Many memory leaks in the sparse-checkout code paths have been
plugged.
* jk/sparse-leakfix:
sparse-checkout: free duplicate hashmap entries
sparse-checkout: free string list after displaying
sparse-checkout: free pattern list in sparse_checkout_list()
sparse-checkout: free sparse_filename after use
sparse-checkout: refactor temporary sparse_checkout_patterns
sparse-checkout: always free "line" strbuf after reading input
sparse-checkout: reuse --stdin buffer when reading patterns
dir.c: always copy input to add_pattern()
dir.c: free removed sparse-pattern hashmap entries
sparse-checkout: clear patterns when init() sees existing sparse file
dir.c: free strings in sparse cone pattern hashmaps
sparse-checkout: pass string literals directly to add_pattern()
sparse-checkout: free string list in write_cone_to_file()
An overly large ".gitignore" files are now rejected silently.
* jk/cap-exclude-file-size:
dir.c: reduce max pattern file size to 100MB
dir.c: skip .gitignore, etc larger than INT_MAX
The safe.directory configuration knob has been updated to
optionally allow leading path matches.
* jc/safe-directory-leading-path:
safe.directory: allow "lead/ing/path/*" match
A pair of test helpers that essentially are unit tests on hash
algorithms have been rewritten using the unit-tests framework.
* gt/t-hash-unit-test:
t/: migrate helper/test-{sha1, sha256} to unit-tests/t-hash
strbuf: introduce strbuf_addstrings() to repeatedly add a string
Basic unit tests for reftable have been reimplemented under the
unit test framework.
* cp/reftable-unit-test:
t: improve the test-case for parse_names()
t: add test for put_be16()
t: move tests from reftable/record_test.c to the new unit test
t: move tests from reftable/stack_test.c to the new unit test
t: move reftable/basics_test.c to the unit testing framework
A new test was added to ensure git commands that are designed to
run outside repositories do work.
* jc/t1517-more:
imap-send: minimum leakfix
t1517: more coverage for commands that work without repository
Memory leaks in "git mv" has been plugged.
* jk/leakfixes:
mv: replace src_dir with a strvec
mv: factor out empty src_dir removal
mv: move src_dir cleanup to end of cmd_mv()
t-strvec: mark variable-arg helper with LAST_ARG_MUST_BE_NULL
t-strvec: use va_end() to match va_start()
The alias-expanded command lines are logged to the trace output.
* iw/trace-argv-on-alias:
run-command: show prepared command
Documentation: alias: add notes on shell expansion
Documentation: alias: rework notes into points
Code clean-up around writing the .midx files.
* tb/midx-write-cleanup:
pack-bitmap.c: reimplement `midx_bitmap_filename()` with helper
midx: replace `get_midx_rev_filename()` with a generic helper
midx-write.c: support reading an existing MIDX with `packs_to_include`
midx-write.c: extract `fill_packs_from_midx()`
midx-write.c: extract `should_include_pack()`
midx-write.c: pass `start_pack` to `compute_sorted_entries()`
midx-write.c: reduce argument count for `get_sorted_entries()`
midx-write.c: tolerate `--preferred-pack` without bitmaps
The promisor.quiet configuration knob can be set to true to make
lazy fetching from promisor remotes silent.
* th/quiet-lazy-fetch-from-promisor:
promisor-remote: add promisor.quiet configuration option
Leakfixes.
* ps/leakfixes:
builtin/mv: fix leaks for submodule gitfile paths
builtin/mv: refactor to use `struct strvec`
builtin/mv duplicate string list memory
builtin/mv: refactor `add_slash()` to always return allocated strings
strvec: add functions to replace and remove strings
submodule: fix leaking memory for submodule entries
commit-reach: fix memory leak in `ahead_behind()`
builtin/credential: clear credential before exit
config: plug various memory leaks
config: clarify memory ownership in `git_config_string()`
builtin/log: stop using globals for format config
builtin/log: stop using globals for log config
convert: refactor code to clarify ownership of check_roundtrip_encoding
diff: refactor code to clarify memory ownership of prefixes
config: clarify memory ownership in `git_config_pathname()`
http: refactor code to clarify memory ownership
checkout: clarify memory ownership in `unique_tracking_name()`
strbuf: fix leak when `appendwholeline()` fails with EOF
transport-helper: fix leaking helper name
In insert_recursive_pattern(), we create a new pattern_entry to insert
into the parent_hashmap. If we find that the same entry already exists
in the hashmap, we skip adding the new one. But we forget to free the new
one, creating a leak.
