Translation for Simplified Chinese.#3
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jiangxin merged 1 commit intogit-l10n:masterfrom Feb 28, 2012
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Signed-off-by: Jiang Xin <worldhello.net@gmail.com>
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Amended this merge commit with a update commit log.
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In 41c21f2 (branch.c: Validate tracking branches with refspecs instead of refs/remotes/*), we changed the rules for what is considered a valid tracking branch (a.k.a. upstream branch). We now use the configured remotes and their refspecs to determine whether a proposed tracking branch is in fact within the domain of a remote, and we then use that information to deduce the upstream configuration (branch.<name>.remote and branch.<name>.merge). However, with that change, we also check that - in addition to a matching refspec - the result of mapping the tracking branch through that refspec (i.e. the corresponding ref name in the remote repo) happens to start with "refs/heads/". In other words, we require that a tracking branch refers to a _branch_ in the remote repo. Now, consider that you are e.g. setting up an automated building/testing infrastructure for a group of similar "source" repositories. The build/test infrastructure consists of a central scheduler, and a number of build/test "slave" machines that perform the actual build/test work. The scheduler monitors the group of similar repos for changes (e.g. with a periodic "git fetch"), and triggers builds/tests to be run on one or more slaves. Graphically the changes flow between the repos like this: Source #1 -------v ----> Slave #1 / Source #2 -----> Scheduler -----> Slave #2 \ Source #3 -------^ ----> Slave #3 ... ... The scheduler maintains a single Git repo with each of the source repos set up as distinct remotes. The slaves also need access to all the changes from all of the source repos, so they pull from the scheduler repo, but using the following custom refspec: remote.origin.fetch = "+refs/remotes/*:refs/remotes/*" This makes all of the scheduler's remote-tracking branches automatically available as identical remote-tracking branches in each of the slaves. Now, consider what happens if a slave tries to create a local branch with one of the remote-tracking branches as upstream: git branch local_branch --track refs/remotes/source-1/some_branch Git now looks at the configured remotes (in this case there is only "origin", pointing to the scheduler's repo) and sees refs/remotes/source-1/some_branch matching origin's refspec. Mapping through that refspec we find that the corresponding remote ref name is "refs/remotes/source-1/some_branch". However, since this remote ref name does not start with "refs/heads/", we discard it as a suitable upstream, and the whole command fails. This patch adds a testcase demonstrating this failure by creating two source repos ("a" and "b") that are forwarded through a scheduler ("c") to a slave repo ("d"), that then tries create a local branch with an upstream. See the next patch in this series for the exciting conclusion to this story... Reported-by: Per Cederqvist <cederp@opera.com> Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Suppose a fetch or push is requested between two shallow repositories (with no history deepening or shortening). A pack that contains necessary objects is transferred over together with .git/shallow of the sender. The receiver has to determine whether it needs to update .git/shallow if new refs needs new shallow comits. The rule here is avoid updating .git/shallow by default. But we don't want to waste the received pack. If the pack contains two refs, one needs new shallow commits installed in .git/shallow and one does not, we keep the latter and reject/warn about the former. Even if .git/shallow update is allowed, we only add shallow commits strictly necessary for the former ref (remember the sender can send more shallow commits than necessary) and pay attention not to accidentally cut the receiver history short (no history shortening is asked for) So the steps to figure out what ref need what new shallow commits are: 1. Split the sender shallow commit list into "ours" and "theirs" list by has_sha1_file. Those that exist in current repo in "ours", the remaining in "theirs". 2. Check the receiver .git/shallow, remove from "ours" the ones that also exist in .git/shallow. 3. Fetch the new pack. Either install or unpack it. 4. Do has_sha1_file on "theirs" list again. Drop the ones that fail has_sha1_file. Obviously the new pack does not need them. 5. If the pack is kept, remove from "ours" the ones that do not exist in the new pack. 6. Walk the new refs to answer the question "what shallow commits, both ours and theirs, are required in .git/shallow in order to add this ref?". Shallow commits not associated to any refs are removed from their respective list. 7. (*) Check reachability (from the current refs) of all remaining commits in "ours". Those reachable are removed. We do not want to cut any part of our (reachable) history. We only check up commits. True reachability test is done by check_everything_connected() at the end as usual. 8. Combine the final "ours" and "theirs" and add them all to .git/shallow. Install new refs. The case where some hook rejects some refs on a push is explained in more detail in the push patches. Of these steps, #6 and #7 are expensive. Both require walking through some commits, or in the worst case all commits. And we rather avoid them in at least common case, where the transferred pack does not contain any shallow commits that the sender advertises. Let's look at each scenario: 1) the sender has longer history than the receiver All shallow commits from the sender will be put into "theirs" list at step 1 because none of them exists in current repo. In the common case, "theirs" becomes empty at step 4 and exit early. 2) the sender has shorter history than the receiver All shallow commits from the sender are likely in "ours" list at step 1. In the common case, if the new pack is kept, we could empty "ours" and exit early at step 5. If the pack is not kept, we hit the expensive step 6 then exit after "ours" is emptied. There'll be only a handful of objects to walk in fast-forward case. If it's forced update, we may need to walk to the bottom. 3) the sender has same .git/shallow as the receiver This is similar to case 2 except that "ours" should be emptied at step 2 and exit early. A fetch after "clone --depth=X" is case 1. A fetch after "clone" (from a shallow repo) is case 3. Luckily they're cheap for the common case. A push from "clone --depth=X" falls into case 2, which is expensive. Some more work may be done at the sender/client side to avoid more work on the server side: if the transferred pack does not contain any shallow commits, send-pack should not send any shallow commits to the receive-pack, effectively turning it into a normal push and avoid all steps. This patch implements all steps except #3, already handled by fetch-pack and receive-pack, #6 and #7, which has their own patch due to their size. (*) in previous versions step 7 was put before step 3. I reorder it so that the common case that keeps the pack does not need to walk commits at all. In future if we implement faster commit reachability check (maybe with the help of pack bitmaps or commit cache), step 7 could become cheap and be moved up before 6 again. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Apr 19, 2014
ja-po: Add Japanese translations
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Use write_script. The resulting patch makes it a lot easier to understand what the written script is doing. Signed-off-by: Junio C Hamano <gitster@pobox.com>
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gitster
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Signed-off-by: Junio C Hamano <gitster@pobox.com>
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The collect_parents() function now is responsible for
1. parsing the commits given on the command line into a list of
commits to be merged;
2. filtering these parents into independent ones; and
3. optionally calling fmt_merge_msg() via prepare_merge_message()
to prepare an auto-generated merge log message, using fake
contents that FETCH_HEAD would have had if these commits were
fetched from the current repository with "git pull . $args..."
Make "git merge FETCH_HEAD" to be the same as the traditional
git merge "$(git fmt-merge-msg <.git/FETCH_HEAD)" $commits
invocation of the command in "git pull", where $commits are the ones
that appear in FETCH_HEAD that are not marked as not-for-merge, by
making it do a bit more, specifically:
- noticing "FETCH_HEAD" is the only "commit" on the command line
and picking the commits that are not marked as not-for-merge as
the list of commits to be merged (substitute for step #1 above);
- letting the resulting list fed to step #2 above;
- doing the step #3 above, using the contents of the FETCH_HEAD
instead of fake contents crafted from the list of commits parsed
in the step #1 above.
Note that this changes the semantics. "git merge FETCH_HEAD" has
always behaved as if the first commit in the FETCH_HEAD file were
directly specified on the command line, creating a two-way merge
whose auto-generated merge log said "merge commit xyz". With this
change, if the previous fetch was to grab multiple branches (e.g.
"git fetch $there topic-a topic-b"), the new world order is to
create an octopus, behaving as if "git pull $there topic-a topic-b"
were run. This is a deliberate change to make that happen, and
can be seen in the changes to t3033 tests.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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A "rebase" replays changes of the local branch on top of something else, as such they are placed in stage #3 and referred to as "theirs", while the changes in the new base, typically a foreign work, are placed in stage #2 and referred to as "ours". Clarify the "checkout --ours/--theirs". * se/doc-checkout-ours-theirs: checkout: document subtlety around --ours/--theirs
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A "rebase" replays changes of the local branch on top of something else, as such they are placed in stage #3 and referred to as "theirs", while the changes in the new base, typically a foreign work, are placed in stage #2 and referred to as "ours". Clarify the "checkout --ours/--theirs". * se/doc-checkout-ours-theirs: checkout: document subtlety around --ours/--theirs
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When ac49f5c (rerere "remaining", 2011-02-16) split out a new helper function check_one_conflict() out of find_conflict() function, so that the latter will use the returned value from the new helper to update the loop control variable that is an index into active_cache[], the new variable incremented the index by one too many when it found a path with only stage #1 entry at the very end of active_cache[]. This "strange" return value does not have any effect on the loop control of two callers of this function, as they all notice that active_nr+2 is larger than active_nr just like active_nr+1 is, but nevertheless it puzzles the readers when they are trying to figure out what the function is trying to do. In fact, there is no need to do an early return. The code that follows after skipping the stage #1 entry is fully prepared to handle a case where the entry is at the very end of active_cache[]. Help future readers from unnecessary confusion by dropping an early return. We skip the stage #1 entry, and if there are stage #2 and stage #3 entries for the same path, we diagnose the path as THREE_STAGED (otherwise we say PUNTED), and then we skip all entries for the same path. Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Jul 15, 2017
We turn off ASan's leak detection by default in the test
suite because it's too noisy. But we don't do so until
part-way through test-lib. This is before we've run any
tests, but after we do our initial "./git" to see if the
binary has even been built.
When built with clang, this seems to work fine. However,
using "gcc -fsanitize=address", the leak checker seems to
complain more aggressively:
$ ./git
...
==5352==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 2 byte(s) in 1 object(s) allocated from:
#0 0x7f120e7afcf8 in malloc (/usr/lib/x86_64-linux-gnu/libasan.so.3+0xc1cf8)
#1 0x559fc2a3ce41 in do_xmalloc /home/peff/compile/git/wrapper.c:60
#2 0x559fc2a3cf1a in do_xmallocz /home/peff/compile/git/wrapper.c:100
#3 0x559fc2a3d0ad in xmallocz /home/peff/compile/git/wrapper.c:108
#4 0x559fc2a3d0ad in xmemdupz /home/peff/compile/git/wrapper.c:124
#5 0x559fc2a3d0ad in xstrndup /home/peff/compile/git/wrapper.c:130
#6 0x559fc274535a in main /home/peff/compile/git/common-main.c:39
#7 0x7f120dabd2b0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202b0)
This is a leak in the sense that we never free it, but it's
in a global that is meant to last the whole program. So it's
not really interesting or in need of fixing. And at any
rate, mentioning leaks outside of the test_expect blocks is
certainly unwelcome, as it pollutes stderr.
Let's bump the setting of ASAN_OPTIONS higher in test-lib.sh
to catch our initial "can we even run git?" test. While
we're at it, we can add a comment to make it a bit less
inscrutable.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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This is to address concerns raised by ThreadSanitizer on the mailing list about threaded unprotected R/W access to map.size with my previous "disallow rehash" change (0607e10). See: https://public-inbox.org/git/adb37b70139fd1e2bac18bfd22c8b96683ae18eb.1502780344.git.martin.agren@gmail.com/ Add API to hashmap to disable item counting and thus automatic rehashing. Also include API to later re-enable them. When item counting is disabled, the map.size field is invalid. So to prevent accidents, the field has been renamed and an accessor function hashmap_get_size() has been added. All direct references to this field have been been updated. And the name of the field changed to map.private_size to communicate this. Here is the relevant output from ThreadSanitizer showing the problem: WARNING: ThreadSanitizer: data race (pid=10554) Read of size 4 at 0x00000082d488 by thread T2 (mutexes: write M16): #0 hashmap_add hashmap.c:209 #1 hash_dir_entry_with_parent_and_prefix name-hash.c:302 #2 handle_range_dir name-hash.c:347 #3 handle_range_1 name-hash.c:415 #4 lazy_dir_thread_proc name-hash.c:471 #5 <null> <null> Previous write of size 4 at 0x00000082d488 by thread T1 (mutexes: write M31): #0 hashmap_add hashmap.c:209 #1 hash_dir_entry_with_parent_and_prefix name-hash.c:302 #2 handle_range_dir name-hash.c:347 #3 handle_range_1 name-hash.c:415 #4 handle_range_dir name-hash.c:380 #5 handle_range_1 name-hash.c:415 #6 lazy_dir_thread_proc name-hash.c:471 #7 <null> <null> Martin gives instructions for running TSan on test t3008 in this post: https://public-inbox.org/git/CAN0heSoJDL9pWELD6ciLTmWf-a=oyxe4EXXOmCKvsG5MSuzxsA@mail.gmail.com/ Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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The function ce_write_entry() uses a 'self-initialised' variable
construct, for the symbol 'saved_namelen', to suppress a gcc
'-Wmaybe-uninitialized' warning, given that the warning is a false
positive.
For the purposes of this discussion, the ce_write_entry() function has
three code blocks of interest, that look like so:
/* block #1 */
if (ce->ce_flags & CE_STRIP_NAME) {
saved_namelen = ce_namelen(ce);
ce->ce_namelen = 0;
}
/* block #2 */
/*
* several code blocks that contain, among others, calls
* to copy_cache_entry_to_ondisk(ondisk, ce);
*/
/* block #3 */
if (ce->ce_flags & CE_STRIP_NAME) {
ce->ce_namelen = saved_namelen;
ce->ce_flags &= ~CE_STRIP_NAME;
}
The warning implies that gcc thinks it is possible that the first
block is not entered, the calls to copy_cache_entry_to_ondisk()
could toggle the CE_STRIP_NAME flag on, thereby entering block #3
with saved_namelen unset. However, the copy_cache_entry_to_ondisk()
function does not write to ce->ce_flags (it only reads). gcc could
easily determine this, since that function is local to this file,
but it obviously doesn't.
In order to suppress this warning, we make it clear to the reader
(human and compiler), that block #3 will only be entered when the
first block has been entered, by introducing a new 'stripped_name'
boolean variable. We also take the opportunity to change the type
of 'saved_namelen' to 'unsigned int' to match ce->ce_namelen.
Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
ruester
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Signed-off-by: Matthias Rüster <matthias.ruester@gmail.com>
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…ev()
In 'builtin/name-rev.c' in the name_rev() function there is a loop
iterating over all parents of the given commit, and the loop body
looks like this:
if (parent_number > 1) {
if (generation > 0)
// branch #1
new_name = ...
else
// branch #2
new_name = ...
name_rev(parent, new_name, ...);
} else {
// branch #3
name_rev(...);
}
These conditions are not covered properly in the test suite. As far
as purely test coverage goes, they are all executed several times over
in 't6120-describe.sh'. However, they don't directly influence the
command's output, because the repository used in that test script
contains several branches and tags pointing somewhere into the middle
of the commit DAG, and thus result in a better name for the
to-be-named commit. This can hide bugs: e.g. by replacing the
'new_name' parameter of the first recursive name_rev() call with
'tip_name' (effectively making both branch #1 and #2 a noop) 'git
name-rev --all' shows thousands of bogus names in the Git repository,
but the whole test suite still passes successfully. In an early
version of a later patch in this series I managed to mess up all three
branches (at once!), but the test suite still passed.
So add a new test case that operates on the following history:
A--------------master
\ /
\----------M2
\ /
\---M1-C
\ /
B
and names the commit 'B' to make sure that all three branches are
crucial to determine 'B's name:
- There is only a single ref, so all names are based on 'master',
without any undesired interference from other refs.
