,
when the `HOME` variable is not set (and neither `XDG_CONFIG_HOME`), a
scenario not too uncommon in certain server scenarios.
Fix this, and add a test case to avoid future regressions.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Acked-by: brian m. carlson <bk2204@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
a91f453f64 (grep: Add --max-depth option., 2009-07-22) added the option
--max-depth, defining it using a positional struct option initializer of
type OPTION_INTEGER. It also sets defval to 1 for some reason, but that
value would only be used if the flag PARSE_OPT_OPTARG was given.
Use the macro OPT_INTEGER_F instead to standardize the definition and
specify only the necessary values. This also normalizes argh to N_("n")
as a side-effect, which is OK.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
adfc1857bd (describe: fix --contains when a tag is given as input,
2013-07-18) added the option --peel-tag, defining it using a positional
struct option initializer and a comment indicating that it's intended to
be a hidden OPT_BOOL. 4741edd549 (Remove deprecated OPTION_BOOLEAN for
parsing arguments, 2013-08-03) added the macro OPT_HIDDEN_BOOL, which
allows to express this more succinctly. Use it.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The transfer.unpackLimit configuration variable is documented to be
used only as a fallback value when the more operation-specific
fetch.unpackLimit and receive.unpackLimit variables are not set, but
the implementation had the precedence reversed. Apparently this was
broken since the transfer.unpackLimit was introduced in e28714c5
(Consolidate {receive,fetch}.unpackLimit, 2007-01-24).
Often when documentation and code have diverged for so long, we
prefer to change the documentation instead, to avoid disrupting
users. But doing so would make these weirdly unlike most other
"specific overrides general" config options. And the fact that the
bug has existed for so long without anyone noticing implies to me
that nobody really tries to mix and match them much.
Signed-off-by: Taylor Santiago <taylorsantiago@google.com>
[jc: rewrote the log message, added tests, covered receive-pack as well]
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many programs use diff_result_code() to get a user-visible program exit
code from a diff result (e.g., checking opts.found_changes if
--exit-code was requested).
This function also takes a "status" parameter, which seems at first
glance that it could be used to propagate an error encountered when
computing the diff. But it doesn't work that way:
- negative values are passed through as-is, but are not appropriate as
program exit codes
- when --exit-code or --check is in effect, we _ignore_ the passed-in
status completely. So a failed diff which did not have a chance to
set opts.found_changes would erroneously report "success, no
changes" instead of propagating the error.
After recent cleanups, neither of these bugs is possible to trigger, as
every caller just passes in "0". So rather than fixing them, we can
simply drop the useless parameter instead.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since git-diff has many diff modes, it dispatches to many helpers to
perform each one. But every helper simply returns "0", as it exits
directly if there are serious errors (and options like --exit-code are
handled afterwards). So let's get rid of these useless return values,
which makes the code flow more clear.
There's very little chance that we'd later want to propagate errors
instead of dying immediately. These are all static-local helpers for the
git-diff program implementing its various modes. More "lib-ified" code
would directly call the underlying functions.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Neither of these functions ever returns a value other than zero.
Instead, they expect unrecoverable errors to exit immediately, and
things like "--exit-code" are stored inside the diff_options struct to
be handled later via diff_result_code().
Some callers do check the return values, but many don't bother. Let's
drop the useless return values, which are misleading callers about how
the functions work. This could be seen as a step in the wrong direction,
as we might want to eventually "lib-ify" these to more cleanly return
errors up the stack, in which case we'd have to add the return values
back in. But there are some benefits to doing this now:
1. In the current code, somebody could accidentally add a "return -1"
to one of the functions, which would be erroneously ignored by many
callers. By removing the return code, the compiler can notice the
mismatch and force the developer to decide what to do.
Obviously the other option here is that we could start consistently
checking the error code in every caller. But it would be dead code,
and we wouldn't get any compile-time help in catching new cases.
2. It communicates the situation to callers, who may want to choose a
different function. These functions are really thin wrappers for
doing git-diff-files and git-diff-index within the process. But
callers who care about recovering from an error here are probably
better off using the underlying library functions, many of
which do return errors.
