submodule--helper: fix a memory leak in "status"

The "status" sub-command was leaking the "struct strvec" it was
setting up for the reasons explained in f92dbdb (revisions API:
don't leak memory on argv elements that need free()-ing, 2022-08-02),
so let's use the "free_removed_argv_elements" option to
setup_revisions() to fix the leak.

Even if we did that, clobbering the "diff_files_args.nr" with the
return value of setup_revisions() would leave leaks in place, but we
can just stop clobbering it.

Ever since that code was added in a9f8a37 (submodule: port
submodule subcommand 'status' from shell to C, 2017-10-06) we've had
no reason to modify the "nr" member ("argc" at the time): The next use
of "diff_files_args" after this is the "strvec_clear()" at the end of
the function.

Signed-off-by: Ævar Arnfjörð Bjarmason <[email protected]>
Signed-off-by: Taylor Blau <[email protected]>

Author: avar

builtin/submodule--helper.c

@@ -616,6 +616,9 @@ static void status_submodule(const char *path, const struct object_id *ce_oid,
 	int diff_files_result;
 	struct strbuf buf = STRBUF_INIT;
 	const char *git_dir;
+	struct setup_revision_opt opt = {
+		.free_removed_argv_elements = 1,
+	};
 
 	if (!submodule_from_path(the_repository, null_oid(), path))
 		die(_("no submodule mapping found in .gitmodules for path '%s'"),
@@ -649,9 +652,7 @@ static void status_submodule(const char *path, const struct object_id *ce_oid,
 
 	repo_init_revisions(the_repository, &rev, NULL);
 	rev.abbrev = 0;
-	diff_files_args.nr = setup_revisions(diff_files_args.nr,
-					     diff_files_args.v,
-					     &rev, NULL);
+	setup_revisions(diff_files_args.nr, diff_files_args.v, &rev, &opt);
 	diff_files_result = run_diff_files(&rev, 0);
 
 	if (!diff_result_code(&rev.diffopt, diff_files_result)) {

t/t7422-submodule-output.sh

@@ -2,6 +2,7 @@
 
 test_description='submodule --cached, --quiet etc. output'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-t3100.sh