When cloning a repository with `--local`, Git relies on either making a
hardlink or copy to every file in the "objects" directory of the source
repository. This is done through the callpath `cmd_clone()` ->
`clone_local()` -> `copy_or_link_directory()`.
The way this optimization works is by enumerating every file and
directory recursively in the source repository's `$GIT_DIR/objects`
directory, and then either making a copy or hardlink of each file. The
only exception to this rule is when copying the "alternates" file, in
which case paths are rewritten to be absolute before writing a new
"alternates" file in the destination repo.
One quirk of this implementation is that it dereferences symlinks when
cloning. This behavior was most recently modified in 36596fd2df (clone:
better handle symlinked files at .git/objects/, 2019-07-10), which
attempted to support `--local` clones of repositories with symlinks in
their objects directory in a platform-independent way.
Unfortunately, this behavior of dereferencing symlinks (that is,
creating a hardlink or copy of the source's link target in the
destination repository) can be used as a component in attacking a
victim by inadvertently exposing the contents of file stored outside of
the repository.
Take, for example, a repository that stores a Dockerfile and is used to
build Docker images. When building an image, Docker copies the directory
contents into the VM, and then instructs the VM to execute the
Dockerfile at the root of the copied directory. This protects against
directory traversal attacks by copying symbolic links as-is without
dereferencing them.
That is, if a user has a symlink pointing at their private key material
(where the symlink is present in the same directory as the Dockerfile,
but the key itself is present outside of that directory), the key is
unreadable to a Docker image, since the link will appear broken from the
container's point of view.
This behavior enables an attack whereby a victim is convinced to clone a
repository containing an embedded submodule (with a URL like
"file:///proc/self/cwd/path/to/submodule") which has a symlink pointing
at a path containing sensitive information on the victim's machine. If a
user is tricked into doing this, the contents at the destination of
those symbolic links are exposed to the Docker image at runtime.
One approach to preventing this behavior is to recreate symlinks in the
destination repository. But this is problematic, since symlinking the
objects directory are not well-supported. (One potential problem is that
when sharing, e.g. a "pack" directory via symlinks, different writers
performing garbage collection may consider different sets of objects to
be reachable, enabling a situation whereby garbage collecting one
repository may remove reachable objects in another repository).
Instead, prohibit the local clone optimization when any symlinks are
present in the `$GIT_DIR/objects` directory of the source repository.
Users may clone the repository again by prepending the "file://" scheme
to their clone URL, or by adding the `--no-local` option to their `git
clone` invocation.
The directory iterator used by `copy_or_link_directory()` must no longer
dereference symlinks (i.e., it *must* call `lstat()` instead of `stat()`
in order to discover whether or not there are symlinks present). This has
no bearing on the overall behavior, since we will immediately `die()` on
encounter a symlink.
Note that t5604.33 suggests that we do support local clones with
symbolic links in the source repository's objects directory, but this
was likely unintentional, or at least did not take into consideration
the problem with sharing parts of the objects directory with symbolic
links at the time. Update this test to reflect which options are and
aren't supported.
Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Fix a regression in 2.35 that roke the use of "rebase" and "stash"
in a secondary worktree.
* en/keep-cwd:
sequencer, stash: fix running from worktree subdir
In commits bc3ae46b42 ("rebase: do not attempt to remove
startup_info->original_cwd", 2021-12-09) and 0fce211ccc ("stash: do not
attempt to remove startup_info->original_cwd", 2021-12-09), we wanted to
allow the subprocess to know which directory the parent process was
running from, so that the subprocess could protect it. However...
When run from a non-main worktree, setup_git_directory() will note
that the discovered git directory
(/PATH/TO/.git/worktree/non-main-worktree) does not match
DEFAULT_GIT_DIR_ENVIRONMENT (see setup_discovered_git_dir()), and
decide to set GIT_DIR in the environment. This matters because...
Whenever git is run with the GIT_DIR environment variable set, and
GIT_WORK_TREE not set, it presumes that '.' is the working tree. So...
This combination results in the subcommand being very confused about
the working tree. Fix it by also setting the GIT_WORK_TREE environment
variable along with setting cmd.dir.
A possibly more involved fix we could consider for later would be to
make setup.c set GIT_WORK_TREE whenever (a) it discovers both the git
directory and the working tree and (b) it decides to set GIT_DIR in the
environment. I did not attempt that here as such would be too big of a
change for a 2.35.1 release.