We can fix it by cleaning up the discarded entry. It would probably be
possible to avoid creating it in the first place, but it's non-trivial.
We'd have to define a "keydata" struct that lets us compare the existing
entries to the broken-out fields. It's probably not worth the
complexity, so we'll punt on that for now.
There is one subtlety here: our insertion is happening in a loop, with
each iteration looking at the pattern we just inserted (hence the
"recursive" in the name). So if we skip insertion, what do we look at?
The obvious answer is that we should remember the existing duplicate we
found and use that. But I _think_ in that case, we probably already have
all of the recursive bits already (from when the original entry was
added). And so just breaking out of the loop would be correct. But I'm
not 100% sure on that; after all, the original leaky code could have
done the same break, but it didn't.
So I went with the "obvious answer" above, which has no chance of
changing the behavior aside from fixing the leak.
With this patch, t1091 can now be marked leak-free.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In sparse_checkout_list(), we put the hashmap entries into a string_list
so we can sort them. But after printing, we forget to free the list.
This patch drops 5 leaks from t1091.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In sparse_checkout_list(), we create a pattern_list that needs to
eventually be cleared. We remember to do so in the regular code path,
but the cone-mode path does an early return, and forgets to clean up.
We could fix the leak by adding a new call to clear_pattern_list(). But
we can simplify even further by just skipping the early return, pushing
the other code path (which consists now of only one line!) into an else
block. That also matches the same cone/non-cone if/else used in some
other functions.
This fixes 15 leaks found in t1091.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We allocate a heap buffer via get_sparse_checkout_filename(). Most calls
remember to free it, but sparse_checkout_init() forgets to, causing a
leak. Ironically, it remembers to do so in the error return paths, but
not in the path that makes it all the way to the function end!
Fixing this clears up 6 leaks from t1091.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In update_working_directory(), we take in a pattern_list, attach it to
the repository index by assigning it to index->sparse_checkout_patterns,
and then call unpack_trees. Afterwards, we remove it by setting
index->sparse_checkout_patterns back to NULL.
But there are two possible leaks here:
1. If the index already had a populated sparse_checkout_patterns,
we've obliterated it. We can fix this by saving and restoring it,
rather than always setting it back to NULL.
2. We may call the function with a NULL pattern_list, expecting it to
use the on-disk sparse file. In that case, the index routines will
lazy-load the sparse patterns automatically. But now at the end of
the function when we restore the patterns, we'll leak those
lazy-loaded ones!
We can fix this by freeing the pattern list before overwriting its
pointer whenever it does not match what was passed in (in practice
this should only happen when the passed-in list is NULL, but this
is erring on the defensive side).
Together these remove 48 indirect leaks found in t1091.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In add_patterns_from_input(), we may read lines from a file with a loop
like this:
while (!strbuf_getline(&line, file)) {
...
strbuf_to_cone_pattern(&line, pl);
}
/* we don't strbuf_release(&line) here! */
This generally is OK because strbuf_to_cone_pattern() consumes the
buffer via strbuf_detach(). But we can leak in a few cases:
1. We don't always consume the buffer! If the line ends up empty after
trimming, we leave strbuf_to_cone_pattern() without detaching. In
most cases this is OK, because a subsequent getline() call will use
the same buffer. But if you had an empty line at the end of file,
for example, it would leak.
2. Even if strbuf_to_cone_pattern() always consumed the buffer,
there's a subtle issue with strbuf_getline(). As we saw in
94e2aa555e (strbuf: fix leak when `appendwholeline()` fails with
EOF, 2024-05-27), it's possible for it to return EOF with an
allocated buffer (e.g., if the underlying getdelim() call saw an
error). So we should always strbuf_release() after finishing a read
loop like this.
Note that even the code to read patterns from argv has the same problem.
Because that also uses strbuf_to_cone_pattern(), we stuff each argv
entry into a strbuf. It uses the same "line" strbuf as the getline code,
but we should position the strbuf_release() to cover both code paths.