- Each time name_rev() follows the second parent of a merge commit,
it appends "^2" to the name. Following 'master's second parent
right at the start ensures that all commits on the ancestry path
from 'master' to 'B' have a different base name from the original
'tip_name' of the very first name_rev() invocation. Currently,
while name_rev() is recursive, it doesn't matter, but it will be
necessary to properly cover all three branches after the recursion
is eliminated later in this series.
- Following 'M2's second parent makes sure that branch #2 (i.e. when
'generation = 0') affects 'B's name.
- Following the only parent of the non-merge commit 'C' ensures that
branch #3 affects 'B's name, and that it increments 'generation'.
- Coming from 'C' 'generation' is 1, thus following 'M1's second
parent makes sure that branch #1 affects 'B's name.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Recent versions of the gcc and clang Address Sanitizer produce test
failures related to regexec(). This triggers with gcc-10 and clang-8
(but not gcc-9 nor clang-7). Running:
make CC=gcc-10 SANITIZE=address test
results in failures in t4018, t3206, and t4062.
The cause seems to be that when built with ASan, we use a different
version of regexec() than normal. And this version doesn't understand
the REG_STARTEND flag. Here's my evidence supporting that.
The failure in t4062 is an ASan warning:
expecting success of 4062.2 '-G matches':
git diff --name-only -G "^(0{64}){64}$" HEAD^ >out &&
test 4096-zeroes.txt = "$(cat out)"
=================================================================
==672994==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7fa76f672000 at pc 0x7fa7726f75b6 bp 0x7ffe41bdda70 sp 0x7ffe41bdd220
READ of size 4097 at 0x7fa76f672000 thread T0
#0 0x7fa7726f75b5 (/lib/x86_64-linux-gnu/libasan.so.6+0x4f5b5)
#1 0x562ae0c9c40e in regexec_buf /home/peff/compile/git/git-compat-util.h:1117
#2 0x562ae0c9c40e in diff_grep /home/peff/compile/git/diffcore-pickaxe.c:52
#3 0x562ae0c9cc28 in pickaxe_match /home/peff/compile/git/diffcore-pickaxe.c:166
[...]
In this case we're looking in a buffer which was mmap'd via
reuse_worktree_file(), and whose size is 4096 bytes. But libasan's
regex tries to look at byte 4097 anyway! If we tweak Git like this:
diff --git a/diff.c b/diff.c
index 8e2914c..cfae60c120 100644
--- a/diff.c
+++ b/diff.c
@@ -3880,7 +3880,7 @@ static int reuse_worktree_file(struct index_state *istate,
*/
if (ce_uptodate(ce) ||
(!lstat(name, &st) && !ie_match_stat(istate, ce, &st, 0)))
- return 1;
+ return 0;
return 0;
}
to use a regular buffer (with a trailing NUL) instead of an mmap, then
the complaint goes away.
The other failures are actually diff output with an incorrect funcname
header. If I instrument xdiff to show the funcname matching like so:
diff --git a/xdiff-interface.c b/xdiff-interface.c
index 8509f9e..f6c3dc1986 100644
--- a/xdiff-interface.c
+++ b/xdiff-interface.c
@@ -197,6 +197,7 @@ struct ff_regs {
struct ff_reg {
regex_t re;
int negate;
+ char *printable;
} *array;
};
@@ -218,7 +219,12 @@ static long ff_regexp(const char *line, long len,
for (i = 0; i < regs->nr; i++) {
struct ff_reg *reg = regs->array + i;
- if (!regexec_buf(®->re, line, len, 2, pmatch, 0)) {
+ int ret = regexec_buf(®->re, line, len, 2, pmatch, 0);
+ warning("regexec %s:\n regex: %s\n buf: %.*s",
+ ret == 0 ? "matched" : "did not match",
+ reg->printable,
+ (int)len, line);
+ if (!ret) {
if (reg->negate)
return -1;
break;
@@ -264,6 +270,7 @@ void xdiff_set_find_func(xdemitconf_t *xecfg, const char *value, int cflags)
expression = value;
if (regcomp(®->re, expression, cflags))
die("Invalid regexp to look for hunk header: %s", expression);
+ reg->printable = xstrdup(expression);
free(buffer);
value = ep + 1;
}
then when compiling with ASan and gcc-10, running the diff from t4018.66
produces this:
$ git diff -U1 cpp-skip-access-specifiers
warning: regexec did not match:
regex: ^[ ]*[A-Za-z_][A-Za-z_0-9]*:[[:space:]]*($|/[/*])
buf: private:
warning: regexec matched:
regex: ^((::[[:space:]]*)?[A-Za-z_].*)$
buf: private:
diff --git a/cpp-skip-access-specifiers b/cpp-skip-access-specifiers
index 4d4a9db..ebd6f42 100644
--- a/cpp-skip-access-specifiers
+++ b/cpp-skip-access-specifiers
@@ -6,3 +6,3 @@ private:
void DoSomething();
int ChangeMe;
};
void DoSomething();
- int ChangeMe;
+ int IWasChanged;
};
That first regex should match (and is negated, so it should be telling
us _not_ to match "private:"). But it wouldn't if regexec() is looking
at the whole buffer, and not just the length-limited line we've fed to
regexec_buf(). So this is consistent again with REG_STARTEND being
ignored.
The correct output (compiling without ASan, or gcc-9 with Asan) looks
like this:
warning: regexec matched:
regex: ^[ ]*[A-Za-z_][A-Za-z_0-9]*:[[:space:]]*($|/[/*])
buf: private:
[...more lines that we end up not using...]
warning: regexec matched:
regex: ^((::[[:space:]]*)?[A-Za-z_].*)$
buf: class RIGHT : public Baseclass
diff --git a/cpp-skip-access-specifiers b/cpp-skip-access-specifiers
index 4d4a9db..ebd6f42 100644
--- a/cpp-skip-access-specifiers
+++ b/cpp-skip-access-specifiers
@@ -6,3 +6,3 @@ class RIGHT : public Baseclass
void DoSomething();
- int ChangeMe;
+ int IWasChanged;
};
So it really does seem like libasan's regex engine is ignoring
REG_STARTEND. We should be able to work around it by compiling with
NO_REGEX, which would use our local regexec(). But to make matters even
more interesting, this isn't enough by itself.
Because ASan has support from the compiler, it doesn't seem to intercept
our call to regexec() at the dynamic library level. It actually
recognizes when we are compiling a call to regexec() and replaces it
with ASan-specific code at that point. And unlike most of our other
compat code, where we might have git_mmap() or similar, the actual
symbol name in the compiled compat/regex code is regexec(). So just
compiling with NO_REGEX isn't enough; we still end up in libasan!
We can work around that by having the preprocessor replace regexec with
git_regexec (both in the callers and in the actual implementation), and
we truly end up with a call to our custom regex code, even when
compiling with ASan. That's probably a good thing to do anyway, as it
means anybody looking at the symbols later (e.g., in a debugger) would
have a better indication of which function is which. So we'll do the
same for the other common regex functions (even though just regexec() is
enough to fix this ASan problem).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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The OFFSETOF_VAR(var, member) macro is implemented in terms of
offsetof(typeof(*var), member) with compilers that know typeof(),
but its fallback implemenation compares &(var->member) and (var) and
count the distance in bytes, i.e.
((uintptr_t)&(var)->member - (uintptr_t)(var))
MSVC's runtime check, when fed an uninitialized 'var', flags this as
a use of an uninitialized variable (and that is legit---uninitialized
contents of 'var' is subtracted) in a debug build.
After auditing all 6 uses of OFFSETOF_VAR(), 1 of them does feed a
potentially uninitialized 'var' to the macro in the beginning of the
for() loop:
#define hashmap_for_each_entry(map, iter, var, member) \
for (var = hashmap_iter_first_entry_offset(map, iter, \
OFFSETOF_VAR(var, member)); \
var; \
var = hashmap_iter_next_entry_offset(iter, \
OFFSETOF_VAR(var, member)))
We can work around this by making sure that var has _some_ value
when OFFSETOF_VAR() is called. Strictly speaking, it invites
undefined behaviour to use NULL here if we end up with pointer
comparison, but MSVC runtime seems to be happy with it, and most
other systems have typeof() and don't even need pointer comparison
fallback code.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Using the CMake support we added some time ago for real with Visual Studio build revealed there were lot of usability improvements possible, which have been carried out. * js/cmake-vs: hashmap_for_each_entry(): workaround MSVC's runtime check failure #3 cmake (Windows): recommend using Visual Studio's built-in CMake support cmake (Windows): initialize vcpkg/build dependencies automatically cmake (Windows): complain when encountering an unknown compiler cmake (Windows): let the `.dll` files be found when running the tests cmake: quote the path accurately when editing `test-lib.sh` cmake: fall back to using `vcpkg`'s `msgfmt.exe` on Windows cmake: ensure that the `vcpkg` packages are found on Windows cmake: do find Git for Windows' shell interpreter cmake: ignore files generated by CMake as run in Visual Studio
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Test 5572.63 ("branch has no merge base with remote-tracking
counterpart") was introduced in 4d36f88 (submodule: do not pass null
OID to setup_revisions, 2018-05-24), as a regression test for the bug
this commit was fixing (preventing a 'fatal: bad object' error when the
current branch and the remote-tracking branch we are pulling have no
merge-base).
However, the commit message for 4d36f88 does not describe in which
real-life situation this bug was encountered. The brief discussion on the
mailing list [1] does not either.
The regression test is not really representative of a real-life
scenario: both the local repository and its upstream have only a single
commit, and the "no merge-base" scenario is simulated by recreating this
root commit in the local repository using 'git commit-tree' before
calling 'git pull --rebase --recurse-submodules'. The rebase succeeds
and results in the local branch being reset to the same root commit as
the upstream branch.
The fix in 4d36f88 modifies 'submodule.c::submodule_touches_in_range'
so that if 'excl_oid' is null, which is the case when the 'git merge-base
--fork-point' invocation in 'builtin/pull.c::get_rebase_fork_point'
errors (no fork-point), then instead of 'incl_oid --not excl_oid' being
passed to setup_revisions, only 'incl_oid' is passed, and
'submodule_touches_in_range' examines 'incl_oid' and all its ancestors
to verify that they do not touch the submodule.
In test 5572.63, the recreated lone root commit in the local repository is
thus the only commit being examined by 'submodule_touches_in_range', and
this commit *adds* the submodule. However, 'submodule_touches_in_range'
*succeeds* because 'combine-diff.c::diff_tree_combined' (see the
backtrace below) returns early since this commit is the root commit
and has no parents.
#0 diff_tree_combined at combine-diff.c:1494
#1 0x0000000100150cbe in diff_tree_combined_merge at combine-diff.c:1649
#2 0x00000001002c7147 in collect_changed_submodules at submodule.c:869
#3 0x00000001002c7d6f in submodule_touches_in_range at submodule.c:1268
#4 0x00000001000ad58b in cmd_pull at builtin/pull.c:1040
In light of all this, add a note in t5572 documenting this peculiar
test.
[1] https://lore.kernel.org/git/20180524204729.19896-1-jonathantanmy@google.com/t/#u
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Feb 26, 2021
The previous change reduced time spent in strlen() while comparing consecutive paths in verify_cache(), but we can do better. The conditional checks the existence of a directory separator at the correct location, but only after doing a string comparison. Swap the order to be logically equivalent but perform fewer string comparisons. To test the effect on performance, I used a repository with over three million paths in the index. I then ran the following command on repeat: git -c index.threads=1 commit --amend --allow-empty --no-edit Here are the measurements over 10 runs after a 5-run warmup: Benchmark #1: v2.30.0 Time (mean ± σ): 854.5 ms ± 18.2 ms Range (min … max): 825.0 ms … 892.8 ms Benchmark #2: Previous change Time (mean ± σ): 833.2 ms ± 10.3 ms Range (min … max): 815.8 ms … 849.7 ms Benchmark #3: This change Time (mean ± σ): 815.5 ms ± 18.1 ms Range (min … max): 795.4 ms … 849.5 ms This change is 2% faster than the previous change and 5% faster than v2.30.0. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Feb 26, 2021
This is modelled on the version of handle_directory_level_conflicts()
from merge-recursive.c, but is massively simplified due to the following
factors:
* strmap API provides simplifications over using direct hashmap
* we have a dirs_removed field in struct rename_info that we have an
easy way to populate from collect_merge_info(); this was already
used in compute_rename_counts() and thus we do not need to check
for condition #2.
* The removal of condition #2 by handling it earlier in the code also
obviates the need to check for condition #3 -- if both sides renamed
a directory, meaning that the directory no longer exists on either
side, then neither side could have added any new files to that
directory, and thus there are no files whose locations we need to
move due to such a directory rename.
In fact, the same logic that makes condition #3 irrelevant means
condition #1 is also irrelevant so we could drop this function.
