title: Asp.net Core RequestSizeLimit still executes action
body: <p>I am using ASP.net Core 2.0 with MVC. I have a controller action that I want to limit the request size to 1MB. I added the <code>RequestSizeLimit</code> attribute like so:</p>
  
  <pre><code>[HttpPost]
  [Authorize]
  [RequestSizeLimit(1_000_000)]
  public async Task&lt;List&lt;ResourceUploadResult&gt;&gt; Upload([FromBody]List&lt;Resource&gt; updatedList){
      //....
  }
  </code></pre>
  
  <p>When the upload is &lt; 1MB, it works as expected. When it is > 1MB I expected the server to return a status of 413, but instead, the <code>updatedList</code> parameter is null and the action executes normally, running into a <code>NullReferenceException</code> when it tries to iterate the list.</p>
  
  <p>Is there a way to tell Kestrel to return 413 when the size limit is reached?</p>