[PATCH v3 1/3] unpack-trees: don't leak memory in verify_clean_subdirectory()
- From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
- Date
- Oct 13, 2021, 13:23 UTC
- Message-ID
- <patch-v3-1.3-0ab1e74f50d-20211013T132223Z-avarab@gmail.com>
- In-Reply-To
- <cover-v3-0.3-00000000000-20211013T132223Z-avarab@gmail.com>
Fix two different but related memory leaks in verify_clean_subdirectory(). We leaked both the "pathbuf" if read_directory() returned non-zero, and we never cleaned up our own "struct dir_struct" either.
* "pathbuf": When the read_directory() call followed by the free(pathbuf) was added in c81935348be (Fix switching to a branch with D/F when current branch has file D., 2007-03-15) we didn't bother to free() before we called die().
But when this code was later libified in 203a2fe1170 (Allow callers of unpack_trees() to handle failure, 2008-02-07) we started to leak as we returned data to the caller. This fixes that memory leak, which can be observed under SANITIZE=leak with e.g. the "t1001-read-tree-m-2way.sh" test.
* "struct dir_struct": We've leaked the dir_struct ever since this code was added back in c81935348be.
When that commit was written there wasn't an equivalent of dir_clear(). Since it was added in 270be816049 (dir.c: provide clear_directory() for reclaiming dir_struct memory, 2013-01-06) we've omitted freeing the memory allocated here.
This memory leak could also be observed under SANITIZE=leak and the "t1001-read-tree-m-2way.sh" test.
This makes all the test in "t1001-read-tree-m-2way.sh" pass under "GIT_TEST_PASSING_SANITIZE_LEAK=true", we'd previously die in tests 25, 26 & 28.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> --- t/t1001-read-tree-m-2way.sh | 2 ++ unpack-trees.c | 3 ++- 2 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/t/t1001-read-tree-m-2way.sh b/t/t1001-read-tree-m-2way.sh index 1057a96b249..d1115528cb9 100755 --- a/t/t1001-read-tree-m-2way.sh +++ b/t/t1001-read-tree-m-2way.sh @@ -20,6 +20,8 @@ In the test, these paths are used: rezrov - in H, deleted in M yomin - not in H or M ' + +TEST_PASSES_SANITIZE_LEAK=true . ./test-lib.sh . "$TEST_DIRECTORY"/lib-read-tree.sh diff --git a/unpack-trees.c b/unpack-trees.c index a7e1712d236..89ca95ce90b 100644 --- a/unpack-trees.c +++ b/unpack-trees.c @@ -2156,9 +2156,10 @@ static int verify_clean_subdirectory(const struct cache_entry *ce, if (o->dir) d.exclude_per_dir = o->dir->exclude_per_dir; i = read_directory(&d, o->src_index, pathbuf, namelen+1, NULL); + dir_clear(&d); + free(pathbuf); if (i) return add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name); - free(pathbuf); return cnt; }
-- 2.33.0.1569.gd2dc77f7abf