This fixes at least 9 leaks found in t1091.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we read patterns from --stdin, we loop on strbuf_getline(), and
detach each line we read to pass into add_pattern(). This used to be
necessary because add_pattern() required that the pattern strings remain
valid while the pattern_list was in use. But it also created a leak,
since we didn't record the detached buffers anywhere else.
Now that add_pattern() has been modified to make its own copy of the
strings, we can stop detaching and fix the leak. This fixes 4 leaks
detected in t1091.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The add_pattern() function has a subtle and undocumented gotcha: the
pattern string you pass in must remain valid as long as the pattern_list
is in use (and nor do we take ownership of it). This is easy to get
wrong, causing either subtle bugs (because you free or reuse the string
buffer) or leaks (because you copy the string, but don't track ownership
separately).
All of this "pattern" code was originally the "exclude" mechanism. So
this _usually_ works OK because you add entries in one of two ways:
1. From the command-line (e.g., "--exclude"), in which case we're
pointing to an argv entry which remains valid for the lifetime of
the program.
2. From a file (e.g., ".gitignore"), in which case we read the whole
file into a buffer, attach it to the pattern_list's "filebuf"
entry, then parse the buffer in-place (adding NULs). The strings
point into the filebuf, which is cleaned up when the whole
pattern_list goes away.
But other code, like sparse-checkout, reads individual lines from stdin
and passes them one by one to add_pattern(), leaking each. We could fix
this by refactoring it to take in the whole buffer at once, like (2)
above, and stuff it in "filebuf". But given how subtle the interface is,
let's just fix it to always copy the string.
That seems at first like we'd be wasting extra memory, but we can
mitigate that:
a. The path_pattern struct already uses a FLEXPTR, since we sometimes
make a copy (when we see "foo/", we strip off the trailing slash,
requiring a modifiable copy of the string).
Since we'll now always embed the string inside the struct, we can
switch to the regular FLEX_ARRAY pattern, saving us 8 bytes of
pointer. So patterns with a trailing slash and ones under 8 bytes
actually get smaller.
b. Now that we don't need the original string to hang around, we can
get rid of the "filebuf" mechanism entirely, and just free the file
contents after parsing. Since files are the sources we'd expect to
have the largest pattern sets, we should mostly break even on
stuffing the same data into the individual structs.
This patch just adjusts the add_pattern() interface; it doesn't fix any
leaky callers yet.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a2bc523e1e (dir.c: skip .gitignore, etc larger than INT_MAX,
2024-05-31) we put capped the size of some files whose parsing code and
data structures used ints. Setting the limit to INT_MAX was a natural
spot, since we know the parsing code would misbehave above that.
But it also leaves the possibility of overflow errors when we multiply
that limit to allocate memory. For instance, a file consisting only of
"a\na\n..." could have INT_MAX/2 entries. Allocating an array of
pointers for each would need INT_MAX*4 bytes on a 64-bit system, enough
to overflow a 32-bit int.
So let's give ourselves a bit more safety margin by giving a much
smaller limit. The size 100MB is somewhat arbitrary, but is based on the
similar value for attribute files added by 3c50032ff5 (attr: ignore
overly large gitattributes files, 2022-12-01).
There's no particular reason these have to be the same, but the idea is
that they are in the ballpark of "so huge that nobody would care, but
small enough to avoid malicious overflow". So lacking a better guess, it
makes sense to use the same value. The implementation here doesn't share
the same constant, but we could change that later (or even give it a
runtime config knob, though nobody has complained yet about the
attribute limit).
And likewise, let's add a few tests that exercise the limits, based on
the attr ones. In this case, though, we never read .gitignore from the
index; the blob code is exercised only for sparse filters. So we'll
trigger it that way.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
EVen with the minimum "no-op" invocation t1517 makes, "git imap-send"
leaks an empty strbuf it used to read a 0-byte string into.
There are a few other topics cooking in 'next' that plugs many
other leaks in this program, so let's minimally fix this one, barely
enough to make CI pass, leaving the rest for the other topic.
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In add_pattern_to_hashsets(), we remove entries from the
recursive_hashmap when adding similar ones to the parent_hashmap. I
won't pretend to understand all of what's going on here, but there's an
obvious leak: whatever we removed from recursive_hashmap is not
referenced anywhere else, and is never free()d.