However, it is cheap to check if both sides rename the same directory,
and doing so can save future computation. So, simply remove any
directories that both sides renamed from the list of directory renames.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Feb 26, 2021
Add some timing instrumentation for both merge-ort and diffcore-rename; I used these to measure and optimize performance in both, and several future patch series will build on these to reduce the timings of some select testcases. === Setup === The primary testcase I used involved rebasing a random topic in the linux kernel (consisting of 35 patches) against an older version. I added two variants, one where I rename a toplevel directory, and another where I only rebase one patch instead of the whole topic. The setup is as follows: $ git clone git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git $ git branch hwmon-updates fd8bdb23b91876ac1e624337bb88dc1dcc21d67e $ git branch hwmon-just-one fd8bdb23b91876ac1e624337bb88dc1dcc21d67e~34 $ git branch base 4703d9119972bf586d2cca76ec6438f819ffa30e $ git switch -c 5.4-renames v5.4 $ git mv drivers pilots # Introduce over 26,000 renames $ git commit -m "Rename drivers/ to pilots/" $ git config merge.renameLimit 30000 $ git config merge.directoryRenames true === Testcases === Now with REBASE standing for either "git rebase [--merge]" (using merge-recursive) or "test-tool fast-rebase" (using merge-ort), the testcases are: Testcase #1: no-renames $ git checkout v5.4^0 $ REBASE --onto HEAD base hwmon-updates Note: technically the name is misleading; there are some renames, but very few. Rename detection only takes about half the overall time. Testcase #2: mega-renames $ git checkout 5.4-renames^0 $ REBASE --onto HEAD base hwmon-updates Testcase #3: just-one-mega $ git checkout 5.4-renames^0 $ REBASE --onto HEAD base hwmon-just-one === Timing results === Overall timings, using hyperfine (1 warmup run, 3 runs for mega-renames, 10 runs for the other two cases): merge-recursive merge-ort no-renames: 18.912 s ± 0.174 s 14.263 s ± 0.053 s mega-renames: 5964.031 s ± 10.459 s 5504.231 s ± 5.150 s just-one-mega: 149.583 s ± 0.751 s 158.534 s ± 0.498 s A single re-run of each with some breakdowns: --- no-renames --- merge-recursive merge-ort overall runtime: 19.302 s 14.257 s inexact rename detection: 7.603 s 7.906 s everything else: 11.699 s 6.351 s --- mega-renames --- merge-recursive merge-ort overall runtime: 5950.195 s 5499.672 s inexact rename detection: 5746.309 s 5487.120 s everything else: 203.886 s 17.552 s --- just-one-mega --- merge-recursive merge-ort overall runtime: 151.001 s 158.582 s inexact rename detection: 143.448 s 157.835 s everything else: 7.553 s 0.747 s === Timing observations === 0) Maximum speedup The "everything else" row represents the maximum speedup we could achieve if we were to somehow infinitely parallelize inexact rename detection, but leave everything else alone. The fact that this is so much smaller than the real runtime (even in the case with virtually no renames) makes it clear just how overwhelmingly large the time spent on rename detection can be. 1) no-renames 1a) merge-ort is faster than merge-recursive, which is nice. However, this still should not be considered good enough. Although the "merge" backend to rebase (merge-recursive) is sometimes faster than the "apply" backend, this is one of those cases where it is not. In fact, even merge-ort is slower. The "apply" backend can complete this testcase in 6.940 s ± 0.485 s which is about 2x faster than merge-ort and 3x faster than merge-recursive. One goal of the merge-ort performance work will be to make it faster than git-am on this (and similar) testcases. 2) mega-renames 2a) Obviously rename detection is a huge cost; it's where most the time is spent. We need to cut that down. If we could somehow infinitely parallelize it and drive its time to 0, the merge-recursive time would drop to about 204s, and the merge-ort time would drop to about 17s. I think this particular stat shows I've subtly baked a couple performance improvements into merge-ort and into fast-rebase already. 3) just-one-mega 3a) not much to say here, it just gives some flavor for how rebasing only one patch compares to rebasing 35. === Goals === This patch is obviously just the beginning. Here are some of my goals that this measurement will help us achieve: * Drive the cost of rename detection down considerably for merges * After the above has been achieved, see if there are other slowness factors (which would have previously been overshadowed by rename detection costs) which we can then focus on and also optimize. * Ensure our rebase testcase that requires little rename detection is noticeably faster with merge-ort than with apply-based rebase. Signed-off-by: Elijah Newren <newren@gmail.com> Acked-by: Taylor Blau <ttaylorr@github.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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write_commit_graph initialises topo_levels using init_topo_level_slab(), next it calls compute_topological_levels() which can cause the slab to grow, we therefore need to clear the slab again using clear_topo_level_slab() when we're done. First introduced in 72a2bfc (commit-graph: add a slab to store topological levels, 2021-01-16). LeakSanitizer output: ==1026==ERROR: LeakSanitizer: detected memory leaks Direct leak of 8 byte(s) in 1 object(s) allocated from: #0 0x498ae9 in realloc /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3 #1 0xafbed8 in xrealloc /src/git/wrapper.c:126:8 #2 0x7966d1 in topo_level_slab_at_peek /src/git/commit-graph.c:71:1 #3 0x7965e0 in topo_level_slab_at /src/git/commit-graph.c:71:1 #4 0x78fbf5 in compute_topological_levels /src/git/commit-graph.c:1472:12 #5 0x78c5c3 in write_commit_graph /src/git/commit-graph.c:2456:2 #6 0x535c5f in graph_write /src/git/builtin/commit-graph.c:299:6 #7 0x5350ca in cmd_commit_graph /src/git/builtin/commit-graph.c:337:11 #8 0x4cddb1 in run_builtin /src/git/git.c:453:11 #9 0x4cabe2 in handle_builtin /src/git/git.c:704:3 #10 0x4cd084 in run_argv /src/git/git.c:771:4 #11 0x4ca424 in cmd_main /src/git/git.c:902:19 #12 0x707fb6 in main /src/git/common-main.c:52:11 #13 0x7fee4249383f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2083f) Indirect leak of 524256 byte(s) in 1 object(s) allocated from: #0 0x498942 in calloc /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3 #1 0xafc088 in xcalloc /src/git/wrapper.c:140:8 #2 0x796870 in topo_level_slab_at_peek /src/git/commit-graph.c:71:1 #3 0x7965e0 in topo_level_slab_at /src/git/commit-graph.c:71:1 #4 0x78fbf5 in compute_topological_levels /src/git/commit-graph.c:1472:12 #5 0x78c5c3 in write_commit_graph /src/git/commit-graph.c:2456:2 #6 0x535c5f in graph_write /src/git/builtin/commit-graph.c:299:6 #7 0x5350ca in cmd_commit_graph /src/git/builtin/commit-graph.c:337:11 #8 0x4cddb1 in run_builtin /src/git/git.c:453:11 #9 0x4cabe2 in handle_builtin /src/git/git.c:704:3 #10 0x4cd084 in run_argv /src/git/git.c:771:4 #11 0x4ca424 in cmd_main /src/git/git.c:902:19 #12 0x707fb6 in main /src/git/common-main.c:52:11 #13 0x7fee4249383f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2083f) SUMMARY: AddressSanitizer: 524264 byte(s) leaked in 2 allocation(s). Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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May 17, 2021
shorten_unambiguous_ref() returns an allocated string. We have to track it separately from the const refname. This leak has existed since: 9ab55da (git symbolic-ref --delete $symref, 2012-10-21) This leak was found when running t0001 with LSAN, see also LSAN output below: Direct leak of 19 byte(s) in 1 object(s) allocated from: #0 0x486514 in strdup /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3 #1 0x9ab048 in xstrdup /home/ahunt/oss-fuzz/git/wrapper.c:29:14 #2 0x8b452f in refs_shorten_unambiguous_ref /home/ahunt/oss-fuzz/git/refs.c #3 0x8b47e8 in shorten_unambiguous_ref /home/ahunt/oss-fuzz/git/refs.c:1287:9 #4 0x679fce in check_symref /home/ahunt/oss-fuzz/git/builtin/symbolic-ref.c:28:14 #5 0x679ad8 in cmd_symbolic_ref /home/ahunt/oss-fuzz/git/builtin/symbolic-ref.c:70:9 #6 0x4cd60d in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11 #7 0x4cb2da in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3 #8 0x4ccc37 in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4 #9 0x4cac29 in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19 #10 0x69cc6e in main /home/ahunt/oss-fuzz/git/common-main.c:52:11 #11 0x7f98388a4349 in __libc_start_main (/lib64/libc.so.6+0x24349) Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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May 17, 2021
dwim_ref() allocs a new string into ref. Instead of setting to NULL to discard it, we can FREE_AND_NULL. This leak appears to have been introduced in: 4cf76f6 (builtin/reset: compute checkout metadata for reset, 2020-03-16) This leak was found when running t0001 with LSAN, see also LSAN output below: Direct leak of 5 byte(s) in 1 object(s) allocated from: #0 0x486514 in strdup /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3 #1 0x9a7108 in xstrdup /home/ahunt/oss-fuzz/git/wrapper.c:29:14 #2 0x8add6b in expand_ref /home/ahunt/oss-fuzz/git/refs.c:670:12 #3 0x8ad777 in repo_dwim_ref /home/ahunt/oss-fuzz/git/refs.c:644:22 #4 0x6394af in dwim_ref /home/ahunt/oss-fuzz/git/./refs.h:162:9 #5 0x637e5c in cmd_reset /home/ahunt/oss-fuzz/git/builtin/reset.c:426:4 #6 0x4cd60d in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11 #7 0x4cb2da in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3 #8 0x4ccc37 in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4 #9 0x4cac29 in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19 #10 0x69c5ce in main /home/ahunt/oss-fuzz/git/common-main.c:52:11 #11 0x7f57ebb9d349 in __libc_start_main (/lib64/libc.so.6+0x24349) Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Most of these pointers can safely be freed when cmd_clone() completes, therefore we make sure to free them. The one exception is that we have to UNLEAK(repo) because it can point either to argv[0], or a malloc'd string returned by absolute_pathdup(). We also have to free(path) in the middle of cmd_clone(): later during cmd_clone(), path is unconditionally overwritten with a different path, triggering a leak. Freeing the first path immediately after use (but only in the case where it contains data) seems like the cleanest solution, as opposed to freeing it unconditionally before path is reused for another path. This leak appears to have been introduced in: f38aa83 (use local cloning if insteadOf makes a local URL, 2014-07-17) These leaks were found when running t0001 with LSAN, see also an excerpt of the LSAN output below (the full list is omitted because it's far too long, and mostly consists of indirect leakage of members of the refs we are freeing). Direct leak of 178 byte(s) in 1 object(s) allocated from: #0 0x49a53d in malloc /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3 #1 0x9a6ff4 in do_xmalloc /home/ahunt/oss-fuzz/git/wrapper.c:41:8 #2 0x9a6fca in xmalloc /home/ahunt/oss-fuzz/git/wrapper.c:62:9 #3 0x8ce296 in copy_ref /home/ahunt/oss-fuzz/git/remote.c:885:8 #4 0x8d2ebd in guess_remote_head /home/ahunt/oss-fuzz/git/remote.c:2215:10 #5 0x51d0c5 in cmd_clone /home/ahunt/oss-fuzz/git/builtin/clone.c:1308:4 #6 0x4cd60d in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11 #7 0x4cb2da in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3 #8 0x4ccc37 in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4 #9 0x4cac29 in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19 #10 0x69c45e in main /home/ahunt/oss-fuzz/git/common-main.c:52:11 #11 0x7f6a459d5349 in __libc_start_main (/lib64/libc.so.6+0x24349) Direct leak of 165 byte(s) in 1 object(s) allocated from: #0 0x49a53d in malloc /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3 #1 0x9a6fc4 in do_xmalloc /home/ahunt/oss-fuzz/git/wrapper.c:41:8 #2 0x9a6f9a in xmalloc /home/ahunt/oss-fuzz/git/wrapper.c:62:9 #3 0x8ce266 in copy_ref /home/ahunt/oss-fuzz/git/remote.c:885:8 #4 0x51e9bd in wanted_peer_refs /home/ahunt/oss-fuzz/git/builtin/clone.c:574:21 #5 0x51cfe1 in cmd_clone /home/ahunt/oss-fuzz/git/builtin/clone.c:1284:17 #6 0x4cd60d in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11 #7 0x4cb2da in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3 #8 0x4ccc37 in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4 #9 0x4cac29 in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19 #10 0x69c42e in main /home/ahunt/oss-fuzz/git/common-main.c:52:11 #11 0x7f8fef0c2349 in __libc_start_main (/lib64/libc.so.6+0x24349) Direct leak of 178 byte(s) in 1 object(s) allocated from: #0 0x49a53d in malloc /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3 #1 0x9a6ff4 in do_xmalloc /home/ahunt/oss-fuzz/git/wrapper.c:41:8 #2 0x9a6fca in xmalloc /home/ahunt/oss-fuzz/git/wrapper.c:62:9 #3 0x8ce296 in copy_ref /home/ahunt/oss-fuzz/git/remote.c:885:8 #4 0x8d2ebd in guess_remote_head /home/ahunt/oss-fuzz/git/remote.c:2215:10 #5 0x51d0c5 in cmd_clone /home/ahunt/oss-fuzz/git/builtin/clone.c:1308:4 #6 0x4cd60d in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11 #7 0x4cb2da in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3 #8 0x4ccc37 in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4 #9 0x4cac29 in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19 #10 0x69c45e in main /home/ahunt/oss-fuzz/git/common-main.c:52:11 #11 0x7f6a459d5349 in __libc_start_main (/lib64/libc.so.6+0x24349) Direct leak of 165 byte(s) in 1 object(s) allocated from: #0 0x49a6b2 in calloc /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3 #1 0x9a72f2 in xcalloc /home/ahunt/oss-fuzz/git/wrapper.c:140:8 #2 0x8ce203 in alloc_ref_with_prefix /home/ahunt/oss-fuzz/git/remote.c:867:20 #3 0x8ce1a2 in alloc_ref /home/ahunt/oss-fuzz/git/remote.c:875:9 #4 0x72f63e in process_ref_v2 /home/ahunt/oss-fuzz/git/connect.c:426:8 #5 0x72f21a in get_remote_refs /home/ahunt/oss-fuzz/git/connect.c:525:8 #6 0x979ab7 in handshake /home/ahunt/oss-fuzz/git/transport.c:305:4 #7 0x97872d in get_refs_via_connect /home/ahunt/oss-fuzz/git/transport.c:339:9 #8 0x9774b5 in transport_get_remote_refs /home/ahunt/oss-fuzz/git/transport.c:1388:4 #9 0x51cf80 in cmd_clone /home/ahunt/oss-fuzz/git/builtin/clone.c:1271:9 #10 0x4cd60d in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11 #11 0x4cb2da in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3 #12 0x4ccc37 in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4 #13 0x4cac29 in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19 #14 0x69c45e in main /home/ahunt/oss-fuzz/git/common-main.c:52:11 #15 0x7f6a459d5349 in __libc_start_main (/lib64/libc.so.6+0x24349) Direct leak of 105 byte(s) in 1 object(s) allocated from: #0 0x49a859 in realloc /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3 #1 0x9a71f6 in xrealloc /home/ahunt/oss-fuzz/git/wrapper.c:126:8 #2 0x93622d in strbuf_grow /home/ahunt/oss-fuzz/git/strbuf.c:98:2 #3 0x937a73 in strbuf_addch /home/ahunt/oss-fuzz/git/./strbuf.h:231:3 #4 0x939fcd in strbuf_add_absolute_path /home/ahunt/oss-fuzz/git/strbuf.c:911:4 #5 0x69d3ce in absolute_pathdup /home/ahunt/oss-fuzz/git/abspath.c:261:2 #6 0x51c688 in cmd_clone /home/ahunt/oss-fuzz/git/builtin/clone.c:1021:10 #7 0x4cd60d in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11 #8 0x4cb2da in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3 #9 0x4ccc37 in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4 #10 0x4cac29 in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19 #11 0x69c45e in main /home/ahunt/oss-fuzz/git/common-main.c:52:11 #12 0x7f6a459d5349 in __libc_start_main (/lib64/libc.so.6+0x24349) Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Make sure that we release the temporary strbuf during dwim_branch() for all codepaths (and not just for the early return). This leak appears to have been introduced in: f60a7b7 (worktree: teach "add" to check out existing branches, 2018-04-24) Note that UNLEAK(branchname) is still needed: the returned result is used in add(), and is stored in a pointer which is used to point at one of: - a string literal ("HEAD") - member of argv (whatever the user specified in their invocation) - or our newly allocated string returned from dwim_branch() Fixing the branchname leak isn't impossible, but does not seem worthwhile given that add() is called directly from cmd_main(), and cmd_main() returns immediately thereafter - UNLEAK is good enough. This leak was found when running t0001 with LSAN, see also LSAN output below: Direct leak of 60 byte(s) in 1 object(s) allocated from: #0 0x49a859 in realloc /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3 #1 0x9ab076 in xrealloc /home/ahunt/oss-fuzz/git/wrapper.c:126:8 #2 0x939fcd in strbuf_grow /home/ahunt/oss-fuzz/git/strbuf.c:98:2 #3 0x93af53 in strbuf_splice /home/ahunt/oss-fuzz/git/strbuf.c:239:3 #4 0x83559a in strbuf_check_branch_ref /home/ahunt/oss-fuzz/git/object-name.c:1593:2 #5 0x6988b9 in dwim_branch /home/ahunt/oss-fuzz/git/builtin/worktree.c:454:20 #6 0x695f8f in add /home/ahunt/oss-fuzz/git/builtin/worktree.c:525:19 #7 0x694a04 in cmd_worktree /home/ahunt/oss-fuzz/git/builtin/worktree.c:1036:10 #8 0x4cd60d in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11 #9 0x4cb2da in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3 #10 0x4ccc37 in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4 #11 0x4cac29 in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19 #12 0x69caee in main /home/ahunt/oss-fuzz/git/common-main.c:52:11 #13 0x7f7b7dd10349 in __libc_start_main (/lib64/libc.so.6+0x24349) Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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The primary goal of this change is to stop leaking init_db_template_dir.
This leak can happen because:
1. git_init_db_config() allocates new memory into init_db_template_dir
without first freeing the existing value.
