There is a known social engineering attack that takes advantage of the
fact that a working tree can include an entire bare repository,
including a config file. A user could run a Git command inside the bare
repository thinking that the config file of the 'outer' repository would
be used, but in reality, the bare repository's config file (which is
attacker-controlled) is used, which may result in arbitrary code
execution. See [1] for a fuller description and deeper discussion.
A simple mitigation is to forbid bare repositories unless specified via
`--git-dir` or `GIT_DIR`. In environments that don't use bare
repositories, this would be minimally disruptive.
Create a config variable, `safe.bareRepository`, that tells Git whether
or not to die() when working with a bare repository. This config is an
enum of:
- "all": allow all bare repositories (this is the default)
- "explicit": only allow bare repositories specified via --git-dir
or GIT_DIR.
If we want to protect users from such attacks by default, neither value
will suffice - "all" provides no protection, but "explicit" is
impractical for bare repository users. A more usable default would be to
allow only non-embedded bare repositories ([2] contains one such
proposal), but detecting if a repository is embedded is potentially
non-trivial, so this work is not implemented in this series.
[1]: https://lore.kernel.org/git/kl6lsfqpygsj.fsf@chooglen-macbookpro.roam.corp.google.com
[2]: https://lore.kernel.org/git/5b969c5e-e802-c447-ad25-6acc0b784582@github.com
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use git_protected_config() to read `safe.directory` instead of
read_very_early_config(), making it 'protected configuration only'.
As a result, `safe.directory` now respects "-c", so update the tests and
docs accordingly. It used to ignore "-c" due to how it was implemented,
not because of security or correctness concerns [1].
[1] https://lore.kernel.org/git/xmqqlevabcsu.fsf@gitster.g/
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
For security reasons, there are config variables that are only trusted
when they are specified in certain configuration scopes, which are
sometimes referred to on-list as 'protected configuration' [1]. A future
commit will introduce another such variable, so let's define our terms
so that we can have consistent documentation and implementation.
In our documentation, define 'protected configuration' as the system,
global and command config scopes. As a shorthand, I will refer to
variables that are only respected in protected configuration as
'protected configuration only', but this term is not used in the
documentation.
This definition of protected configuration is based on whether or not
Git can reasonably protect the user by ignoring the configuration scope:
- System, global and command line config are considered protected
because an attacker who has control over any of those can do plenty of
harm without Git, so we gain very little by ignoring those scopes.
- On the other hand, local (and similarly, worktree) config are not
considered protected because it is relatively easy for an attacker to
control local config, e.g.:
- On some shared user environments, a non-admin attacker can create a
repository high up the directory hierarchy (e.g. C:\.git on
Windows), and a user may accidentally use it when their PS1
automatically invokes "git" commands.
`safe.directory` prevents attacks of this form by making sure that
the user intended to use the shared repository. It obviously
shouldn't be read from the repository, because that would end up
trusting the repository that Git was supposed to reject.
- "git upload-pack" is expected to run in repositories that may not be
controlled by the user. We cannot ignore all config in that
repository (because "git upload-pack" would fail), but we can limit
the risks by ignoring `uploadpack.packObjectsHook`.
Only `uploadpack.packObjectsHook` is 'protected configuration only'. The
following variables are intentionally excluded:
- `safe.directory` should be 'protected configuration only', but it does
not technically fit the definition because it is not respected in the
"command" scope. A future commit will fix this.
- `trace2.*` happens to read the same scopes as `safe.directory` because
they share an implementation. However, this is not for security
reasons; it is because we want to start tracing so early that
repository-level config and "-c" are not available [2].
This requirement is unique to `trace2.*`, so it does not makes sense
for protected configuration to be subject to the same constraints.
[1] For example,
https://lore.kernel.org/git/6af83767-576b-75c4-c778-0284344a8fe7@github.com/
[2] https://lore.kernel.org/git/a0c89d0d-669e-bf56-25d2-cbb09b012e70@jeffhostetler.com/
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a subsequent commit, we will introduce "protected configuration",
which is easiest to describe in terms of configuration scopes (i.e. it's
the union of the 'system', 'global', and 'command' scopes). This
description is fine for ML discussions, but it's inadequate for end
users because we don't provide a good description of "configuration
scopes" in the public docs.
145d59f482 (config: add '--show-scope' to print the scope of a config
value, 2020-02-10) introduced the word "scope" to our public docs, but
that only enumerates the scopes and assumes the user can figure out
what those values mean.
Add a SCOPES section to Documentation/git-config.txt that describes the
configuration scopes, their corresponding CLI options, and mentions that
some configuration options are only respected in certain scopes. Then,
use the word "scope" to simplify the FILES section and change some
confusing wording.
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
References to commands-to-be-typed-literally in "git rebase"
documentation mark-up have been corrected.
* ds/git-rebase-doc-markup:
git-rebase.txt: use back-ticks consistently
"git push" sometimes perform poorly when reachability bitmaps are
used, even in a repository where other operations are helped by
bitmaps. The push.useBitmaps configuration variable is introduced
to allow disabling use of reachability bitmaps only for "git push".
