selftests/bpf: Fix memory leak in test selector

Free test selector substrings, which were strdup()'ed.

Fixes: b65053cd ("selftests/bpf: Add whitelist/blacklist of test names to test_progs")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200429012111.277390-6-andriin@fb.com

tools/testing/selftests/bpf/test_progs.c

@@ -420,6 +420,18 @@ static int libbpf_print_fn(enum libbpf_print_level level,
 	return 0;
 }
 
+static void free_str_set(const struct str_set *set)
+{
+	int i;
+
+	if (!set)
+		return;
+
+	for (i = 0; i < set->cnt; i++)
+		free((void *)set->strs[i]);
+	free(set->strs);
+}
+
 static int parse_str_list(const char *s, struct str_set *set)
 {
 	char *input, *state = NULL, *next, **tmp, **strs = NULL;
@@ -756,11 +768,11 @@ int main(int argc, char **argv)
 	fprintf(stdout, "Summary: %d/%d PASSED, %d SKIPPED, %d FAILED\n",
 		env.succ_cnt, env.sub_succ_cnt, env.skip_cnt, env.fail_cnt);
 
-	free(env.test_selector.blacklist.strs);
-	free(env.test_selector.whitelist.strs);
+	free_str_set(&env.test_selector.blacklist);
+	free_str_set(&env.test_selector.whitelist);
 	free(env.test_selector.num_set);
-	free(env.subtest_selector.blacklist.strs);
-	free(env.subtest_selector.whitelist.strs);
+	free_str_set(&env.subtest_selector.blacklist);
+	free_str_set(&env.subtest_selector.whitelist);
 	free(env.subtest_selector.num_set);
 
 	return env.fail_cnt ? EXIT_FAILURE : EXIT_SUCCESS;