selftests/landlock: Fix a resource leak

The opened file should be closed before return, otherwise resource leak
will occur.

Signed-off-by: Ding Xiang <dingxiang@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20230830101148.3738-1-dingxiang@cmss.chinamobile.com
Fixes: 3de64b656b3c ("selftests/landlock: Add supports_filesystem() helper")
Signed-off-by: Mickaël Salaün <mic@digikod.net>

diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c
index 83d5655..2515943 100644 (file)
--- a/tools/testing/selftests/landlock/fs_test.c
+++ b/tools/testing/selftests/landlock/fs_test.c
@@ -113,7 +113,7 @@ static bool supports_filesystem(const char *const filesystem)
 {
        char str[32];
        int len;
-       bool res;
+       bool res = true;
        FILE *const inf = fopen("/proc/filesystems", "r");
 
        /*
@@ -125,14 +125,16 @@ static bool supports_filesystem(const char *const filesystem)
 
        /* filesystem can be null for bind mounts. */
        if (!filesystem)
-               return true;
+               goto out;
 
        len = snprintf(str, sizeof(str), "nodev\t%s\n", filesystem);
        if (len >= sizeof(str))
                /* Ignores too-long filesystem names. */
-               return true;
+               goto out;
 
        res = fgrep(inf, str);
+
+out:
        fclose(inf);
        return res;
 }