Test-case-by: Glen Choo <chooglen@google.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We added an unrelated sanity checking that leads to a BUG() while
plugging a leak, which triggered in a repository with symrefs in
the local branch namespace that point at a ref outside. Partially
revert the change to avoid triggering the BUG().
* ab/checkout-branch-info-leakfix:
checkout: avoid BUG() when hitting a broken repository
When 9081a421 (checkout: fix "branch info" memory leaks, 2021-11-16)
cleaned up existing memory leaks, we added an unrelated sanity check
to ensure that a local branch is truly local and not a symref to
elsewhere that dies with BUG() otherwise. This was misguided in two
ways. First of all, such a tightening did not belong to a leak-fix
patch. And the condition it detected was *not* a bug in our program
but a problem in user data, where warning() or die() would have been
more appropriate.
As the condition is not fatal (the result of computing the local
branch name in the code that is involved in the faulty check is only
used as a textual label for the commit), let's revert the code to
the original state, i.e. strip "refs/heads/" to compute the local
branch name if possible, and otherwise leave it NULL. The consumer
of the information in merge_working_tree() is prepared to see NULL
in there and act accordingly.
cf. https://bugzilla.redhat.com/show_bug.cgi?id=2042920
Reported-by: Petr Šplíchal <psplicha@redhat.com>
Reported-by: Todd Zullinger <tmz@pobox.com>
Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git branch -h" incorrectly said "--track[=direct|inherit]",
implying that "--trackinherit" is a valid option, which has been
corrected.
source: <3de40324bea6a1dd9bca2654721471e3809e87d8.1642538935.git.steadmon@google.com>
source: <c3c26192-aee9-185a-e559-b8735139e49c@web.de>
* js/branch-track-inherit:
branch,checkout: fix --track documentation
Document that the accepted variants of the --track option are --track,
--track=direct, and --track=inherit. The equal sign in the latter two
cannot be replaced with whitespace; in general optional arguments need
to be attached firmly to their option.
Put "direct" consistently before "inherit", if only for the reasons
that the former is the default, explained first in the documentation,
and comes before the latter alphabetically.
Mention both modes in the short help so that readers don't have to look
them up in the full documentation. They are literal strings and thus
untranslatable. PARSE_OPT_LITERAL_ARGHELP is inferred due to the pipe
and parenthesis characters, so we don't have to provide that flag
explicitly.
Mention that -t has the same effect as --track and --track=direct.
There is no way to specify inherit mode using the short option, because
short options generally don't accept optional arguments.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git branch -h" incorrectly said "--track[=direct|inherit]",
implying that "--trackinherit" is a valid option, which has been
corrected.
* js/branch-track-inherit:
branch,checkout: fix --track usage strings
As Ævar pointed out in [1], the use of PARSE_OPT_LITERAL_ARGHELP with a
list of allowed parameters is not recommended. Both git-branch and
git-checkout were changed in d311566 (branch: add flags and config to
inherit tracking, 2021-12-20) to use this discouraged combination for
their --track flags.
Fix this by removing PARSE_OPT_LITERAL_ARGHELP, and changing the arghelp
to simply be "mode". Users may discover allowed values in the manual
pages.
[1]: https://lore.kernel.org/git/220111.86a6g3yqf9.gmgdl@evledraar.gmail.com/
Signed-off-by: Josh Steadmon <steadmon@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some lockfile code called free() in signal-death code path, which
has been corrected.
* ps/lockfile-cleanup-fix:
fetch: fix deadlock when cleaning up lockfiles in async signals
"git stash apply" forgot to attempt restoring untracked files when
it failed to restore changes to tracked ones.
* en/stash-df-fix:
stash: do not return before restoring untracked files
Similar message templates have been consolidated so that
translators need to work on fewer number of messages.
* ja/i18n-similar-messages:
i18n: turn even more messages into "cannot be used together" ones
i18n: ref-filter: factorize "%(foo) atom used without %(bar) atom"
i18n: factorize "--foo outside a repository"
i18n: refactor "unrecognized %(foo) argument" strings
i18n: factorize "no directory given for --foo"
i18n: factorize "--foo requires --bar" and the like
i18n: tag.c factorize i18n strings
i18n: standardize "cannot open" and "cannot read"
i18n: turn "options are incompatible" into "cannot be used together"
i18n: refactor "%s, %s and %s are mutually exclusive"
i18n: refactor "foo and bar are mutually exclusive"
"git -c branch.autosetupmerge=inherit branch new old" makes "new"
to have the same upstream as the "old" branch, instead of marking
"old" itself as its upstream.