* zk/push-use-bitmaps:
send-pack.c: add config push.useBitmaps
Teach "git archive" to (optionally and then by default) avoid
spawning an external "gzip" process when creating ".tar.gz" (and
".tgz") archives.
* rs/archive-with-internal-gzip:
archive-tar: use internal gzip by default
archive-tar: use OS_CODE 3 (Unix) for internal gzip
archive-tar: add internal gzip implementation
archive-tar: factor out write_block()
archive: rename archiver data field to filter_command
archive: update format documentation
Adjust technical/bitmap-format to be formatted by AsciiDoc, and
add some missing information to the documentation.
* ac/bitmap-format-doc:
bitmap-format.txt: add information for trailing checksum
bitmap-format.txt: fix some formatting issues
bitmap-format.txt: feed the file to asciidoc to generate html
Update "git diff/log --raw" format documentation.
* pb/diff-doc-raw-format:
diff-index.txt: update raw output format in examples
diff-format.txt: correct misleading wording
diff-format.txt: dst can be 0* SHA-1 when path is deleted, too
While inspecting the 'git rebase' documentation, I noticed that it is
inconsistent with how it uses back-ticks (or other punctuation) for
identifying Git commands, command-line arguments, or values for those
arguments.
Sometimes, an argument (like '--interactive') would appear without any
punctuation, causing the argument to not have any special formatting.
Other times, arguments or 'git rebase' itself would have single-quotes
giving a bold look (in the HTML documentation at least).
By consistently using back-ticks, these types of strings appear in a
monospace font with special highlighting to appear more clearly as text
that exists in a command-line invocation of a Git command.
This rather-large diff is the result of scanning git-rebase.txt and
adding back-ticks as appropriate. Some are adding back-ticks where there
was no punctuation. Others are replacing single quotes.
There are also a few minor cleanups in the process, including those
found by reviewers.
Helped-by: Phillip Wood <phillip.wood123@gmail.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
43966ab315 (revert: optionally refer to commit in the "reference"
format, 2022-05-26) added the documentation file config/revert.txt.
Actually include it in config.txt.
Make is used with a bare infinitive after the object; remove the "to".
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 7281c196b1 (transfer doc: move fetch.credentialsInUrl to
"transfer" config namespace, 2022-06-15) propagates a typo from
6dcbdc0d66 (remote: create fetch.credentialsInUrl config, 2022-06-06),
where "other" is misspelled as "oher". Fix the typo accordingly.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The documentation explained the conversion from remote branch path to
local tracking ref path for @{push}, but not for @{upstream}.
Add the explanation to @{upstream}, and reference it in @{push} to avoid
undue repetition.
Signed-off-by: Tao Klerks <tao@klerks.biz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* maint-2.35:
Git 2.35.4
Git 2.34.4
Git 2.33.4
Git 2.32.3
Git 2.31.4
Git 2.30.5
setup: tighten ownership checks post CVE-2022-24765
git-compat-util: allow root to access both SUDO_UID and root owned
t0034: add negative tests and allow git init to mostly work under sudo
git-compat-util: avoid failing dir ownership checks if running privileged
t: regression git needs safe.directory when using sudo
* maint-2.34:
Git 2.34.4
Git 2.33.4
Git 2.32.3
Git 2.31.4
Git 2.30.5
setup: tighten ownership checks post CVE-2022-24765
git-compat-util: allow root to access both SUDO_UID and root owned
t0034: add negative tests and allow git init to mostly work under sudo
git-compat-util: avoid failing dir ownership checks if running privileged
t: regression git needs safe.directory when using sudo
* maint-2.33:
Git 2.33.4
Git 2.32.3
Git 2.31.4
Git 2.30.5
setup: tighten ownership checks post CVE-2022-24765
git-compat-util: allow root to access both SUDO_UID and root owned
t0034: add negative tests and allow git init to mostly work under sudo
git-compat-util: avoid failing dir ownership checks if running privileged
t: regression git needs safe.directory when using sudo
* maint-2.32:
Git 2.32.3
Git 2.31.4
Git 2.30.5
setup: tighten ownership checks post CVE-2022-24765
git-compat-util: allow root to access both SUDO_UID and root owned
t0034: add negative tests and allow git init to mostly work under sudo
git-compat-util: avoid failing dir ownership checks if running privileged
t: regression git needs safe.directory when using sudo
* maint-2.31:
Git 2.31.4
Git 2.30.5
setup: tighten ownership checks post CVE-2022-24765
git-compat-util: allow root to access both SUDO_UID and root owned
t0034: add negative tests and allow git init to mostly work under sudo
git-compat-util: avoid failing dir ownership checks if running privileged
t: regression git needs safe.directory when using sudo
* maint-2.30:
Git 2.30.5
setup: tighten ownership checks post CVE-2022-24765
git-compat-util: allow root to access both SUDO_UID and root owned
t0034: add negative tests and allow git init to mostly work under sudo
git-compat-util: avoid failing dir ownership checks if running privileged
t: regression git needs safe.directory when using sudo
In asciidoc's HTML output of the "gitrevisions" and "git-rev-parse"
documentation, the header:
The ... (three-dot) Symmetric Difference Notation
is rendered using "&8230;", a horizontal ellipsis. This is visually
ugly, but also hard to search for or cut-and-paste. We really mean three
ascii dots (0x2e) here, so let's make sure it renders as such.