We can easily fix this by asking the hashmap to return a pointer to the
old entry. This makes t7002 now completely leak-free.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In sparse_checkout_init(), we first try to load patterns from an
existing file. If we found any, we return immediately, but end up
leaking the patterns we parsed. Fixing this reduces the number of leaks
in t7002 from 9 down to 5.
Note that there are two other exits from the function, but they don't
need the same treatment:
- if we can't resolve HEAD, we write out a hard-coded sparse file and
return. But we know the pattern list is empty there, since we didn't
find any in the on-disk file and we haven't yet added any of our
own.
- otherwise, we do populate the list and then tail-call into
write_patterns_and_update(). But that function frees the
pattern_list itself, so we don't need to.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The pattern_list structs used for cone-mode sparse lookups use a few
extra hashmaps. These store pattern_entry structs, each of which has its
own heap-allocated pattern string. When we clean up the hashmaps, we
free the individual pattern_entry structs, but forget to clean up the
embedded strings, causing memory leaks.
We can fix this by iterating over the hashmaps to free the extra
strings. This reduces the numbers of leaks in t7002 from 22 to 9.
One alternative here would be to make the string a FLEX_ARRAY member of
the pattern_entry. Then there's no extra free() required, and as a bonus
it would be a little more efficient. However, some of the refactoring
gets awkward, as we are often assigning strings allocated by helper
functions. So let's just fix the leak for now, and we can explore bigger
refactoring separately.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The add_pattern() function takes a pattern string, but neither makes a
copy of it nor takes ownership of the memory. So it is the caller's
responsibility to make sure the string hangs around as long as the
pattern_list which references it.
There are a few cases in sparse-checkout where we use string literal
patterns by stuffing them into a strbuf, detaching the buffer, and then
passing the result into add_pattern(). This creates a leak when the
pattern_list is eventually cleared, since we don't retain a copy of the
detached buffer to free.
But we can observe that the whole strbuf dance is unnecessary. The point
was presumably[1] to satisfy the lifetime requirement of the string. But
string literals have static duration; we can count on them lasting for
the whole program.
So we can fix the leak by just passing them directly. And as a bonus,
that simplifies the code. The leaks can be seen in t7002, which drops
from 25 leaks to 22 with this patch. It also makes t3602 and t1090
leak-free.
In the long run, we will also want to clean up this (undocumented!)
memory lifetime requirement of add_pattern(). But that can come in a
later patch; passing the string literals directly will be the right
thing either way.
[1] The code in question comes from 416adc8711 (sparse-checkout: update
working directory in-process for 'init', 2019-11-21) and 99dfa6f970
(sparse-checkout: use in-process update for disable subcommand,
2019-11-21), but I didn't see anything in their commit messages or
on the list explaining the strbufs.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We use a string list to hold sorted and de-duped patterns, but don't
free it before leaving the function, causing a leak.
This drops the number of leaks found in t7002 from 27 to 25.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When "git push" notices that the commit at the tip of the ref on
the other side it is about to overwrite does not exist locally, it
used to first try fetching it if the local repository is a partial
clone. The command has been taught not to do so and immediately
fail instead.
* th/push-local-ff-check-without-lazy-fetch:
push: don't fetch commit object when checking existence
"git init" in an already created directory, when the user
configuration has includeif.onbranch, started to fail recently,
which has been corrected.
* ps/fix-reinit-includeif-onbranch:
setup: fix bug with "includeIf.onbranch" when initializing dir
This adds a trace point in start_command so we can see the full
command invocation without having to resort to strace/code inspection.
For example:
$ GIT_TRACE=1 git test foo
git.c:755 trace: exec: git-test foo
run-command.c:657 trace: run_command: git-test foo
run-command.c:657 trace: run_command: 'echo $*' foo
run-command.c:749 trace: start_command: /bin/sh -c 'echo $* "$@"' 'echo $*' foo
Prior changes have made the documentation around the internals of the
alias command execution clearer, but I have still found this detailed
view of the aliased command being run helpful for debugging purposes.
A test case is added to ensure the full command output is present in
the execution flow.