* js/branch-track-inherit:
config: require lowercase for branch.*.autosetupmerge
branch: add flags and config to inherit tracking
branch: accept multiple upstream branches for tracking
Code clean-up to hide vreportf() from public API.
* ab/usage-die-message:
config API: use get_error_routine(), not vreportf()
usage.c + gc: add and use a die_message_errno()
gc: return from cmd_gc(), don't call exit()
usage.c API users: use die_message() for error() + exit 128
usage.c API users: use die_message() for "fatal :" + exit 128
usage.c: add a die_message() routine
Code refactoring in the reflog part of refs API.
* ab/reflog-prep:
reflog + refs-backend: move "verbose" out of the backend
refs files-backend: assume cb->newlog if !EXPIRE_REFLOGS_DRY_RUN
reflog: reduce scope of "struct rev_info"
reflog expire: don't use lookup_commit_reference_gently()
reflog expire: refactor & use "tip_commit" only for UE_NORMAL
reflog expire: use "switch" over enum values
reflog: change one->many worktree->refnames to use a string_list
reflog expire: narrow scope of "cb" in cmd_reflog_expire()
reflog delete: narrow scope of "cmd" passed to count_reflog_ent()
"git stash" by default triggers its "push" action, but its
implementation also made "git stash -h" to show short help only for
"git stash push", which has been corrected.
* ab/do-not-limit-stash-help-to-push:
stash: don't show "git stash push" usage on bad "git stash" usage
"git fetch" and "git pull" are now declared sparse-index clean.
Also "git ls-files" learns the "--sparse" option to help debugging.
* ds/fetch-pull-with-sparse-index:
test-read-cache: remove --table, --expand options
t1091/t3705: remove 'test-tool read-cache --table'
t1092: replace 'read-cache --table' with 'ls-files --sparse'
ls-files: add --sparse option
fetch/pull: use the sparse index
Use of certain "git rev-list" options with "git fast-export"
created nonsense results (the worst two of which being "--reverse"
and "--invert-grep --grep=<foo>"). The use of "--first-parent" is
made to behave a bit more sensible than before.
* ws/fast-export-with-revision-options:
fast-export: fix surprising behavior with --first-parent
Certain sparse-checkout patterns that are valid in non-cone mode
led to segfault in cone mode, which has been corrected.
* ds/sparse-checkout-malformed-pattern-fix:
sparse-checkout: refuse to add to bad patterns
sparse-checkout: fix OOM error with mixed patterns
sparse-checkout: fix segfault on malformed patterns
When fetching packfiles, we write a bunch of lockfiles for the packfiles
we're writing into the repository. In order to not leave behind any
cruft in case we exit or receive a signal, we register both an exit
handler as well as signal handlers for common signals like SIGINT. These
handlers will then unlink the locks and free the data structure tracking
them. We have observed a deadlock in this logic though:
(gdb) bt
#0 __lll_lock_wait_private () at ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95
#1 0x00007f4932bea2cd in _int_free (av=0x7f4932f2eb20 <main_arena>, p=0x3e3e4200, have_lock=0) at malloc.c:3969
#2 0x00007f4932bee58c in __GI___libc_free (mem=<optimized out>) at malloc.c:2975
#3 0x0000000000662ab1 in string_list_clear ()
#4 0x000000000044f5bc in unlock_pack_on_signal ()
#5 <signal handler called>
#6 _int_free (av=0x7f4932f2eb20 <main_arena>, p=<optimized out>, have_lock=0) at malloc.c:4024
#7 0x00007f4932bee58c in __GI___libc_free (mem=<optimized out>) at malloc.c:2975
#8 0x000000000065afd5 in strbuf_release ()
#9 0x000000000066ddb9 in delete_tempfile ()
#10 0x0000000000610d0b in files_transaction_cleanup.isra ()
#11 0x0000000000611718 in files_transaction_abort ()
#12 0x000000000060d2ef in ref_transaction_abort ()
#13 0x000000000060d441 in ref_transaction_prepare ()
#14 0x000000000060e0b5 in ref_transaction_commit ()
#15 0x00000000004511c2 in fetch_and_consume_refs ()
#16 0x000000000045279a in cmd_fetch ()
#17 0x0000000000407c48 in handle_builtin ()
#18 0x0000000000408df2 in cmd_main ()
#19 0x00000000004078b5 in main ()
The process was killed with a signal, which caused the signal handler to
kick in and try free the data structures after we have unlinked the
locks. It then deadlocks while calling free(3P).
