[PATCH] hash-object: fix a trivial leak in --path

[PATCH] hash-object: fix a trivial leak in --path

[Ævar Arnfjörð Bjarmason]

Fix a memory leak that happened when the --path option was
provided. This leak has been with us ever since the option was added
in 39702431500 (add --path option to git hash-object, 2008-08-03).

We can now mark "t1007-hash-object.sh" as passing when git is compiled
with SANITIZE=leak. It'll now run in the the
"GIT_TEST_PASSING_SANITIZE_LEAK=true" test mode (the "linux-leaks" CI
target).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 builtin/hash-object.c  | 9 +++++++--
 t/t1007-hash-object.sh | 1 +
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/builtin/hash-object.c b/builtin/hash-object.c
index c7b3ad74c60..db9b2535271 100644
--- a/builtin/hash-object.c
+++ b/builtin/hash-object.c
@@ -92,6 +92,7 @@ int cmd_hash_object(int argc, const char **argv, const char *prefix)
 	int nongit = 0;
 	unsigned flags = HASH_FORMAT_CHECK;
 	const char *vpath = NULL;
+	char *vpath_free = NULL;
 	const struct option hash_object_options[] = {
 		OPT_STRING('t', NULL, &type, N_("type"), N_("object type")),
 		OPT_BIT('w', NULL, &flags, N_("write the object into the object database"),
@@ -114,8 +115,10 @@ int cmd_hash_object(int argc, const char **argv, const char *prefix)
 	else
 		prefix = setup_git_directory_gently(&nongit);
 
-	if (vpath && prefix)
-		vpath = prefix_filename(prefix, vpath);
+	if (vpath && prefix) {
+		vpath_free = prefix_filename(prefix, vpath);
+		vpath = vpath_free;
+	}
 
 	git_config(git_default_config, NULL);
 
@@ -156,5 +159,7 @@ int cmd_hash_object(int argc, const char **argv, const char *prefix)
 	if (stdin_paths)
 		hash_stdin_paths(type, no_filters, flags, literally);
 
+	free(vpath_free);
+
 	return 0;
 }
diff --git a/t/t1007-hash-object.sh b/t/t1007-hash-object.sh
index 64b340f2272..ac5ad8c7402 100755
--- a/t/t1007-hash-object.sh
+++ b/t/t1007-hash-object.sh
@@ -2,6 +2,7 @@
 
 test_description="git hash-object"
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 echo_without_newline() {
-- 
2.35.1.945.g180f8b8dd92

Re: [PATCH] hash-object: fix a trivial leak in --path

[Junio C Hamano]

Ævar Arnfjörð Bjarmason  <avarab@gmail.com> writes:

> diff --git a/builtin/hash-object.c b/builtin/hash-object.c
> index c7b3ad74c60..db9b2535271 100644
> --- a/builtin/hash-object.c
> +++ b/builtin/hash-object.c
> @@ -92,6 +92,7 @@ int cmd_hash_object(int argc, const char **argv, const char *prefix)
>  	int nongit = 0;
>  	unsigned flags = HASH_FORMAT_CHECK;
>  	const char *vpath = NULL;
> +	char *vpath_free = NULL;
>  	const struct option hash_object_options[] = {
>  		OPT_STRING('t', NULL, &type, N_("type"), N_("object type")),
>  		OPT_BIT('w', NULL, &flags, N_("write the object into the object database"),
> @@ -114,8 +115,10 @@ int cmd_hash_object(int argc, const char **argv, const char *prefix)
>  	else
>  		prefix = setup_git_directory_gently(&nongit);
>  
> -	if (vpath && prefix)
> -		vpath = prefix_filename(prefix, vpath);
> +	if (vpath && prefix) {
> +		vpath_free = prefix_filename(prefix, vpath);
> +		vpath = vpath_free;
> +	}
>  
>  	git_config(git_default_config, NULL);
>  
> @@ -156,5 +159,7 @@ int cmd_hash_object(int argc, const char **argv, const char *prefix)
>  	if (stdin_paths)
>  		hash_stdin_paths(type, no_filters, flags, literally);
>  
> +	free(vpath_free);
> +

Heh.

This is not wrong per-se, but we are about to exit and clean-up, so
having leak-checker complain about this and having us spend brain
cycles to worry about it is a sad thing.

Will queue.  Thanks.


>  	return 0;
>  }
> diff --git a/t/t1007-hash-object.sh b/t/t1007-hash-object.sh
> index 64b340f2272..ac5ad8c7402 100755
> --- a/t/t1007-hash-object.sh
> +++ b/t/t1007-hash-object.sh
> @@ -2,6 +2,7 @@
>  
>  test_description="git hash-object"
>  
> +TEST_PASSES_SANITIZE_LEAK=true
>  . ./test-lib.sh
>  
>  echo_without_newline() {