If somebody eventually wants to teach these functions to propagate
errors, they'll have to switch back to returning a value, effectively
reverting this patch. But at least then they will be starting with a
level playing field: they know that they will need to inspect each
caller to see how it should handle the error.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the git-diff program fails to read the index in its diff-files or
diff-index helper functions, it propagates the error up the stack. This
eventually lands in diff_result_code(), which does not handle it well
(as discussed in the previous patch).
Since the only sensible thing here is to exit with an error code (and
what we were expecting the propagated error code to cause), let's just
do that directly.
There's no test here, as I'm not even sure this case can be triggered.
The index-reading functions tend to die() themselves when encountering
any errors, and the return value is just the number of entries in the
file (and so always 0 or positive). But let's err on the conservative
side and keep checking the return value. It may be worth digging into as
a separate topic (though index-reading is low-level enough that we
probably want to eventually teach it to propagate errors anyway for
lib-ification purposes, at which point this code would already be doing
the right thing).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The git-diff command has many modes (comparing worktree to index, index
to HEAD, individual blobs, etc). As a result, it dispatches to many
helper functions and cannot completely parse its options until we're in
those helper functions.
Most of them, when seeing an unknown option, exit immediately by calling
usage(). But builtin_diff_files(), which is the default if no revision
or blob arguments are given, instead prints an error() and returns -1.
One obvious shortcoming here is that the user doesn't get to see the
usual usage message. But there's a much more important bug: the -1
return is fed to diff_result_code(), which is not ready to handle it.
By default, it passes the code along as an exit code. We try to avoid
negative exit codes because they get converted to unsigned values, but
it should at least consistently show up as non-zero (i.e., a failure).
But much worse is that when --exit-code is in effect, diff_result_code()
will _ignore_ the status passed in by the caller, and instead only
report on whether the diff found changes. It didn't, of course, because
we never ran the diff, and the program unexpectedly exits with success!
We can fix this bug by just calling usage(), like the other helpers do.
Another option would of course be to teach diff_result_code() to handle
this value. But as we'll see in the next few patches, it can be cleaned
up even further. Let's just fix this bug directly to start with.
Reported-by: Romain Chossart <romainchossart@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If loading the index fails, we print an error and then return "-1" from
the function. But since this is a builtin, we end up with exit(-1),
which produces odd results since program exit codes are unsigned.
Because of integer conversion, it usually becomes 255, which is at least
still an error, but values above 128 are usually interpreted as signal
death.
Since we know the program is exiting immediately, we can just replace
the error return with a die().
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many callers of run_diff_index() passed literal "1" for the option
flag word, which should better be spelled out as DIFF_INDEX_CACHED
for readablity. Everybody else passes "0" that can stay as-is.
The other bit in the option flag word is DIFF_INDEX_MERGE_BASE, but
curiously there is only one caller that can pass it, which is "git
diff-index --merge-base" itself---no internal callers uses the
feature.
A bit tricky call to the function is in builtin/submodule--helper.c
where the .cached member in a private struct is set/reset as a plain
Boolean flag, which happens to be "1" and happens to match the value
of DIFF_INDEX_CACHED.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We switched the function interface for fsck callbacks in a1aad71601
(fsck.h: use "enum object_type" instead of "int", 2021-03-28). However,
we accidentally flipped the type back to "int" as part of 0b4e9013f1
(fsck: mark unused parameters in various fsck callbacks, 2023-07-03).
The mistake happened because that commit was written before a1aad71601
and rebased forward, and I screwed up while resolving the conflict.
Curiously, the compiler does not warn about this mismatch, at least not
when using gcc and clang on Linux (nor in any of our CI environments).
Based on 28abf260a5 (builtin/fsck.c: don't conflate "int" and "enum" in
callback, 2021-06-01), I'd guess that this would cause the AIX xlc
compiler to complain. I noticed because clang-18's UBSan now identifies
mis-matched function calls at runtime, and does complain of this case
when running the test suite.
I'm not entirely clear on whether this mismatch is a problem in
practice. Compilers are certainly free to make enums smaller than "int"
if they don't need the bits, but I suspect that they have to promote
back to int for function calls (though I didn't dig in the standard, and
I won't be surprised if I'm simply wrong and the real-world impact would
depend on the ABI).
Regardless, switching it back to enum is obviously the right thing to do
here; the switch to "int" was simply a mistake.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