2. init_db_template_dir might already contain data, either because:
2.1 git_config() can be invoked twice with this callback in a single
process - at least 2 allocations are likely.
2.2 A single git_config() allocation can invoke the callback multiple
times for a given key (see further explanation in the function
docs) - each of those calls will trigger another leak.
The simplest fix for the leak would be to free(init_db_template_dir)
before overwriting it. Instead we choose to convert to fetching
init.templatedir via git_config_get_value() as that is more explicit,
more efficient, and avoids allocations (the returned result is owned by
the config cache, so we aren't responsible for freeing it).
If we remove init_db_template_dir, git_init_db_config() ends up being
responsible only for forwarding core.* config values to
platform_core_config(). However platform_core_config() already ignores
non-core.* config values, so we can safely remove git_init_db_config()
and invoke git_config() directly with platform_core_config() as the
callback.
The platform_core_config forwarding was originally added in:
2878533 (mingw: respect core.hidedotfiles = false in git-init again, 2019-03-11
And I suspect the potential for a leak existed since the original
implementation of git_init_db_config in:
90b4518 (Add `init.templatedir` configuration variable., 2010-02-17)
LSAN output from t0001:
Direct leak of 73 byte(s) in 1 object(s) allocated from:
#0 0x49a859 in realloc /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0x9a7276 in xrealloc /home/ahunt/oss-fuzz/git/wrapper.c:126:8
#2 0x9362ad in strbuf_grow /home/ahunt/oss-fuzz/git/strbuf.c:98:2
#3 0x936eaa in strbuf_add /home/ahunt/oss-fuzz/git/strbuf.c:295:2
#4 0x868112 in strbuf_addstr /home/ahunt/oss-fuzz/git/./strbuf.h:304:2
#5 0x86a8ad in expand_user_path /home/ahunt/oss-fuzz/git/path.c:758:2
#6 0x720bb1 in git_config_pathname /home/ahunt/oss-fuzz/git/config.c:1287:10
#7 0x5960e2 in git_init_db_config /home/ahunt/oss-fuzz/git/builtin/init-db.c:161:11
#8 0x7255b8 in configset_iter /home/ahunt/oss-fuzz/git/config.c:1982:7
#9 0x7253fc in repo_config /home/ahunt/oss-fuzz/git/config.c:2311:2
#10 0x725ca7 in git_config /home/ahunt/oss-fuzz/git/config.c:2399:2
#11 0x593e8d in create_default_files /home/ahunt/oss-fuzz/git/builtin/init-db.c:225:2
#12 0x5935c6 in init_db /home/ahunt/oss-fuzz/git/builtin/init-db.c:449:11
#13 0x59588e in cmd_init_db /home/ahunt/oss-fuzz/git/builtin/init-db.c:714:9
#14 0x4cd60d in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11
#15 0x4cb2da in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3
#16 0x4ccc37 in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4
#17 0x4cac29 in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19
#18 0x69c4de in main /home/ahunt/oss-fuzz/git/common-main.c:52:11
#19 0x7f23552d6349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Signed-off-by: Andrzej Hunt <ajrhunt@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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…sponse query_result can be be an empty strbuf (STRBUF_INIT) - in that case trying to read 3 bytes triggers a buffer overflow read (as query_result.buf = '\0'). Therefore we need to check query_result's length before trying to read 3 bytes. This overflow was introduced in: 940b94f (fsmonitor: log invocation of FSMonitor hook to trace2, 2021-02-03) It was found when running the test-suite against ASAN, and can be most easily reproduced with the following command: make GIT_TEST_OPTS="-v" DEFAULT_TEST_TARGET="t7519-status-fsmonitor.sh" \ SANITIZE=address DEVELOPER=1 test ==2235==ERROR: AddressSanitizer: global-buffer-overflow on address 0x0000019e6e5e at pc 0x00000043745c bp 0x7fffd382c520 sp 0x7fffd382bcc8 READ of size 3 at 0x0000019e6e5e thread T0 #0 0x43745b in MemcmpInterceptorCommon(void*, int (*)(void const*, void const*, unsigned long), void const*, void const*, unsigned long) /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/../sanitizer_common/sanitizer_common_interceptors.inc:842:7 #1 0x43786d in bcmp /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/../sanitizer_common/sanitizer_common_interceptors.inc:887:10 #2 0x80b146 in fsmonitor_is_trivial_response /home/ahunt/oss-fuzz/git/fsmonitor.c:192:10 #3 0x80b146 in query_fsmonitor /home/ahunt/oss-fuzz/git/fsmonitor.c:175:7 #4 0x80a749 in refresh_fsmonitor /home/ahunt/oss-fuzz/git/fsmonitor.c:267:21 #5 0x80bad1 in tweak_fsmonitor /home/ahunt/oss-fuzz/git/fsmonitor.c:429:4 #6 0x90f040 in read_index_from /home/ahunt/oss-fuzz/git/read-cache.c:2321:3 #7 0x8e5d08 in repo_read_index_preload /home/ahunt/oss-fuzz/git/preload-index.c:164:15 #8 0x52dd45 in prepare_index /home/ahunt/oss-fuzz/git/builtin/commit.c:363:6 #9 0x52a188 in cmd_commit /home/ahunt/oss-fuzz/git/builtin/commit.c:1588:15 #10 0x4ce77e in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11 #11 0x4ccb18 in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3 #12 0x4cb01c in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4 #13 0x4cb01c in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19 #14 0x6aca8d in main /home/ahunt/oss-fuzz/git/common-main.c:52:11 #15 0x7fb027bf5349 in __libc_start_main (/lib64/libc.so.6+0x24349) #16 0x4206b9 in _start /home/abuild/rpmbuild/BUILD/glibc-2.26/csu/../sysdeps/x86_64/start.S:120 0x0000019e6e5e is located 2 bytes to the left of global variable 'strbuf_slopbuf' defined in 'strbuf.c:51:6' (0x19e6e60) of size 1 'strbuf_slopbuf' is ascii string '' 0x0000019e6e5e is located 126 bytes to the right of global variable 'signals' defined in 'sigchain.c:11:31' (0x19e6be0) of size 512 SUMMARY: AddressSanitizer: global-buffer-overflow /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/../sanitizer_common/sanitizer_common_interceptors.inc:842:7 in MemcmpInterceptorCommon(void*, int (*)(void const*, void const*, unsigned long), void const*, void const*, unsigned long) Shadow bytes around the buggy address: 0x000080334d70: f9 f9 f9 f9 00 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 0x000080334d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x000080334d90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x000080334da0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x000080334db0: 00 00 00 00 00 00 00 00 00 00 00 00 f9 f9 f9 f9 =>0x000080334dc0: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9[f9]01 f9 f9 f9 0x000080334dd0: f9 f9 f9 f9 03 f9 f9 f9 f9 f9 f9 f9 02 f9 f9 f9 0x000080334de0: f9 f9 f9 f9 00 f9 f9 f9 f9 f9 f9 f9 04 f9 f9 f9 0x000080334df0: f9 f9 f9 f9 01 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 0x000080334e00: f9 f9 f9 f9 00 00 00 00 f9 f9 f9 f9 01 f9 f9 f9 0x000080334e10: f9 f9 f9 f9 04 f9 f9 f9 f9 f9 f9 f9 00 f9 f9 f9 Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc Array cookie: ac Intra object redzone: bb ASan internal: fe Left alloca redzone: ca Right alloca redzone: cb Shadow gap: cc Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Acked-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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preprocess_options() allocates new strings for help messages for OPTION_ALIAS. Therefore we also need to clean those help messages up when freeing the returned options. First introduced in: 7c28058 (parse-options: teach "git cmd -h" to show alias as alias, 2020-03-16) The preprocessed options themselves no longer contain any indication that a given option is/was an alias - therefore we add a new flag to indicate former aliases. (An alternative approach would be to look back at the original options to determine which options are aliases - but that seems like a fragile approach. Or we could even look at the alias_groups list - which might be less fragile, but would be slower as it requires nested looping.) As far as I can tell, parse_options() is only ever used once per command, and the help messages are small - hence this leak has very little impact. This leak was found while running t0001. LSAN output can be found below: Direct leak of 65 byte(s) in 1 object(s) allocated from: #0 0x49a859 in realloc /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3 #1 0x9aae36 in xrealloc /home/ahunt/oss-fuzz/git/wrapper.c:126:8 #2 0x939d8d in strbuf_grow /home/ahunt/oss-fuzz/git/strbuf.c:98:2 #3 0x93b936 in strbuf_vaddf /home/ahunt/oss-fuzz/git/strbuf.c:392:3 #4 0x93b7ff in strbuf_addf /home/ahunt/oss-fuzz/git/strbuf.c:333:2 #5 0x86747e in preprocess_options /home/ahunt/oss-fuzz/git/parse-options.c:666:3 #6 0x866ed2 in parse_options /home/ahunt/oss-fuzz/git/parse-options.c:847:17 #7 0x51c4a7 in cmd_clone /home/ahunt/oss-fuzz/git/builtin/clone.c:989:9 #8 0x4cd60d in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11 #9 0x4cb2da in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3 #10 0x4ccc37 in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4 #11 0x4cac29 in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19 #12 0x69c9fe in main /home/ahunt/oss-fuzz/git/common-main.c:52:11 #13 0x7fdac42d4349 in __libc_start_main (/lib64/libc.so.6+0x24349) Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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transport_get_remote_refs() can populate the transport struct's
remote_refs. transport_disconnect() is already responsible for most of
transport's cleanup - therefore we also take care of freeing remote_refs
there.
There are 2 locations where transport_disconnect() is called before
we're done using the returned remote_refs. This patch changes those
callsites to only call transport_disconnect() after the returned refs
are no longer being used - which is necessary to safely be able to
free remote_refs during transport_disconnect().
This commit fixes the following leak which was found while running
t0000, but is expected to also fix the same pattern of leak in all
locations that use transport_get_remote_refs():
Direct leak of 165 byte(s) in 1 object(s) allocated from:
#0 0x49a6b2 in calloc /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
#1 0x9a72f2 in xcalloc /home/ahunt/oss-fuzz/git/wrapper.c:140:8
#2 0x8ce203 in alloc_ref_with_prefix /home/ahunt/oss-fuzz/git/remote.c:867:20
#3 0x8ce1a2 in alloc_ref /home/ahunt/oss-fuzz/git/remote.c:875:9
#4 0x72f63e in process_ref_v2 /home/ahunt/oss-fuzz/git/connect.c:426:8
#5 0x72f21a in get_remote_refs /home/ahunt/oss-fuzz/git/connect.c:525:8
#6 0x979ab7 in handshake /home/ahunt/oss-fuzz/git/transport.c:305:4
#7 0x97872d in get_refs_via_connect /home/ahunt/oss-fuzz/git/transport.c:339:9
#8 0x9774b5 in transport_get_remote_refs /home/ahunt/oss-fuzz/git/transport.c:1388:4
#9 0x51cf80 in cmd_clone /home/ahunt/oss-fuzz/git/builtin/clone.c:1271:9
#10 0x4cd60d in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11
#11 0x4cb2da in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3
#12 0x4ccc37 in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4
#13 0x4cac29 in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19
#14 0x69c45e in main /home/ahunt/oss-fuzz/git/common-main.c:52:11
#15 0x7f6a459d5349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Signed-off-by: Andrzej Hunt <ajrhunt@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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versions could be an empty string_list. In that case, versions->items is NULL, and we shouldn't be trying to perform pointer arithmetic with it (as that results in undefined behaviour). Moreover we only use the results of this calculation once when calling QSORT. Therefore we choose to skip creating relevant_entries and call QSORT directly with our manipulated pointers (but only if there's data requiring sorting). This lets us avoid abusing the string_list API, and saves us from having to explain why this abuse is OK. Finally, an assertion is added to make sure that write_tree() is called with a valid offset. This issue has probably existed since: ee4012d (merge-ort: step 2 of tree writing -- function to create tree object, 2020-12-13) But it only started occurring during tests since tests started using merge-ort: f3b964a (Add testing with merge-ort merge strategy, 2021-03-20) For reference - here's the original UBSAN commit that implemented this check, it sounds like this behaviour isn't actually likely to cause any issues (but we might as well fix it regardless): https://reviews.llvm.org/D67122 UBSAN output from t3404 or t5601: merge-ort.c:2669:43: runtime error: applying zero offset to null pointer #0 0x78bb53 in write_tree merge-ort.c:2669:43 #1 0x7856c9 in process_entries merge-ort.c:3303:2 #2 0x782317 in merge_ort_nonrecursive_internal merge-ort.c:3744:2 #3 0x77feef in merge_incore_nonrecursive merge-ort.c:3853:2 #4 0x6f6a5c in do_recursive_merge sequencer.c:640:3 #5 0x6f6a5c in do_pick_commit sequencer.c:2221:9 #6 0x6ef055 in single_pick sequencer.c:4814:9 #7 0x6ef055 in sequencer_pick_revisions sequencer.c:4867:10 #8 0x4fb392 in run_sequencer revert.c:225:9 #9 0x4fa5b0 in cmd_revert revert.c:235:8 #10 0x42abd7 in run_builtin git.c:453:11 #11 0x429531 in handle_builtin git.c:704:3 #12 0x4282fb in run_argv git.c:771:4 #13 0x4282fb in cmd_main git.c:902:19 #14 0x524b63 in main common-main.c:52:11 #15 0x7fc2ca340349 in __libc_start_main (/lib64/libc.so.6+0x24349) #16 0x4072b9 in _start start.S:120 SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior merge-ort.c:2669:43 in Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Reviewed-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Commit 878f988 (t/test-lib: teach --chain-lint to detect broken &&-chains in subshells, 2018-07-11) introduced additional chain-lint tests which add an extra "sed" pipeline to each test we run. This has a measurable impact on runtime. Here are timings with and without a new environment variable (added by this patch) that lets you disable just the additional sed-based chain-lint tests: Benchmark #1: GIT_TEST_CHAIN_LINT_HARDER=1 make test Time (mean ± σ): 64.202 s ± 1.030 s [User: 622.469 s, System: 301.402 s] Range (min … max): 61.571 s … 65.662 s 10 runs Benchmark #2: GIT_TEST_CHAIN_LINT_HARDER=0 make test Time (mean ± σ): 57.591 s ± 0.333 s [User: 529.368 s, System: 270.618 s] Range (min … max): 57.143 s … 58.309 s 10 runs Summary 'GIT_TEST_CHAIN_LINT_HARDER=0 make test' ran 1.11 ± 0.02 times faster than 'GIT_TEST_CHAIN_LINT_HARDER=1 make test' Of course those extra lint checks are doing something useful, so paying a few extra seconds (at least on Linux) isn't so bad (though note the CPU time; we're bounded in our parallel run here by the slowest test, so it really is ~120s of CPU improvement). But we can observe that there are some test scripts where they produce a much stronger effect, and provide less value. In t0027 and t3070 we run a very large number of small tests, all driven by a series of functions/loops which are filling in the test bodies. There we get much less bang for our buck in terms of bug-finding versus CPU cost. This patch introduces a mechanism for controlling when those extra lint checks are run, at two levels: - a user can ask to disable or to force-enable the checks by setting GIT_TEST_CHAIN_LINT_HARDER - if the user hasn't specified a preference, individual scripts can disable the checks by setting GIT_TEST_CHAIN_LINT_HARDER_DEFAULT; scripts which don't set that get the current behavior of enabling them. In addition, this patch flips the default for t0027 and t3070's mass-generated sections to disable the extra checks. Here are the timing results for t0027: Benchmark #1: GIT_TEST_CHAIN_LINT_HARDER=1 ./t0027-auto-crlf.sh Time (mean ± σ): 17.078 s ± 0.848 s [User: 14.878 s, System: 7.075 s] Range (min … max): 15.952 s … 18.421 s 10 runs Benchmark #2: GIT_TEST_CHAIN_LINT_HARDER=0 ./t0027-auto-crlf.sh Time (mean ± σ): 9.063 s ± 0.759 s [User: 7.890 s, System: 3.362 s] Range (min … max): 7.747 s … 10.619 s 10 runs Benchmark #3: ./t0027-auto-crlf.sh Time (mean ± σ): 9.186 s ± 0.881 s [User: 7.957 s, System: 3.427 s] Range (min … max): 7.796 s … 10.498 s 10 runs Summary 'GIT_TEST_CHAIN_LINT_HARDER=0 ./t0027-auto-crlf.sh' ran 1.01 ± 0.13 times faster than './t0027-auto-crlf.sh' 1.88 ± 0.18 times faster than 'GIT_TEST_CHAIN_LINT_HARDER=1 ./t0027-auto-crlf.sh' We can see that disabling the checks for the whole script buys us an almost 2x speedup. But the new default behavior, disabling them only for the mass-generated part, gets us most of that speedup (but still leaves the checks on for further manual tests people might write). As a side note, I'd caution about comparing runtimes and CPU seconds between this timing and the earlier "make test" one. In "make test", we're running a lot of scripts in parallel, so the CPU is throttling down (and thus a CPU second saved here would count for more during a parallel run; the same work takes more CPU seconds there). We get similar results for t3070: Benchmark #1: GIT_TEST_CHAIN_LINT_HARDER=1 ./t3070-wildmatch.sh Time (mean ± σ): 20.054 s ± 3.967 s [User: 16.003 s, System: 8.286 s] Range (min … max): 11.891 s … 23.671 s 10 runs Benchmark #2: GIT_TEST_CHAIN_LINT_HARDER=0 ./t3070-wildmatch.sh Time (mean ± σ): 12.399 s ± 2.256 s [User: 7.542 s, System: 5.342 s] Range (min … max): 9.606 s … 15.727 s 10 runs Benchmark #3: ./t3070-wildmatch.sh Time (mean ± σ): 10.726 s ± 3.476 s [User: 6.790 s, System: 4.365 s] Range (min … max): 5.444 s … 15.376 s 10 runs Summary './t3070-wildmatch.sh' ran 1.16 ± 0.43 times faster than 'GIT_TEST_CHAIN_LINT_HARDER=0 ./t3070-wildmatch.sh' 1.87 ± 0.71 times faster than 'GIT_TEST_CHAIN_LINT_HARDER=1 ./t3070-wildmatch.sh' Again, we get almost a 2x speedup disabling these. In this case, there are no tests not covered by the script's "default to disable" behavior, so the second two benchmarks should be the same (and while they do differ, you can see the variance is quite high but they're within one standard deviation). So it seems like for these two scripts, at least, disabling the extra checks is a reasonable tradeoff. Sadly, the overall runtime of "make test" on my system doesn't get much faster. But that's because we're mostly limited by the cost of the single biggest test. Here are the top-5 tests by wall-clock time from a parallel run, before my patch: 57.9192368984222 t9001-send-email.sh 45.6329638957977 t0027-auto-crlf.sh 32.5278220176697 t3070-wildmatch.sh 22.2701289653778 t7610-mergetool.sh 20.8635759353638 t1701-racy-split-index.sh And after: 57.1476998329163 t9001-send-email.sh 33.776211977005 t0027-auto-crlf.sh 21.3116669654846 t7610-mergetool.sh 20.7748689651489 t1701-racy-split-index.sh 19.6957249641418 t7112-reset-submodule.sh We dropped 12s from t0027, and t3070 dropped off our list entirely at around 16s. In both cases we're bound by t9001, but its slowness is due to the actual tests, so we'll have to deal with it in a different way. But this reduces overall CPU, and means that dealing with t9001 (by improving the speed of send-email or splitting it apart) will let us reduce our overall runtime even on multi-core machines. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
jiangxin
pushed a commit
that referenced
this pull request
Aug 3, 2021
ibuf can be reused for multiple iterations of the loop. Specifically:
deflate() overwrites s.avail_in to show how much of the input buffer
has not been processed yet - and sometimes leaves 'avail_in > 0', in
which case ibuf will be processed again during the loop's subsequent
iteration.
