diff --git a/src/userprog/process.c b/src/userprog/process.c
index 65223c1..5c0b356 100644
--- a/src/userprog/process.c
+++ b/src/userprog/process.c
@@ -149,9 +149,9 @@ start_process (void *proc_start_data)
       sema_up (&data->loaded);
       thread_exit ();
     }
-  thread_current ()->exec_file = exec_file;
   file_deny_write (exec_file);
   lock_release (&filesys_lock);
+  thread_current ()->exec_file = exec_file;
 
   data->success = load (data->file_name, &if_.eip, &if_.esp);