The root cause of this is that it is not allowed to call certain
functions in async-signal handlers, as specified by signal-safety(7).
Next to most I/O functions, this list of disallowed functions also
includes memory-handling functions like malloc(3P) and free(3P) because
they may not be reentrant. As a result, if we execute such functions in
the signal handler, then they may operate on inconistent state and fail
in unexpected ways.
Fix this bug by not calling non-async-signal-safe functions when running
in the signal handler. We're about to re-raise the signal anyway and
will thus exit, so it's not much of a problem to keep the string list of
lockfiles untouched. Note that it's fine though to call unlink(2), so
we'll still clean up the lockfiles correctly.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Reviewed-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The default merge message prepared by "git merge" records the name
of the current branch; the name can be overridden with a new option
to allow users to pretend a merge is made on a different branch.
* jc/merge-detached-head-name:
merge: allow to pretend a merge is made into a different branch
"git am" learns "--empty=(stop|drop|keep)" option to tweak what is
done to a piece of e-mail without a patch in it.
* xw/am-empty:
am: support --allow-empty to record specific empty patches
am: support --empty=<option> to handle empty patches
doc: git-format-patch: describe the option --always
Many git commands that deal with working tree files try to remove a
directory that becomes empty (i.e. "git switch" from a branch that
has the directory to another branch that does not would attempt
remove all files in the directory and the directory itself). This
drops users into an unfamiliar situation if the command was run in
a subdirectory that becomes subject to removal due to the command.
The commands have been taught to keep an empty directory if it is
the directory they were started in to avoid surprising users.
* en/keep-cwd:
t2501: simplify the tests since we can now assume desired behavior
dir: new flag to remove_dir_recurse() to spare the original_cwd
dir: avoid incidentally removing the original_cwd in remove_path()
stash: do not attempt to remove startup_info->original_cwd
rebase: do not attempt to remove startup_info->original_cwd
clean: do not attempt to remove startup_info->original_cwd
symlinks: do not include startup_info->original_cwd in dir removal
unpack-trees: add special cwd handling
unpack-trees: refuse to remove startup_info->original_cwd
setup: introduce startup_info->original_cwd
t2501: add various tests for removing the current working directory
Even if some of these messages are not subject to gettext i18n, this
helps bring a single style of message for a given error type.
Signed-off-by: Jean-Noël Avila <jn.avila@free.fr>
Reviewed-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
They are all replaced by "the option '%s' requires '%s'", which is a
new string but replaces 17 previous unique strings.
Signed-off-by: Jean-Noël Avila <jn.avila@free.fr>
Reviewed-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use placeholders for constant tokens. The strings are turned into
"cannot be used together"
Signed-off-by: Jean-Noël Avila <jn.avila@free.fr>
Reviewed-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use static strings for constant parts of the sentences. They are all
turned into "cannot be used together".
Signed-off-by: Jean-Noël Avila <jn.avila@free.fr>
Reviewed-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In commit bee8691f19 ("stash: restore untracked files AFTER restoring
tracked files", 2021-09-10), we correctly identified that we should
restore changes to tracked files before attempting to restore untracked
files, and accordingly moved the code for restoring untracked files a
few lines down in do_apply_stash(). Unfortunately, the intervening
lines had some early return statements meaning that we suddenly stopped
restoring untracked files in some cases.
Even before the previous commit, there was another possible issue with
the current code -- a post-stash-apply 'git status' that was intended
to be run after restoring the stash was skipped when we hit a conflict
(or other error condition), which seems slightly inconsistent.
Fix both issues by saving the return status, and letting other
functionality run before returning.
Reported-by: AJ Henderson
Test-case-by: Randall S. Becker <randall.becker@nexbridge.ca>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "init" and "set" subcommands in "git sparse-checkout" have been
unified for a better user experience and performance.
* en/sparse-checkout-set:
sparse-checkout: remove stray trailing space
clone: avoid using deprecated `sparse-checkout init`
Documentation: clarify/correct a few sparsity related statements
git-sparse-checkout.txt: update to document init/set/reapply changes
sparse-checkout: enable reapply to take --[no-]{cone,sparse-index}
sparse-checkout: enable `set` to initialize sparse-checkout mode
sparse-checkout: split out code for tweaking settings config
sparse-checkout: disallow --no-stdin as an argument to set
sparse-checkout: add sanity-checks on initial sparsity state
sparse-checkout: break apart functions for sparse_checkout_(set|add)
sparse-checkout: pass use_stdin as a parameter instead of as a global
New interface into the tmp-objdir API to help in-core use of the
quarantine feature.