But if we declare ibuf within the loop, then (in theory) we get a new
(and uninitialised) buffer for every iteration. In practice, my compiler
seems to resue the same buffer - meaning that this code does work - but
it doesn't seem safe to rely on this behaviour. MSAN correctly catches
this issue - as soon as we hit the 's.avail_in > 0' condition, we end up
reading from what seems to be uninitialised memory.
Therefore, we move ibuf out of the loop, making this reuse safe.
See MSAN output from t1050-large below - the interesting part is the
ibuf creation at the end, although there's a lot of indirection before
we reach the read from unitialised memory:
==11294==WARNING: MemorySanitizer: use-of-uninitialized-value
#0 0x7f75db58fb1c in crc32_little crc32.c:283:9
#1 0x7f75db58d5b3 in crc32_z crc32.c:220:20
#2 0x7f75db59668c in crc32 crc32.c:242:12
#3 0x8c94f8 in hashwrite csum-file.c:101:15
#4 0x825faf in stream_to_pack bulk-checkin.c:154:5
#5 0x82467b in deflate_to_pack bulk-checkin.c:225:8
#6 0x823ff1 in index_bulk_checkin bulk-checkin.c:264:15
#7 0xa7cff2 in index_stream object-file.c:2234:9
#8 0xa7bff7 in index_fd object-file.c:2256:9
#9 0xa7d22d in index_path object-file.c:2274:7
#10 0xb3c8c9 in add_to_index read-cache.c:802:7
#11 0xb3e039 in add_file_to_index read-cache.c:835:9
#12 0x4a99c3 in add_files add.c:458:7
#13 0x4a7276 in cmd_add add.c:670:18
#14 0x4a1e76 in run_builtin git.c:461:11
#15 0x49e1e7 in handle_builtin git.c:714:3
#16 0x4a0c08 in run_argv git.c:781:4
#17 0x49d5a8 in cmd_main git.c:912:19
#18 0x7974da in main common-main.c:52:11
#19 0x7f75da66f349 in __libc_start_main (/lib64/libc.so.6+0x24349)
#20 0x421bd9 in _start start.S:120
Uninitialized value was stored to memory at
#0 0x7f75db58fa6b in crc32_little crc32.c:283:9
#1 0x7f75db58d5b3 in crc32_z crc32.c:220:20
#2 0x7f75db59668c in crc32 crc32.c:242:12
#3 0x8c94f8 in hashwrite csum-file.c:101:15
#4 0x825faf in stream_to_pack bulk-checkin.c:154:5
#5 0x82467b in deflate_to_pack bulk-checkin.c:225:8
#6 0x823ff1 in index_bulk_checkin bulk-checkin.c:264:15
#7 0xa7cff2 in index_stream object-file.c:2234:9
#8 0xa7bff7 in index_fd object-file.c:2256:9
#9 0xa7d22d in index_path object-file.c:2274:7
#10 0xb3c8c9 in add_to_index read-cache.c:802:7
#11 0xb3e039 in add_file_to_index read-cache.c:835:9
#12 0x4a99c3 in add_files add.c:458:7
#13 0x4a7276 in cmd_add add.c:670:18
#14 0x4a1e76 in run_builtin git.c:461:11
#15 0x49e1e7 in handle_builtin git.c:714:3
#16 0x4a0c08 in run_argv git.c:781:4
#17 0x49d5a8 in cmd_main git.c:912:19
#18 0x7974da in main common-main.c:52:11
#19 0x7f75da66f349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Uninitialized value was stored to memory at
#0 0x447eb9 in __msan_memcpy msan_interceptors.cpp:1558:3
#1 0x7f75db5c2011 in flush_pending deflate.c:746:5
#2 0x7f75db5cafa0 in deflate_stored deflate.c:1815:9
#3 0x7f75db5bb7d2 in deflate deflate.c:1005:34
#4 0xd80b7f in git_deflate zlib.c:244:12
#5 0x825dff in stream_to_pack bulk-checkin.c:140:12
#6 0x82467b in deflate_to_pack bulk-checkin.c:225:8
#7 0x823ff1 in index_bulk_checkin bulk-checkin.c:264:15
#8 0xa7cff2 in index_stream object-file.c:2234:9
#9 0xa7bff7 in index_fd object-file.c:2256:9
#10 0xa7d22d in index_path object-file.c:2274:7
#11 0xb3c8c9 in add_to_index read-cache.c:802:7
#12 0xb3e039 in add_file_to_index read-cache.c:835:9
#13 0x4a99c3 in add_files add.c:458:7
#14 0x4a7276 in cmd_add add.c:670:18
#15 0x4a1e76 in run_builtin git.c:461:11
#16 0x49e1e7 in handle_builtin git.c:714:3
#17 0x4a0c08 in run_argv git.c:781:4
#18 0x49d5a8 in cmd_main git.c:912:19
#19 0x7974da in main common-main.c:52:11
Uninitialized value was stored to memory at
#0 0x447eb9 in __msan_memcpy msan_interceptors.cpp:1558:3
#1 0x7f75db644241 in _tr_stored_block trees.c:873:5
#2 0x7f75db5cad7c in deflate_stored deflate.c:1813:9
#3 0x7f75db5bb7d2 in deflate deflate.c:1005:34
#4 0xd80b7f in git_deflate zlib.c:244:12
#5 0x825dff in stream_to_pack bulk-checkin.c:140:12
#6 0x82467b in deflate_to_pack bulk-checkin.c:225:8
#7 0x823ff1 in index_bulk_checkin bulk-checkin.c:264:15
#8 0xa7cff2 in index_stream object-file.c:2234:9
#9 0xa7bff7 in index_fd object-file.c:2256:9
#10 0xa7d22d in index_path object-file.c:2274:7
#11 0xb3c8c9 in add_to_index read-cache.c:802:7
#12 0xb3e039 in add_file_to_index read-cache.c:835:9
#13 0x4a99c3 in add_files add.c:458:7
#14 0x4a7276 in cmd_add add.c:670:18
#15 0x4a1e76 in run_builtin git.c:461:11
#16 0x49e1e7 in handle_builtin git.c:714:3
#17 0x4a0c08 in run_argv git.c:781:4
#18 0x49d5a8 in cmd_main git.c:912:19
#19 0x7974da in main common-main.c:52:11
Uninitialized value was stored to memory at
#0 0x447eb9 in __msan_memcpy msan_interceptors.cpp:1558:3
#1 0x7f75db5c8fcf in deflate_stored deflate.c:1783:9
#2 0x7f75db5bb7d2 in deflate deflate.c:1005:34
#3 0xd80b7f in git_deflate zlib.c:244:12
#4 0x825dff in stream_to_pack bulk-checkin.c:140:12
#5 0x82467b in deflate_to_pack bulk-checkin.c:225:8
#6 0x823ff1 in index_bulk_checkin bulk-checkin.c:264:15
#7 0xa7cff2 in index_stream object-file.c:2234:9
#8 0xa7bff7 in index_fd object-file.c:2256:9
#9 0xa7d22d in index_path object-file.c:2274:7
#10 0xb3c8c9 in add_to_index read-cache.c:802:7
#11 0xb3e039 in add_file_to_index read-cache.c:835:9
#12 0x4a99c3 in add_files add.c:458:7
#13 0x4a7276 in cmd_add add.c:670:18
#14 0x4a1e76 in run_builtin git.c:461:11
#15 0x49e1e7 in handle_builtin git.c:714:3
#16 0x4a0c08 in run_argv git.c:781:4
#17 0x49d5a8 in cmd_main git.c:912:19
#18 0x7974da in main common-main.c:52:11
#19 0x7f75da66f349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Uninitialized value was stored to memory at
#0 0x447eb9 in __msan_memcpy msan_interceptors.cpp:1558:3
#1 0x7f75db5ea545 in read_buf deflate.c:1181:5
#2 0x7f75db5c97f7 in deflate_stored deflate.c:1791:9
#3 0x7f75db5bb7d2 in deflate deflate.c:1005:34
#4 0xd80b7f in git_deflate zlib.c:244:12
#5 0x825dff in stream_to_pack bulk-checkin.c:140:12
#6 0x82467b in deflate_to_pack bulk-checkin.c:225:8
#7 0x823ff1 in index_bulk_checkin bulk-checkin.c:264:15
#8 0xa7cff2 in index_stream object-file.c:2234:9
#9 0xa7bff7 in index_fd object-file.c:2256:9
#10 0xa7d22d in index_path object-file.c:2274:7
#11 0xb3c8c9 in add_to_index read-cache.c:802:7
#12 0xb3e039 in add_file_to_index read-cache.c:835:9
#13 0x4a99c3 in add_files add.c:458:7
#14 0x4a7276 in cmd_add add.c:670:18
#15 0x4a1e76 in run_builtin git.c:461:11
#16 0x49e1e7 in handle_builtin git.c:714:3
#17 0x4a0c08 in run_argv git.c:781:4
#18 0x49d5a8 in cmd_main git.c:912:19
#19 0x7974da in main common-main.c:52:11
Uninitialized value was created by an allocation of 'ibuf' in the stack frame of function 'stream_to_pack'
#0 0x825710 in stream_to_pack bulk-checkin.c:101
SUMMARY: MemorySanitizer: use-of-uninitialized-value crc32.c:283:9 in crc32_little
Exiting
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
jiangxin
pushed a commit
that referenced
this pull request
Aug 3, 2021
cache_entry contains an object_id, and compare_ce_content() would
include that field when calling memcmp on a subset of the cache_entry.
Depending on which hashing algorithm is being used, only part of
object_id.hash is actually being used, therefore including it in a
memcmp() is incorrect. Instead we choose to exclude the object_id when
calling memcmp(), and call oideq() separately.
This issue was found when running t1700-split-index with MSAN, see MSAN
output below (on my machine, offset 76 corresponds to 4 bytes after the
start of object_id.hash).
