[PATCH 0/7] Fix all leaks in t0001

From: "Andrzej Hunt via GitGitGadget" <gitgitgadget@gmail.com>
To: git@vger.kernel.org
Cc: Andrzej Hunt <andrzej@ahunt.org>
Subject: [PATCH 0/7] Fix all leaks in t0001
Date: Mon, 08 Mar 2021 18:36:13 +0000	[thread overview]
Message-ID: <pull.899.git.1615228580.gitgitgadget@gmail.com> (raw)

This series fixes (or annotates) all the memory leaks that can cause t0001
to fail when run with LeakSanitizer (t0000 already passes without failures).

I suspect that none of these leaks had any user impact, and I'm aware that
every change does cause some noise - I would have no objections to
abandoning this series if it's not deemed valuable enough. On the other
hand: fixing or suppressing these leaks should make it easier to spot leaks
that have more significant user impact (it's entirely plausible that no real
impactful leaks exist).

Note: this series does not guarantee that there are no leaks within
t0000-t0001, it only fixes those leaks which cause test failures. There is
at least one test case in t0000 where git is invoked in a subshell, and the
return value is ignored - meaning that a memory leak that is occuring during
that invocation does not cause tests to fail (I'm still trying to figure out
if that's something that's worth fixing - but that's probably a topic for a
separate thread):
https://git.kernel.org/pub/scm/git/git.git/tree/t/t0000-basic.sh#n1285

In case anyone is interested: I have been using the following workflow to
find leaks and verify fixes - I'm running into crashes when using LSAN
standalone, therefore I'm using full ASAN instead (I'm not particularly
concerned about this: LSAN standalone mode is known to be less-well tested
than leak-checking within ASAN [1], and the crashes are occurring within the
leak-checker itself):

make GIT_TEST_OPTS="-i -v" DEFAULT_TEST_TARGET="t0000-basic.sh"
ASAN_OPTIONS="detect_leaks=1:abort_on_error=1" SANITIZE=address DEVELOPER=1
CFLAGS="-DSUPPRESS_ANNOTATED_LEAKS -g -fno-optimize-sibling-calls -O1
-fno-omit-frame-pointer" test

(I then rerun the entire test suite with ASAN but with leak-checking
disabled in order to gain some confidence that my fixes aren't inadvertently
introducing memory safety issues.)

[1]
https://github.com/google/sanitizers/wiki/AddressSanitizerLeakSanitizer#stand-alone-mode

Andrzej Hunt (7):
  symbolic-ref: don't leak shortened refname in check_symref()
  reset: free instead of leaking unneeded ref
  clone: free or UNLEAK further pointers when finished
  worktree: fix leak in dwim_branch()
  init: remove git_init_db_config() while fixing leaks
  init-db: silence template_dir leak when converting to absolute path
  parse-options: don't leak alias help messages

 builtin/clone.c        | 13 ++++++++++---
 builtin/init-db.c      | 32 ++++++++++----------------------
 builtin/reset.c        |  2 +-
 builtin/symbolic-ref.c | 12 +++++++++---
 builtin/worktree.c     | 12 ++++++------
 parse-options.c        | 29 ++++++++++++++++++++++++-----
 6 files changed, 60 insertions(+), 40 deletions(-)

base-commit: be7935ed8bff19f481b033d0d242c5d5f239ed50
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-899%2Fahunt%2Fleaksan-t0001-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-899/ahunt/leaksan-t0001-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/899
-- 
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