When handling patches which aren't generated by a VCS (such as dpkg-source for instance) it looks like Phabricator gets tripped up, leading to us getting the following error message:
Unhandled Exception ("AphrontQueryException") #1048: Column 'filename' cannot be null
These sorts of patches often come from Linux distributions which usually base their patches off tarballs rather than actual VCS checkouts. The use case for being able to handle these patches is the contributors/packagers in question are trying to upstream fixes which they've had to come up with to support their particular environment.
Given these patches are a little non-standard though, gracefully not accepting them would also be fine (not sure what your goals are upstream regarding patch handling)
Below is a patch which is known to trigger this condition