Uninitialized bytes in MemcmpInterceptorCommon at offset 76 inside [0x7f60e7c00118, 92)
==27914==WARNING: MemorySanitizer: use-of-uninitialized-value
#0 0x4524ee in memcmp /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/msan/../sanitizer_common/sanitizer_common_interceptors.inc:873:10
#1 0xc867ae in compare_ce_content /home/ahunt/git/git/split-index.c:208:8
#2 0xc859fb in prepare_to_write_split_index /home/ahunt/git/git/split-index.c:336:9
#3 0xb4bbca in write_split_index /home/ahunt/git/git/read-cache.c:3107:2
#4 0xb42b4d in write_locked_index /home/ahunt/git/git/read-cache.c:3295:8
#5 0x638058 in try_merge_strategy /home/ahunt/git/git/builtin/merge.c:758:7
#6 0x63057f in cmd_merge /home/ahunt/git/git/builtin/merge.c:1663:9
#7 0x4a1e76 in run_builtin /home/ahunt/git/git/git.c:461:11
#8 0x49e1e7 in handle_builtin /home/ahunt/git/git/git.c:714:3
#9 0x4a0c08 in run_argv /home/ahunt/git/git/git.c:781:4
#10 0x49d5a8 in cmd_main /home/ahunt/git/git/git.c:912:19
#11 0x7974da in main /home/ahunt/git/git/common-main.c:52:11
#12 0x7f60e928e349 in __libc_start_main (/lib64/libc.so.6+0x24349)
#13 0x421bd9 in _start /home/abuild/rpmbuild/BUILD/glibc-2.26/csu/../sysdeps/x86_64/start.S:120
Uninitialized value was stored to memory at
#0 0x447eb9 in __msan_memcpy /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/msan/msan_interceptors.cpp:1558:3
#1 0xb4d1e6 in dup_cache_entry /home/ahunt/git/git/read-cache.c:3457:2
#2 0xd214fa in add_entry /home/ahunt/git/git/unpack-trees.c:215:18
#3 0xd1fae0 in keep_entry /home/ahunt/git/git/unpack-trees.c:2276:2
#4 0xd1ff9e in twoway_merge /home/ahunt/git/git/unpack-trees.c:2504:11
#5 0xd27028 in call_unpack_fn /home/ahunt/git/git/unpack-trees.c:593:12
#6 0xd2443d in unpack_nondirectories /home/ahunt/git/git/unpack-trees.c:1106:12
#7 0xd19435 in unpack_callback /home/ahunt/git/git/unpack-trees.c:1306:6
#8 0xd0d7ff in traverse_trees /home/ahunt/git/git/tree-walk.c:532:17
#9 0xd1773a in unpack_trees /home/ahunt/git/git/unpack-trees.c:1683:9
#10 0xdc6370 in checkout /home/ahunt/git/git/merge-ort.c:3590:8
#11 0xdc51c3 in merge_switch_to_result /home/ahunt/git/git/merge-ort.c:3728:7
#12 0xa195a9 in merge_ort_recursive /home/ahunt/git/git/merge-ort-wrappers.c:58:2
#13 0x637fff in try_merge_strategy /home/ahunt/git/git/builtin/merge.c:751:12
#14 0x63057f in cmd_merge /home/ahunt/git/git/builtin/merge.c:1663:9
#15 0x4a1e76 in run_builtin /home/ahunt/git/git/git.c:461:11
#16 0x49e1e7 in handle_builtin /home/ahunt/git/git/git.c:714:3
#17 0x4a0c08 in run_argv /home/ahunt/git/git/git.c:781:4
#18 0x49d5a8 in cmd_main /home/ahunt/git/git/git.c:912:19
#19 0x7974da in main /home/ahunt/git/git/common-main.c:52:11
Uninitialized value was created by a heap allocation
#0 0x44e73d in malloc /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/msan/msan_interceptors.cpp:901:3
#1 0xd592f6 in do_xmalloc /home/ahunt/git/git/wrapper.c:41:8
#2 0xd59248 in xmalloc /home/ahunt/git/git/wrapper.c:62:9
#3 0xa17088 in mem_pool_alloc_block /home/ahunt/git/git/mem-pool.c:22:6
#4 0xa16f78 in mem_pool_init /home/ahunt/git/git/mem-pool.c:44:3
#5 0xb481b8 in load_all_cache_entries /home/ahunt/git/git/read-cache.c
#6 0xb44d40 in do_read_index /home/ahunt/git/git/read-cache.c:2298:17
#7 0xb48a1b in read_index_from /home/ahunt/git/git/read-cache.c:2389:8
#8 0xbd5a0b in repo_read_index /home/ahunt/git/git/repository.c:276:8
#9 0xb4bcaf in repo_read_index_unmerged /home/ahunt/git/git/read-cache.c:3326:2
#10 0x62ed26 in cmd_merge /home/ahunt/git/git/builtin/merge.c:1362:6
#11 0x4a1e76 in run_builtin /home/ahunt/git/git/git.c:461:11
#12 0x49e1e7 in handle_builtin /home/ahunt/git/git/git.c:714:3
#13 0x4a0c08 in run_argv /home/ahunt/git/git/git.c:781:4
#14 0x49d5a8 in cmd_main /home/ahunt/git/git/git.c:912:19
#15 0x7974da in main /home/ahunt/git/git/common-main.c:52:11
#16 0x7f60e928e349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: MemorySanitizer: use-of-uninitialized-value /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/msan/../sanitizer_common/sanitizer_common_interceptors.inc:873:10 in memcmp
Exiting
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
jiangxin
pushed a commit
that referenced
this pull request
Aug 3, 2021
…ints
report_result() sends a struct to the parent process, but that struct
would contain uninitialised padding bytes. Running this code under MSAN
rightly triggers a warning - but we don't particularly care about this
warning because we control the receiving code, and we therefore know
that those padding bytes won't be read on the receiving end.
We could simply suppress this warning under MSAN with the approporiate
ifdef'd attributes, but a less intrusive solution is to 0-initialise the
struct, which guarantees that the padding will also be initialised.
Interestingly, in the error-case branch, we only try to copy the first
two members of pc_item_result, by copying only PC_ITEM_RESULT_BASE_SIZE
bytes. However PC_ITEM_RESULT_BASE_SIZE is defined as
'offsetof(the_last_member)', which means that we're copying padding bytes
after the end of the second last member. We could avoid doing this by
redefining PC_ITEM_RESULT_BASE_SIZE as
'offsetof(second_last_member) + sizeof(second_last_member)', but there's
no huge benefit to doing so (and this patch silences the MSAN warning in
this scenario either way).
MSAN output from t2080 (partially interleaved due to the
parallel work :) ):
Uninitialized bytes in __interceptor_write at offset 12 inside [0x7fff37d83408, 160)
==23279==WARNING: MemorySanitizer: use-of-uninitialized-value
Uninitialized bytes in __interceptor_write at offset 12 inside [0x7ffdb8a07ec8, 160)
==23280==WARNING: MemorySanitizer: use-of-uninitialized-value
#0 0xd5ac28 in xwrite /home/ahunt/git/git/wrapper.c:256:8
#1 0xd5b327 in write_in_full /home/ahunt/git/git/wrapper.c:311:21
#2 0xb0a8c4 in do_packet_write /home/ahunt/git/git/pkt-line.c:221:6
#3 0xb0a5fd in packet_write /home/ahunt/git/git/pkt-line.c:242:6
#4 0x4f7441 in report_result /home/ahunt/git/git/builtin/checkout--worker.c:69:2
#5 0x4f6be6 in worker_loop /home/ahunt/git/git/builtin/checkout--worker.c:100:3
#6 0x4f68d3 in cmd_checkout__worker /home/ahunt/git/git/builtin/checkout--worker.c:143:2
#7 0x4a1e76 in run_builtin /home/ahunt/git/git/git.c:461:11
#8 0x49e1e7 in handle_builtin /home/ahunt/git/git/git.c:714:3
#9 0x4a0c08 in run_argv /home/ahunt/git/git/git.c:781:4
#10 0x49d5a8 in cmd_main /home/ahunt/git/git/git.c:912:19
#11 0x7974da in main /home/ahunt/git/git/common-main.c:52:11
#12 0x7f8778114349 in __libc_start_main (/lib64/libc.so.6+0x24349)
#13 0x421bd9 in _start /home/abuild/rpmbuild/BUILD/glibc-2.26/csu/../sysdeps/x86_64/start.S:120
Uninitialized value was created by an allocation of 'res' in the stack frame of function 'report_result'
#0 0x4f72c0 in report_result /home/ahunt/git/git/builtin/checkout--worker.c:55
SUMMARY: MemorySanitizer: use-of-uninitialized-value /home/ahunt/git/git/wrapper.c:256:8 in xwrite
Exiting
#0 0xd5ac28 in xwrite /home/ahunt/git/git/wrapper.c:256:8
#1 0xd5b327 in write_in_full /home/ahunt/git/git/wrapper.c:311:21
#2 0xb0a8c4 in do_packet_write /home/ahunt/git/git/pkt-line.c:221:6
#3 0xb0a5fd in packet_write /home/ahunt/git/git/pkt-line.c:242:6
#4 0x4f7441 in report_result /home/ahunt/git/git/builtin/checkout--worker.c:69:2
#5 0x4f6be6 in worker_loop /home/ahunt/git/git/builtin/checkout--worker.c:100:3
#6 0x4f68d3 in cmd_checkout__worker /home/ahunt/git/git/builtin/checkout--worker.c:143:2
#7 0x4a1e76 in run_builtin /home/ahunt/git/git/git.c:461:11
#8 0x49e1e7 in handle_builtin /home/ahunt/git/git/git.c:714:3
#9 0x4a0c08 in run_argv /home/ahunt/git/git/git.c:781:4
#10 0x49d5a8 in cmd_main /home/ahunt/git/git/git.c:912:19
#11 0x7974da in main /home/ahunt/git/git/common-main.c:52:11
#12 0x7f2749a0e349 in __libc_start_main (/lib64/libc.so.6+0x24349)
#13 0x421bd9 in _start /home/abuild/rpmbuild/BUILD/glibc-2.26/csu/../sysdeps/x86_64/start.S:120
Uninitialized value was created by an allocation of 'res' in the stack frame of function 'report_result'
#0 0x4f72c0 in report_result /home/ahunt/git/git/builtin/checkout--worker.c:55
SUMMARY: MemorySanitizer: use-of-uninitialized-value /home/ahunt/git/git/wrapper.c:256:8 in xwrite
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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origin starts off pointing to somewhere within line, which is owned by
the caller. Later we might allocate a new string using xmemdupz() or
xstrfmt(). To avoid leaking these new strings, we introduce a to_free
pointer - which allows us to safely free the newly allocated string when
we're done (we cannot just free origin directly as it might still be
pointing to line).
LSAN output from t0090:
Direct leak of 8 byte(s) in 1 object(s) allocated from:
#0 0x49a82d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0xa71f49 in do_xmalloc wrapper.c:41:8
#2 0xa720b0 in do_xmallocz wrapper.c:75:8
#3 0xa720b0 in xmallocz wrapper.c:83:9
#4 0xa720b0 in xmemdupz wrapper.c:99:16
#5 0x8092ba in handle_line fmt-merge-msg.c:187:23
#6 0x8092ba in fmt_merge_msg fmt-merge-msg.c:666:7
#7 0x5ce2e6 in prepare_merge_message builtin/merge.c:1119:2
#8 0x5ce2e6 in collect_parents builtin/merge.c:1215:3
#9 0x5c9c1e in cmd_merge builtin/merge.c:1454:16
#10 0x4ce83e in run_builtin git.c:475:11
#11 0x4ccafe in handle_builtin git.c:729:3
#12 0x4cb01c in run_argv git.c:818:4
#13 0x4cb01c in cmd_main git.c:949:19
#14 0x6b3fad in main common-main.c:52:11
#15 0x7fb929620349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 8 byte(s) leaked in 1 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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realpath is only populated if we execute the git_work_tree_initialized
block. However that block also causes us to return early, meaning we
never actually release the strbuf in the case where we populated it.
Therefore we move all strbuf related code into the block to guarantee
that we can't leak it.
LSAN output from t0095:
Direct leak of 129 byte(s) in 1 object(s) allocated from:
#0 0x49a9b9 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0x78f585 in xrealloc wrapper.c:126:8
#2 0x713ff4 in strbuf_grow strbuf.c:98:2
#3 0x713ff4 in strbuf_getcwd strbuf.c:597:3
#4 0x4f0c18 in strbuf_realpath_1 abspath.c:99:7
#5 0x5ae4a4 in set_git_work_tree environment.c:259:3
#6 0x6fdd8a in setup_discovered_git_dir setup.c:931:2
#7 0x6fdd8a in setup_git_directory_gently setup.c:1235:12
#8 0x4cb50d in get_bloom_filter_for_commit t/helper/test-bloom.c:41:2
#9 0x4cb50d in cmd__bloom t/helper/test-bloom.c:95:3
#10 0x4caa1f in cmd_main t/helper/test-tool.c:124:11
#11 0x4caded in main common-main.c:52:11
#12 0x7f0869f02349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 129 byte(s) leaked in 1 allocation(s).
It looks like this leak has existed since realpath was first added to
set_git_work_tree() in:
3d7747e (real_path: remove unsafe API, 2020-03-10)
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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relative_url() populates sb. In the normal return path, its buffer is
detached using strbuf_detach(). However the early return path does
nothing with sb, which means that sb's memory is leaked - therefore
we add a release to avoid this leak.
The reset is also only necessary for the normal return path, hence we
move it down to after the early-return to avoid unnecessary work.
LSAN output from t0060:
Direct leak of 121 byte(s) in 1 object(s) allocated from:
#0 0x7f31246f28b0 in realloc (/usr/lib64/libasan.so.4+0xdc8b0)
#1 0x98d7d6 in xrealloc wrapper.c:126
#2 0x909a60 in strbuf_grow strbuf.c:98
#3 0x90bf00 in strbuf_vaddf strbuf.c:401
#4 0x90c321 in strbuf_addf strbuf.c:335
#5 0x5cb78d in relative_url builtin/submodule--helper.c:182
#6 0x5cbe46 in resolve_relative_url_test builtin/submodule--helper.c:248
#7 0x410dcd in run_builtin git.c:475
#8 0x410dcd in handle_builtin git.c:729
#9 0x414087 in run_argv git.c:818
#10 0x414087 in cmd_main git.c:949
#11 0x40e9ec in main common-main.c:52
#12 0x7f3123c41349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 121 byte(s) leaked in 1 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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cmd_for_each_repo() copies argv into args (a strvec), which is later
passed into run_command_on_repo(), which in turn copies that strvec onto
the end of child.args. The initial copy is unnecessary (we never modify
args). We therefore choose to just pass argv directly into
run_command_on_repo(), which lets us avoid the copy and fixes the leak.