Signed-off-by: Ian Wienand <iwienand@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When writing inline shell for shell-expansion aliases (i.e. prefixed
with "!"), there are some caveats around argument parsing to be aware
of. This series of notes attempts to explain what is happening more
clearly.
Signed-off-by: Ian Wienand <iwienand@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We use add_patterns() to read .gitignore, .git/info/exclude, etc, as
well as other pattern-like files like sparse-checkout. The parser for
these uses an "int" as an index, meaning that files over 2GB will
generally cause signed integer overflow and out-of-bounds access.
This is unlikely to happen in any real files, but we do read .gitignore
files from the tree. A malicious tree could cause an out-of-bounds read
and segfault (we also write NULs over newlines, so in theory it could be
an out-of-bounds write, too, but as we go char-by-char, the first thing
that happens is trying to read a negative 2GB offset).
We could fix the most obvious issue by replacing one "int" with a
"size_t". But there are tons of "int" sprinkled throughout this code for
things like pattern lengths, number of patterns, and so on. Since nobody
would actually want a 2GB .gitignore file, an easy defensive measure is
to just refuse to parse them.
The "int" in question is in add_patterns_from_buffer(), so we could
catch it there. But by putting the checks in its two callers, we can
produce more useful error messages.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge down a handful of topics to adjust tests and CI to make them
work better, without changing Git itself, and a bit of developer
docs update:
* Tests that try to corrupt in-repository files in chunked format did
not work well on macOS due to its broken "mv", which has been
worked around.
* Unbreak CI jobs so that we do not attempt to use Python 2 that has
been removed from the platform.
* Git 2.43 started using the tree of HEAD as the source of attributes
in a bare repository, which has severe performance implications.
For now, revert the change, without ripping out a more explicit
support for the attr.tree configuration variable.
* Windows CI running in GitHub Actions started complaining about the
order of arguments given to calloc(); the imported regex code uses
the wrong order almost consistently, which has been corrected.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
CI fix.
* jk/ci-macos-gcc13-fix:
ci: stop installing "gcc-13" for osx-gcc
ci: avoid bare "gcc" for osx-gcc job
ci: drop mention of BREW_INSTALL_PACKAGES variable
The SubmittingPatches document now refers folks to manpages
translation project.
* jc/doc-manpages-l10n:
SubmittingPatches: advertise git-manpages-l10n project a bit
Windows CI running in GitHub Actions started complaining about the
order of arguments given to calloc(); the imported regex code uses
the wrong order almost consistently, which has been corrected.
* jc/compat-regex-calloc-fix:
compat/regex: fix argument order to calloc(3)
Git 2.43 started using the tree of HEAD as the source of attributes
in a bare repository, which has severe performance implications.
For now, revert the change, without ripping out a more explicit
support for the attr.tree configuration variable.
* jc/no-default-attr-tree-in-bare:
stop using HEAD for attributes in bare repository by default
Unbreak CI jobs so that we do not attempt to use Python 2 that has
been removed from the platform.
* ps/ci-python-2-deprecation:
ci: fix Python dependency on Ubuntu 24.04
Tests that try to corrupt in-repository files in chunked format did
not work well on macOS due to its broken "mv", which has been
worked around.
* jc/test-workaround-broken-mv:
t/lib-chunk: work around broken "mv" on some vintage of macOS
* jk/leakfixes:
mv: replace src_dir with a strvec
mv: factor out empty src_dir removal
mv: move src_dir cleanup to end of cmd_mv()
t-strvec: mark variable-arg helper with LAST_ARG_MUST_BE_NULL
t-strvec: use va_end() to match va_start()
While most of the commands in Git suite are designed to do useful
things in Git repositories, some commands are also usable outside
any repository. Building on top of an earlier work abece6e9 (t1517:
test commands that are designed to be run outside repository,
2024-05-20) that adds tests for such commands, let's give coverage
to some more commands.
This patch covers commands whose code has hits for
$ git grep setup_git_directory_gently
and passes a pointer to nongit_ok variable it uses to allow it to
run outside a Git repository, but mostly they are tested only to see
that they start up (as opposed to dying with "not in a git
repository" complaint). We may want to update them to actually do
something useful later, but this would at least help us catch
regressions by mistake.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