The simplest way to do that is just escaping the leading dot, as the
instances in the rest of the section do. Arguably this should all be
converted to use backticks, which would let us drop the quoting here and
elsewhere (e.g., {carat}). But that does change the rendering slightly.
So let's fix the bug first, and we can decide on migrating the whole
section separately.
Note that this produces an empty doc-diff of the manpages. Curiously,
asciidoc produces the same ellipsis entity in the XML file, but docbook
then converts it back into three literal dots for the roff output! So
the roff manpages have been correct all along (which may be a reason
nobody noticed this until now).
Reported-by: Arthur Milchior
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This patch adds a command line option analogous to that of GNU
grep(1)'s -m / --max-count, which users might already be used to.
This makes it possible to limit the amount of matches shown in the
output while keeping the functionality of other options such as -C
(show code context) or -p (show containing function), which would be
difficult to do with a shell pipeline (e.g. head(1)).
Signed-off-by: Carlos López 00xc@protonmail.com
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"sudo git foo" used to consider a repository owned by the original
user a safe one to access; it now also considers a repository owned
by root a safe one, too (after all, if an attacker can craft a
malicious repository owned by root, the box is 0wned already).
* cb/path-owner-check-with-sudo-plus:
git-compat-util: allow root to access both SUDO_UID and root owned
Reachability bitmaps are designed to speed up the "counting objects"
phase of generating a pack during a clone or fetch. They are not
optimized for Git clients sending a small topic branch via "git push".
In some cases (see [1]), using reachability bitmaps during "git push"
can cause significant performance regressions.
Add a new "push.useBitmaps" configuration variable to allow users to
tell "git push" not to use bitmaps. We already have "pack.bitmaps"
that controls the use of bitmaps, but a separate configuration variable
allows the reachability bitmaps to still be used in other areas,
such as "git upload-pack", while disabling it only for "git push".
[1]: https://lore.kernel.org/git/87zhoz8b9o.fsf@evledraar.gmail.com/
Signed-off-by: Kyle Zhao <kylezhao@tencent.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Previous changes introduced a regression which will prevent root for
accessing repositories owned by thyself if using sudo because SUDO_UID
takes precedence.
Loosen that restriction by allowing root to access repositories owned
by both uid by default and without having to add a safe.directory
exception.
A previous workaround that was documented in the tests is no longer
needed so it has been removed together with its specially crafted
prerequisite.
Helped-by: Johanness Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some config variables are combinations of multiple words, and we
typically write them in camelCase forms in manpage and translatable
strings. It's not easy to find mismatches for these camelCase config
variables during code reviews, but occasionally they are identified
during localization translations.
To check for mismatched config variables, I introduced a new feature
in the helper program for localization[^1]. The following mismatched
config variables have been identified by running the helper program,
such as "git-po-helper check-pot".
Lowercase in manpage should use camelCase:
* Documentation/config/http.txt: http.pinnedpubkey
Lowercase in translable strings should use camelCase:
* builtin/fast-import.c: pack.indexversion
* builtin/gc.c: gc.logexpiry
* builtin/index-pack.c: pack.indexversion
* builtin/pack-objects.c: pack.indexversion
* builtin/repack.c: pack.writebitmaps
* commit.c: i18n.commitencoding
* gpg-interface.c: user.signingkey
* http.c: http.postbuffer
* submodule-config.c: submodule.fetchjobs
Mismatched camelCases, choose the former:
* Documentation/config/transfer.txt: transfer.credentialsInUrl
remote.c: transfer.credentialsInURL
[^1]: https://github.com/git-l10n/git-po-helper
Signed-off-by: Jiang Xin <zhiyou.jx@alibaba-inc.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Rename fetch.credentialsInUrl to transfer.credentialsInUrl as the
single configuration variable should work both in pushing and
fetching.
* ab/credentials-in-url-more:
transfer doc: move fetch.credentialsInUrl to "transfer" config namespace
fetch doc: note "pushurl" caveat about "credentialsInUrl", elaborate
Bitmap file has a trailing checksum at the end of the file. However
there is no information in the bitmap-format documentation about it.
Add a trailer section to include the trailing checksum info in the
`Documentation/technical/bitmap-format.txt` file.
Signed-off-by: Abhradeep Chakraborty <chakrabortyabhradeep79@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The asciidoc generated html for `Documentation/technical/bitmap-
format.txt` is broken. This is mainly because `-` is used for nested
lists (which is not allowed in asciidoc) instead of `*`.
Fix these and also reformat it for better readability of the html page.
Signed-off-by: Abhradeep Chakraborty <chakrabortyabhradeep79@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