LSAN output from t0068:
Direct leak of 192 byte(s) in 1 object(s) allocated from:
#0 0x7f63bd4ab8b0 in realloc (/usr/lib64/libasan.so.4+0xdc8b0)
#1 0x98d7e6 in xrealloc wrapper.c:126
#2 0x916914 in strvec_push_nodup strvec.c:19
#3 0x916a6e in strvec_push strvec.c:26
#4 0x4be4eb in cmd_for_each_repo builtin/for-each-repo.c:49
#5 0x410dcd in run_builtin git.c:475
#6 0x410dcd in handle_builtin git.c:729
#7 0x414087 in run_argv git.c:818
#8 0x414087 in cmd_main git.c:949
#9 0x40e9ec in main common-main.c:52
#10 0x7f63bc9fa349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 22 byte(s) in 2 object(s) allocated from:
#0 0x7f63bd445e30 in __interceptor_strdup (/usr/lib64/libasan.so.4+0x76e30)
#1 0x98d698 in xstrdup wrapper.c:29
#2 0x916a63 in strvec_push strvec.c:26
#3 0x4be4eb in cmd_for_each_repo builtin/for-each-repo.c:49
#4 0x410dcd in run_builtin git.c:475
#5 0x410dcd in handle_builtin git.c:729
#6 0x414087 in run_argv git.c:818
#7 0x414087 in cmd_main git.c:949
#8 0x40e9ec in main common-main.c:52
#9 0x7f63bc9fa349 in __libc_start_main (/lib64/libc.so.6+0x24349)
See also discussion about the original implementation below - this code
appears to have evolved from a callback explaining the double-strvec-copy
pattern, but there's no strong reason to keep that now:
https://lore.kernel.org/git/68bbeca5-314b-08ee-ef36-040e3f3814e9@gmail.com/
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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old_dir/new_dir are free()'d at the end of update_dir_rename_counts, however if we return early we'll never free those strings. Therefore we should move all new allocations after the possible early return, avoiding a leak. This seems like a fairly recent leak, that started happening since the early-return was added in: 1ad69eb (diffcore-rename: compute dir_rename_counts in stages, 2021-02-27) LSAN output from t0022: Direct leak of 7 byte(s) in 1 object(s) allocated from: #0 0x486804 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3 #1 0xa71e48 in xstrdup wrapper.c:29:14 #2 0x7db9c7 in update_dir_rename_counts diffcore-rename.c:464:12 #3 0x7db6ae in find_renames diffcore-rename.c:1062:3 #4 0x7d76c3 in diffcore_rename_extended diffcore-rename.c:1472:18 #5 0x7b4cfc in diffcore_std diff.c:6705:4 #6 0x855e46 in log_tree_diff_flush log-tree.c:846:2 #7 0x856574 in log_tree_diff log-tree.c:955:3 #8 0x856574 in log_tree_commit log-tree.c:986:10 #9 0x9a9c67 in print_commit_summary sequencer.c:1329:7 #10 0x52e623 in cmd_commit builtin/commit.c:1862:3 #11 0x4ce83e in run_builtin git.c:475:11 #12 0x4ccafe in handle_builtin git.c:729:3 #13 0x4cb01c in run_argv git.c:818:4 #14 0x4cb01c in cmd_main git.c:949:19 #15 0x6b3f3d in main common-main.c:52:11 #16 0x7fe397c7a349 in __libc_start_main (/lib64/libc.so.6+0x24349) Direct leak of 7 byte(s) in 1 object(s) allocated from: #0 0x486804 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3 #1 0xa71e48 in xstrdup wrapper.c:29:14 #2 0x7db9bc in update_dir_rename_counts diffcore-rename.c:463:12 #3 0x7db6ae in find_renames diffcore-rename.c:1062:3 #4 0x7d76c3 in diffcore_rename_extended diffcore-rename.c:1472:18 #5 0x7b4cfc in diffcore_std diff.c:6705:4 #6 0x855e46 in log_tree_diff_flush log-tree.c:846:2 #7 0x856574 in log_tree_diff log-tree.c:955:3 #8 0x856574 in log_tree_commit log-tree.c:986:10 #9 0x9a9c67 in print_commit_summary sequencer.c:1329:7 #10 0x52e623 in cmd_commit builtin/commit.c:1862:3 #11 0x4ce83e in run_builtin git.c:475:11 #12 0x4ccafe in handle_builtin git.c:729:3 #13 0x4cb01c in run_argv git.c:818:4 #14 0x4cb01c in cmd_main git.c:949:19 #15 0x6b3f3d in main common-main.c:52:11 #16 0x7fe397c7a349 in __libc_start_main (/lib64/libc.so.6+0x24349) SUMMARY: AddressSanitizer: 14 byte(s) leaked in 2 allocation(s). Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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u.head is populated using resolve_refdup(), which returns a newly
allocated string - hence we also need to free() it.
Found while running t0041 with LSAN:
Direct leak of 16 byte(s) in 1 object(s) allocated from:
#0 0x486804 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
#1 0xa8be98 in xstrdup wrapper.c:29:14
#2 0x9481db in head_atom_parser ref-filter.c:549:17
#3 0x9408c7 in parse_ref_filter_atom ref-filter.c:703:30
#4 0x9400e3 in verify_ref_format ref-filter.c:974:8
#5 0x4f9e8b in print_ref_list builtin/branch.c:439:6
#6 0x4f9e8b in cmd_branch builtin/branch.c:757:3
#7 0x4ce83e in run_builtin git.c:475:11
#8 0x4ccafe in handle_builtin git.c:729:3
#9 0x4cb01c in run_argv git.c:818:4
#10 0x4cb01c in cmd_main git.c:949:19
#11 0x6bdc2d in main common-main.c:52:11
#12 0x7f96edf86349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 16 byte(s) leaked in 1 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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repo_diff_setup() calls through to diff.c's static prep_parse_options(),
which in turn allocates a new array into diff_opts.parseopts.
diff_setup_done() is responsible for freeing that array, and has the
benefit of verifying diff_opts too - hence we add a call to
diff_setup_done() to avoid leaking parseopts.
Output from the leak as found while running t0090 with LSAN:
Direct leak of 7120 byte(s) in 1 object(s) allocated from:
#0 0x49a82d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0xa8bf89 in do_xmalloc wrapper.c:41:8
#2 0x7a7bae in prep_parse_options diff.c:5636:2
#3 0x7a7bae in repo_diff_setup diff.c:4611:2
#4 0x93716c in repo_index_has_changes read-cache.c:2518:3
#5 0x872233 in unclean merge-ort-wrappers.c:12:14
#6 0x872233 in merge_ort_recursive merge-ort-wrappers.c:53:6
#7 0x5d5b11 in try_merge_strategy builtin/merge.c:752:12
#8 0x5d0b6b in cmd_merge builtin/merge.c:1666:9
#9 0x4ce83e in run_builtin git.c:475:11
#10 0x4ccafe in handle_builtin git.c:729:3
#11 0x4cb01c in run_argv git.c:818:4
#12 0x4cb01c in cmd_main git.c:949:19
#13 0x6bdc2d in main common-main.c:52:11
#14 0x7f551eb51349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 7120 byte(s) leaked in 1 allocation(s)
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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apply_multi_file_filter and async_query_available_blobs both query
subprocess output using subprocess_read_status, which writes data into
the identically named filter_status strbuf. We add a strbuf_release to
avoid leaking their contents.
Leak output seen when running t0021 with LSAN:
Direct leak of 24 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa8c2b5 in xrealloc wrapper.c:126:8
#2 0x9ff99d in strbuf_grow strbuf.c:98:2
#3 0x9ff99d in strbuf_addbuf strbuf.c:304:2
#4 0xa101d6 in subprocess_read_status sub-process.c:45:5
#5 0x77793c in apply_multi_file_filter convert.c:886:8
#6 0x77793c in apply_filter convert.c:1042:10
#7 0x77a0b5 in convert_to_git_filter_fd convert.c:1492:7
#8 0x8b48cd in index_stream_convert_blob object-file.c:2156:2
#9 0x8b48cd in index_fd object-file.c:2248:9
#10 0x597411 in hash_fd builtin/hash-object.c:43:9
#11 0x596be1 in hash_object builtin/hash-object.c:59:2
#12 0x596be1 in cmd_hash_object builtin/hash-object.c:153:3
#13 0x4ce83e in run_builtin git.c:475:11
#14 0x4ccafe in handle_builtin git.c:729:3
#15 0x4cb01c in run_argv git.c:818:4
#16 0x4cb01c in cmd_main git.c:949:19
#17 0x6bdc2d in main common-main.c:52:11
#18 0x7f42acf79349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 24 byte(s) leaked in 1 allocation(s).
Direct leak of 120 byte(s) in 5 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa8c295 in xrealloc wrapper.c:126:8
#2 0x9ff97d in strbuf_grow strbuf.c:98:2
#3 0x9ff97d in strbuf_addbuf strbuf.c:304:2
#4 0xa101b6 in subprocess_read_status sub-process.c:45:5
#5 0x775c73 in async_query_available_blobs convert.c:960:8
#6 0x80029d in finish_delayed_checkout entry.c:183:9
#7 0xa65d1e in check_updates unpack-trees.c:493:10
#8 0xa5f469 in unpack_trees unpack-trees.c:1747:8
#9 0x525971 in checkout builtin/clone.c:815:6
#10 0x525971 in cmd_clone builtin/clone.c:1409:8
#11 0x4ce83e in run_builtin git.c:475:11
#12 0x4ccafe in handle_builtin git.c:729:3
#13 0x4cb01c in run_argv git.c:818:4
#14 0x4cb01c in cmd_main git.c:949:19
#15 0x6bdc2d in main common-main.c:52:11
#16 0x7fa253fce349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 120 byte(s) leaked in 5 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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These leaks all happen at the end of cmd_mv, hence don't matter in any
way. But we still fix the easy ones and squash the rest to get us closer
to being able to run tests without leaks.
LSAN output from t0050:
Direct leak of 384 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa8c015 in xrealloc wrapper.c:126:8
#2 0xa0a7e1 in add_entry string-list.c:44:2
#3 0xa0a7e1 in string_list_insert string-list.c:58:14
#4 0x5dac03 in cmd_mv builtin/mv.c:248:4
#5 0x4ce83e in run_builtin git.c:475:11
#6 0x4ccafe in handle_builtin git.c:729:3
#7 0x4cb01c in run_argv git.c:818:4
#8 0x4cb01c in cmd_main git.c:949:19
#9 0x6bd9ad in main common-main.c:52:11
#10 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Direct leak of 16 byte(s) in 1 object(s) allocated from:
#0 0x49a82d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0xa8bd09 in do_xmalloc wrapper.c:41:8
#2 0x5dbc34 in internal_prefix_pathspec builtin/mv.c:32:2
#3 0x5da575 in cmd_mv builtin/mv.c:158:14
#4 0x4ce83e in run_builtin git.c:475:11
#5 0x4ccafe in handle_builtin git.c:729:3
#6 0x4cb01c in run_argv git.c:818:4
#7 0x4cb01c in cmd_main git.c:949:19
#8 0x6bd9ad in main common-main.c:52:11
#9 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Direct leak of 16 byte(s) in 1 object(s) allocated from:
#0 0x49a82d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0xa8bd09 in do_xmalloc wrapper.c:41:8
#2 0x5dbc34 in internal_prefix_pathspec builtin/mv.c:32:2
#3 0x5da4e4 in cmd_mv builtin/mv.c:148:11
#4 0x4ce83e in run_builtin git.c:475:11
#5 0x4ccafe in handle_builtin git.c:729:3
#6 0x4cb01c in run_argv git.c:818:4
#7 0x4cb01c in cmd_main git.c:949:19
#8 0x6bd9ad in main common-main.c:52:11
#9 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Direct leak of 8 byte(s) in 1 object(s) allocated from:
#0 0x49a9a2 in calloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
#1 0xa8c119 in xcalloc wrapper.c:140:8
#2 0x5da585 in cmd_mv builtin/mv.c:159:22
#3 0x4ce83e in run_builtin git.c:475:11
#4 0x4ccafe in handle_builtin git.c:729:3
#5 0x4cb01c in run_argv git.c:818:4
#6 0x4cb01c in cmd_main git.c:949:19
#7 0x6bd9ad in main common-main.c:52:11
#8 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Direct leak of 4 byte(s) in 1 object(s) allocated from:
#0 0x49a9a2 in calloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
#1 0xa8c119 in xcalloc wrapper.c:140:8
#2 0x5da4f8 in cmd_mv builtin/mv.c:149:10
#3 0x4ce83e in run_builtin git.c:475:11
#4 0x4ccafe in handle_builtin git.c:729:3
#5 0x4cb01c in run_argv git.c:818:4
#6 0x4cb01c in cmd_main git.c:949:19
#7 0x6bd9ad in main common-main.c:52:11
#8 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 65 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa8c015 in xrealloc wrapper.c:126:8
#2 0xa00226 in strbuf_grow strbuf.c:98:2
#3 0xa00226 in strbuf_vaddf strbuf.c:394:3
#4 0xa065c7 in xstrvfmt strbuf.c:981:2
#5 0xa065c7 in xstrfmt strbuf.c:991:8
#6 0x9e7ce7 in prefix_path_gently setup.c:115:15
#7 0x9e7fa6 in prefix_path setup.c:128:12
#8 0x5dbdbf in internal_prefix_pathspec builtin/mv.c:55:23
#9 0x5da575 in cmd_mv builtin/mv.c:158:14
#10 0x4ce83e in run_builtin git.c:475:11
#11 0x4ccafe in handle_builtin git.c:729:3
#12 0x4cb01c in run_argv git.c:818:4
#13 0x4cb01c in cmd_main git.c:949:19
#14 0x6bd9ad in main common-main.c:52:11
#15 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 65 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa8c015 in xrealloc wrapper.c:126:8
#2 0xa00226 in strbuf_grow strbuf.c:98:2
#3 0xa00226 in strbuf_vaddf strbuf.c:394:3
#4 0xa065c7 in xstrvfmt strbuf.c:981:2
#5 0xa065c7 in xstrfmt strbuf.c:991:8
#6 0x9e7ce7 in prefix_path_gently setup.c:115:15
#7 0x9e7fa6 in prefix_path setup.c:128:12
#8 0x5dbdbf in internal_prefix_pathspec builtin/mv.c:55:23
#9 0x5da4e4 in cmd_mv builtin/mv.c:148:11
#10 0x4ce83e in run_builtin git.c:475:11
#11 0x4ccafe in handle_builtin git.c:729:3
#12 0x4cb01c in run_argv git.c:818:4
#13 0x4cb01c in cmd_main git.c:949:19
#14 0x6bd9ad in main common-main.c:52:11
#15 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 558 byte(s) leaked in 7 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
jiangxin
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that referenced
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Aug 13, 2021
merge_name() calls dwim_ref(), which allocates a new string into
found_ref. Therefore add a free() to avoid leaking found_ref.
LSAN output from t0021:
Direct leak of 16 byte(s) in 1 object(s) allocated from:
#0 0x486804 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
#1 0xa8beb8 in xstrdup wrapper.c:29:14
#2 0x954054 in expand_ref refs.c:671:12
#3 0x953cb6 in repo_dwim_ref refs.c:644:22
#4 0x5d3759 in dwim_ref refs.h:162:9
#5 0x5d3759 in merge_name builtin/merge.c:517:6
#6 0x5d3759 in collect_parents builtin/merge.c:1214:5
#7 0x5cf60d in cmd_merge builtin/merge.c:1458:16
#8 0x4ce83e in run_builtin git.c:475:11
#9 0x4ccafe in handle_builtin git.c:729:3
#10 0x4cb01c in run_argv git.c:818:4
#11 0x4cb01c in cmd_main git.c:949:19
#12 0x6bdbfd in main common-main.c:52:11
#13 0x7f0430502349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 16 byte(s) leaked in 1 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
jiangxin
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Aug 13, 2021
- cmd_rebase populates rebase_options.strategy with newly allocated
strings, hence we need to free those strings at the end of cmd_rebase
to avoid a leak.
- In some cases: get_replay_opts() is called, which prepares replay_opts
using data from rebase_options. We used to simply copy the pointer
from rebase_options.strategy, however that would now result in a
double-free because sequencer_remove_state() is eventually used to
free replay_opts.strategy. To avoid this we xstrdup() strategy when
adding it to replay_opts.
The original leak happens because we always populate
rebase_options.strategy, but we don't always enter the path that calls
get_replay_opts() and later sequencer_remove_state() - in other words
we'd always allocate a new string into rebase_options.strategy but
only sometimes did we free it. We now make sure that rebase_options
and replay_opts both own their own copies of strategy, and each copy
is free'd independently.
This was first seen when running t0021 with LSAN, but t2012 helped catch
the fact that we can't just free(options.strategy) at the end of
cmd_rebase (as that can cause a double-free). LSAN output from t0021:
LSAN output from t0021:
Direct leak of 4 byte(s) in 1 object(s) allocated from:
#0 0x486804 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
#1 0xa71eb8 in xstrdup wrapper.c:29:14
#2 0x61b1cc in cmd_rebase builtin/rebase.c:1779:22
#3 0x4ce83e in run_builtin git.c:475:11
#4 0x4ccafe in handle_builtin git.c:729:3
#5 0x4cb01c in run_argv git.c:818:4
#6 0x4cb01c in cmd_main git.c:949:19
#7 0x6b3fad in main common-main.c:52:11
#8 0x7f267b512349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 4 byte(s) leaked in 1 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
jiangxin
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that referenced
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Aug 13, 2021
setup_unpack_trees_porcelain() populates various fields on
unpack_tree_opts, we need to call clear_unpack_trees_porcelain() to
avoid leaking them. Specifically, we used to leak
unpack_tree_opts.msgs_to_free.
