diff --git a/app/controllers/active_storage/disk_controller_decorator.rb b/app/controllers/active_storage/disk_controller_decorator.rb
index 0364efa9..295913bc 100644
--- a/app/controllers/active_storage/disk_controller_decorator.rb
+++ b/app/controllers/active_storage/disk_controller_decorator.rb
@@ -58,7 +58,7 @@ module ActiveStorage
 
       def limits(max_upload_size, max_download_size)
         ruby_hash = { max_upload_size: max_upload_size, max_download_size: max_download_size }
-        json_string = JSON.generate(ruby_hash)
+        JSON.generate(ruby_hash)
       end
 
       private