* ns/tmp-objdir:
tmp-objdir: disable ref updates when replacing the primary odb
tmp-objdir: new API for creating temporary writable databases
"git format-patch" uses a single rev_info instance and then exits.
Mark the structure with UNLEAK() macro to squelch leak sanitizer.
* jc/unleak-log:
format-patch: mark rev_info with UNLEAK
When in cone mode sparse-checkout, it is unclear how 'git
sparse-checkout add <dir1> ...' should behave if the existing
sparse-checkout file does not match the cone mode patterns. Change the
behavior to fail with an error message about the existing patterns.
Also, all cone mode patterns start with a '/' character, so add that
restriction. This is necessary for our example test 'cone mode: warn on
bad pattern', but also requires modifying the example sparse-checkout
file we use to test the warnings related to recognizing cone mode
patterns.
This error checking would cause a failure further down the test script
because of a test that adds non-cone mode patterns without cleaning them
up. Perform that cleanup as part of the test now.
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a test to t1091-sparse-checkout-builtin.sh that would result in an
infinite loop and out-of-memory error before this change. The issue
relies on having non-cone-mode patterns while trying to modify the
patterns in cone-mode.
The fix is simple, allowing us to break from the loop when the input
path does not contain a slash, as the "dir" pattern we added does not.
This is only a fix to the critical out-of-memory error. A better
response to such a strange state will follow in a later change.
Reported-by: Calbabreaker <calbabreaker@gmail.com>
Helped-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git fetch --set-upstream" did not check if there is a current
branch, leading to a segfault when it is run on a detached HEAD,
which has been corrected.
* ab/fetch-set-upstream-while-detached:
pull, fetch: fix segfault in --set-upstream option
Move the handling of the "verbose" flag entirely out of
"refs/files-backend.c" and into "builtin/reflog.c". This allows the
backend to stop knowing about the EXPIRE_REFLOGS_VERBOSE flag.
The expire_reflog_ent() function shouldn't need to deal with the
implementation detail of whether or not we're emitting verbose output,
by doing this the --verbose output becomes backend-agnostic, so
reftable will get the same output.
I think the output is rather bad currently, and should e.g. be
implemented with some better future mode of progress.[ch], but that's
a topic for another improvement.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the "cmd.stalefix" handling added in 1389d9ddaa (reflog expire
--fix-stale, 2007-01-06) to use a locally scoped "struct
rev_info". This code relies on mark_reachable_objects() twiddling
flags in the walked objects.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the initial implementation of "git reflog" in 4264dc15e1 (git
reflog expire, 2006-12-19) we had this
lookup_commit_reference_gently().
I don't think we've ever found tags that we need to recursively
dereference in reflogs, so this should at least be changed to a
"lookup commit" as I'm doing here, although I can't think of a way
where it mattered in practice.
I also think we'd probably like to just die here if we have a NULL
object, but as this code needs to handle potentially broken
repositories let's just show an "error" but continue, the non-quiet
lookup_commit() will do for us. None of our tests cover the case where
"commit" is NULL after this lookup.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add an intermediate variable for "tip_commit" in
reflog_expiry_prepare(), and only add it to the struct if we're
handling the UE_NORMAL case.
The code behaves the same way as before, but this makes the control
flow clearer, and the shorter name allows us to fold a 4-line i/else
into a one-line ternary instead.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change code added in 03cb91b18c (reflog --expire-unreachable: special
case entries in "HEAD" reflog, 2010-04-09) to use a "switch" statement
with an exhaustive list of "case" statements instead of doing numeric
comparisons against the enum labels.
Now we won't assume that "x != UE_ALWAYS" means "(x == UE_HEAD || x ||
UE_NORMAL)". That assumption is true now, but we'd introduce subtle
bugs here if that were to change, now the compiler will notice and
error out on such errors.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the FLEX_ARRAY pattern added in bda3a31cc7 (reflog-expire:
Avoid creating new files in a directory inside readdir(3) loop,
2008-01-25) the string-list API instead.
This does not change any behavior, allows us to delete much of this
code as it's replaced by things we get from the string-list API for
free, as a result we need just one struct to keep track of this data,
instead of two.
The "DUP" -> "string_list_append_nodup(..., strbuf_detach(...))"
pattern here is the same as that used in a recent memory leak fix in
b202e51b15 (grep: fix a "path_list" memory leak, 2021-10-22).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