We have to do this in leave_reset_head because there are multiple
scenarios where unpack_tree_opts has already been configured, followed
by a 'goto leave_reset_head'. But we can also 'goto leave_reset_head'
prior to having initialised unpack_tree_opts via memset(..., 0, ...).
Therefore we also move unpack_tree_opts initialisation to the start of
reset_head(), and convert it to use brace initialisation - which
guarantees that we can never clear an uninitialised unpack_tree_opts.
clear_unpack_tree_opts() is always safe to call as long as
unpack_tree_opts is at least zero-initialised, i.e. it does not depend
on a previous call to setup_unpack_trees_porcelain().
LSAN output from t0021:
Direct leak of 192 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa721e5 in xrealloc wrapper.c:126:8
#2 0x9f7861 in strvec_push_nodup strvec.c:19:2
#3 0x9f7861 in strvec_pushf strvec.c:39:2
#4 0xa43e14 in setup_unpack_trees_porcelain unpack-trees.c:129:3
#5 0x97e011 in reset_head reset.c:53:2
#6 0x61dfa5 in cmd_rebase builtin/rebase.c:1991:9
#7 0x4ce83e in run_builtin git.c:475:11
#8 0x4ccafe in handle_builtin git.c:729:3
#9 0x4cb01c in run_argv git.c:818:4
#10 0x4cb01c in cmd_main git.c:949:19
#11 0x6b3f3d in main common-main.c:52:11
#12 0x7fa8addf3349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 147 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa721e5 in xrealloc wrapper.c:126:8
#2 0x9e8d54 in strbuf_grow strbuf.c:98:2
#3 0x9e8d54 in strbuf_vaddf strbuf.c:401:3
#4 0x9f7774 in strvec_pushf strvec.c:36:2
#5 0xa43e14 in setup_unpack_trees_porcelain unpack-trees.c:129:3
#6 0x97e011 in reset_head reset.c:53:2
#7 0x61dfa5 in cmd_rebase builtin/rebase.c:1991:9
#8 0x4ce83e in run_builtin git.c:475:11
#9 0x4ccafe in handle_builtin git.c:729:3
#10 0x4cb01c in run_argv git.c:818:4
#11 0x4cb01c in cmd_main git.c:949:19
#12 0x6b3f3d in main common-main.c:52:11
#13 0x7fa8addf3349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 134 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa721e5 in xrealloc wrapper.c:126:8
#2 0x9e8d54 in strbuf_grow strbuf.c:98:2
#3 0x9e8d54 in strbuf_vaddf strbuf.c:401:3
#4 0x9f7774 in strvec_pushf strvec.c:36:2
#5 0xa43fe4 in setup_unpack_trees_porcelain unpack-trees.c:168:3
#6 0x97e011 in reset_head reset.c:53:2
#7 0x61dfa5 in cmd_rebase builtin/rebase.c:1991:9
#8 0x4ce83e in run_builtin git.c:475:11
#9 0x4ccafe in handle_builtin git.c:729:3
#10 0x4cb01c in run_argv git.c:818:4
#11 0x4cb01c in cmd_main git.c:949:19
#12 0x6b3f3d in main common-main.c:52:11
#13 0x7fa8addf3349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 130 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa721e5 in xrealloc wrapper.c:126:8
#2 0x9e8d54 in strbuf_grow strbuf.c:98:2
#3 0x9e8d54 in strbuf_vaddf strbuf.c:401:3
#4 0x9f7774 in strvec_pushf strvec.c:36:2
#5 0xa43f20 in setup_unpack_trees_porcelain unpack-trees.c:150:3
#6 0x97e011 in reset_head reset.c:53:2
#7 0x61dfa5 in cmd_rebase builtin/rebase.c:1991:9
#8 0x4ce83e in run_builtin git.c:475:11
#9 0x4ccafe in handle_builtin git.c:729:3
#10 0x4cb01c in run_argv git.c:818:4
#11 0x4cb01c in cmd_main git.c:949:19
#12 0x6b3f3d in main common-main.c:52:11
#13 0x7fa8addf3349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 603 byte(s) leaked in 4 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
jiangxin
pushed a commit
that referenced
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Oct 30, 2021
In a sparse index it is possible for the tree that is being verified
to be freed while it is being verified. This happens when the index is
sparse but the cache tree is not and index_name_pos() looks up a path
from the cache tree that is a descendant of a sparse index entry. That
triggers a call to ensure_full_index() which frees the cache tree that
is being verified. Carrying on trying to verify the tree after this
results in a use-after-free bug. Instead restart the verification if a
sparse index is converted to a full index. This bug is triggered by a
call to reset_head() in "git rebase --apply". Thanks to René Scharfe
and Derrick Stolee for their help analyzing the problem.
==74345==ERROR: AddressSanitizer: heap-use-after-free on address 0x606000001b20 at pc 0x557cbe82d3a2 bp 0x7ffdfee08090 sp 0x7ffdfee08080
READ of size 4 at 0x606000001b20 thread T0
#0 0x557cbe82d3a1 in verify_one /home/phil/src/git/cache-tree.c:863
#1 0x557cbe82ca9d in verify_one /home/phil/src/git/cache-tree.c:840
#2 0x557cbe82ca9d in verify_one /home/phil/src/git/cache-tree.c:840
#3 0x557cbe82ca9d in verify_one /home/phil/src/git/cache-tree.c:840
#4 0x557cbe830a2b in cache_tree_verify /home/phil/src/git/cache-tree.c:910
#5 0x557cbea53741 in write_locked_index /home/phil/src/git/read-cache.c:3250
#6 0x557cbeab7fdd in reset_head /home/phil/src/git/reset.c:87
#7 0x557cbe72147f in cmd_rebase builtin/rebase.c:2074
#8 0x557cbe5bd151 in run_builtin /home/phil/src/git/git.c:461
#9 0x557cbe5bd151 in handle_builtin /home/phil/src/git/git.c:714
#10 0x557cbe5c0503 in run_argv /home/phil/src/git/git.c:781
#11 0x557cbe5c0503 in cmd_main /home/phil/src/git/git.c:912
#12 0x557cbe5bad28 in main /home/phil/src/git/common-main.c:52
#13 0x7fdd4b82eb24 in __libc_start_main (/usr/lib/libc.so.6+0x27b24)
#14 0x557cbe5bcb8d in _start (/home/phil/src/git/git+0x1b9b8d)
0x606000001b20 is located 0 bytes inside of 56-byte region [0x606000001b20,0x606000001b58)
freed by thread T0 here:
#0 0x7fdd4bacff19 in __interceptor_free /build/gcc/src/gcc/libsanitizer/asan/asan_malloc_linux.cpp:127
#1 0x557cbe82af60 in cache_tree_free /home/phil/src/git/cache-tree.c:35
#2 0x557cbe82aee5 in cache_tree_free /home/phil/src/git/cache-tree.c:31
#3 0x557cbe82aee5 in cache_tree_free /home/phil/src/git/cache-tree.c:31
#4 0x557cbe82aee5 in cache_tree_free /home/phil/src/git/cache-tree.c:31
#5 0x557cbeb2557a in ensure_full_index /home/phil/src/git/sparse-index.c:310
#6 0x557cbea45c4a in index_name_stage_pos /home/phil/src/git/read-cache.c:588
#7 0x557cbe82ce37 in verify_one /home/phil/src/git/cache-tree.c:850
#8 0x557cbe82ca9d in verify_one /home/phil/src/git/cache-tree.c:840
#9 0x557cbe82ca9d in verify_one /home/phil/src/git/cache-tree.c:840
#10 0x557cbe82ca9d in verify_one /home/phil/src/git/cache-tree.c:840
#11 0x557cbe830a2b in cache_tree_verify /home/phil/src/git/cache-tree.c:910
#12 0x557cbea53741 in write_locked_index /home/phil/src/git/read-cache.c:3250
#13 0x557cbeab7fdd in reset_head /home/phil/src/git/reset.c:87
#14 0x557cbe72147f in cmd_rebase builtin/rebase.c:2074
#15 0x557cbe5bd151 in run_builtin /home/phil/src/git/git.c:461
#16 0x557cbe5bd151 in handle_builtin /home/phil/src/git/git.c:714
#17 0x557cbe5c0503 in run_argv /home/phil/src/git/git.c:781
#18 0x557cbe5c0503 in cmd_main /home/phil/src/git/git.c:912
#19 0x557cbe5bad28 in main /home/phil/src/git/common-main.c:52
#20 0x7fdd4b82eb24 in __libc_start_main (/usr/lib/libc.so.6+0x27b24)
previously allocated by thread T0 here:
#0 0x7fdd4bad0459 in __interceptor_calloc /build/gcc/src/gcc/libsanitizer/asan/asan_malloc_linux.cpp:154
#1 0x557cbebc1807 in xcalloc /home/phil/src/git/wrapper.c:140
#2 0x557cbe82b7d8 in cache_tree /home/phil/src/git/cache-tree.c:17
#3 0x557cbe82b7d8 in prime_cache_tree_rec /home/phil/src/git/cache-tree.c:763
#4 0x557cbe82b837 in prime_cache_tree_rec /home/phil/src/git/cache-tree.c:764
#5 0x557cbe82b837 in prime_cache_tree_rec /home/phil/src/git/cache-tree.c:764
#6 0x557cbe8304e1 in prime_cache_tree /home/phil/src/git/cache-tree.c:779
#7 0x557cbeab7fa7 in reset_head /home/phil/src/git/reset.c:85
#8 0x557cbe72147f in cmd_rebase builtin/rebase.c:2074
#9 0x557cbe5bd151 in run_builtin /home/phil/src/git/git.c:461
#10 0x557cbe5bd151 in handle_builtin /home/phil/src/git/git.c:714
#11 0x557cbe5c0503 in run_argv /home/phil/src/git/git.c:781
#12 0x557cbe5c0503 in cmd_main /home/phil/src/git/git.c:912
#13 0x557cbe5bad28 in main /home/phil/src/git/common-main.c:52
#14 0x7fdd4b82eb24 in __libc_start_main (/usr/lib/libc.so.6+0x27b24)
Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
jiangxin
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Jan 17, 2022
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>
jiangxin
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Apr 6, 2022
Add "fast_unwind_on_malloc=0" to LSAN_OPTIONS to get more meaningful
stack traces from LSAN. This isn't required under ASAN which will emit
traces such as this one for a leak in "t/t0006-date.sh":
$ ASAN_OPTIONS=detect_leaks=1 ./t0006-date.sh -vixd
[...]
Direct leak of 3 byte(s) in 1 object(s) allocated from:
#0 0x488b94 in strdup (t/helper/test-tool+0x488b94)
#1 0x9444a4 in xstrdup wrapper.c:29:14
#2 0x5995fa in parse_date_format date.c:991:24
#3 0x4d2056 in show_dates t/helper/test-date.c:39:2
#4 0x4d174a in cmd__date t/helper/test-date.c:116:3
#5 0x4cce89 in cmd_main t/helper/test-tool.c:127:11
#6 0x4cd1e3 in main common-main.c:52:11
#7 0x7fef3c695e49 in __libc_start_main csu/../csu/libc-start.c:314:16
#8 0x422b09 in _start (t/helper/test-tool+0x422b09)
SUMMARY: AddressSanitizer: 3 byte(s) leaked in 1 allocation(s).
Aborted
Whereas LSAN would emit this instead:
$ ./t0006-date.sh -vixd
[...]
Direct leak of 3 byte(s) in 1 object(s) allocated from:
#0 0x4323b8 in malloc (t/helper/test-tool+0x4323b8)
#1 0x7f2be1d614aa in strdup string/strdup.c:42:15
SUMMARY: LeakSanitizer: 3 byte(s) leaked in 1 allocation(s).
Aborted
Now we'll instead git this sensible stack trace under
LSAN. I.e. almost the same one (but starting with "malloc", as is
usual for LSAN) as under ASAN:
Direct leak of 3 byte(s) in 1 object(s) allocated from:
#0 0x4323b8 in malloc (t/helper/test-tool+0x4323b8)
#1 0x7f012af5c4aa in strdup string/strdup.c:42:15
#2 0x5cb164 in xstrdup wrapper.c:29:14
#3 0x495ee9 in parse_date_format date.c:991:24
#4 0x453aac in show_dates t/helper/test-date.c:39:2
#5 0x453782 in cmd__date t/helper/test-date.c:116:3
#6 0x451d95 in cmd_main t/helper/test-tool.c:127:11
#7 0x451f1e in main common-main.c:52:11
#8 0x7f012aef5e49 in __libc_start_main csu/../csu/libc-start.c:314:16
#9 0x42e0a9 in _start (t/helper/test-tool+0x42e0a9)
SUMMARY: LeakSanitizer: 3 byte(s) leaked in 1 allocation(s).
Aborted
As the option name suggests this does make things slower, e.g. for
t0001-init.sh we're around 10% slower:
$ hyperfine -L v 0,1 'LSAN_OPTIONS=fast_unwind_on_malloc={v} make T=t0001-init.sh' -r 3
Benchmark 1: LSAN_OPTIONS=fast_unwind_on_malloc=0 make T=t0001-init.sh
Time (mean ± σ): 2.135 s ± 0.015 s [User: 1.951 s, System: 0.554 s]
Range (min … max): 2.122 s … 2.152 s 3 runs
Benchmark 2: LSAN_OPTIONS=fast_unwind_on_malloc=1 make T=t0001-init.sh
Time (mean ± σ): 1.981 s ± 0.055 s [User: 1.769 s, System: 0.488 s]
Range (min … max): 1.941 s … 2.044 s 3 runs
Summary
'LSAN_OPTIONS=fast_unwind_on_malloc=1 make T=t0001-init.sh' ran
1.08 ± 0.03 times faster than 'LSAN_OPTIONS=fast_unwind_on_malloc=0 make T=t0001-init.sh'
I think that's more than worth it to get the more meaningful stack
traces, we can always provide LSAN_OPTIONS=fast_unwind_on_malloc=0 for
one-off "fast" runs.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
jiangxin
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that referenced
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Apr 6, 2022
Add a failing test which demonstrates a regression in a18d66c ("diff.c: free "buf" in diff_words_flush()", 2022-03-04), the regression is discussed in detail in the subsequent commit. With it running `git show --word-diff --color-moved` with SANITIZE=address would emit: ==31191==ERROR: AddressSanitizer: attempting double-free on 0x617000021100 in thread T0: #0 0x49f0a2 in free (git+0x49f0a2) #1 0x9b0e4d in diff_words_flush diff.c:2153:3 #2 0x9aed5d in fn_out_consume diff.c:2354:3 #3 0xe092ab in consume_one xdiff-interface.c:43:9 #4 0xe072eb in xdiff_outf xdiff-interface.c:76:10 #5 0xec7014 in xdl_emit_diffrec xdiff/xutils.c:53:6 [...] 0x617000021100 is located 0 bytes inside of 768-byte region [0x617000021100,0x617000021400) freed by thread T0 here: #0 0x49f0a2 in free (git+0x49f0a2) [...(same stacktrace)...] previously allocated by thread T0 here: #0 0x49f603 in __interceptor_realloc (git+0x49f603) #1 0xde4da4 in xrealloc wrapper.c:126:8 #2 0x995dc5 in append_emitted_diff_symbol diff.c:794:2 #3 0x96c44a in emit_diff_symbol diff.c:1527:3 [...] This was not caught by the test suite because we test `diff --word-diff --color-moved` only so far. Therefore, add a test for `show`, too. Signed-off-by: Michael J Gruber <git@grubix.eu> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Update Simplified Chinese translation with the new "po/git.pot"
Signed-off-by: Jiang Xin worldhello.net@gmail.com