kernel: Fix task flag marking for root and shell UID

Signed-off-by: Wang Han <416810799@qq.com>
Co-authored-by: 5ec1cff <56485584+5ec1cff@users.noreply.github.com>

kernel/kernel_umount.c

@@ -133,6 +133,11 @@ int ksu_handle_umount(uid_t old_uid, uid_t new_uid)
         return 0;
     }
 
+    // FIXME: isolated process which directly forks from zygote is not handled
+    if (!is_appuid(new_uid)) {
+        return 0;
+    }
+
     if (!ksu_uid_should_umount(new_uid)) {
         return 0;
     }