AssertionError during `ubuntu-bug xorg`

[Karl-Philipp Richter]

Invoking `ubuntu-bug xorg` fails with AssertionError

    ERROR: hook /usr/share/apport/package-hooks/source_xorg.py crashed:
    Traceback (most recent call last):
      File "/usr/lib/python3/dist-packages/apport/report.py", line 197, in _run_hook
        symb['add_info'](report, ui)
      File "/usr/share/apport/package-hooks/source_xorg.py", line 677, in add_info
        attach_nvidia_info(report, ui)
      File "/usr/share/apport/package-hooks/source_xorg.py", line 521, in attach_nvidia_info
        attach_file(report, logfile)
      File "/usr/lib/python3/dist-packages/apport/hookutils.py", line 115, in attach_file
        report[key] = read_file(path, force_unicode=force_unicode)
      File "/usr/lib/python3/dist-packages/problem_report.py", line 563, in __setitem__
        assert k.replace('.', '').replace('-', '').replace('_', '').isalnum()
    AssertionError

which is bad feedback for the user. In case something is missing it should be added as a dependency to `apport` or an understandable error message should be provided or the error should be silently skipped.

ProblemType: Bug
DistroRelease: Ubuntu 14.10
Package: apport-gtk 2.14.7-0ubuntu8
Uname: Linux 3.17.7-031707-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia
ApportVersion: 2.14.7-0ubuntu8
Architecture: amd64
CurrentDesktop: Unity
Date: Wed Dec 31 03:54:16 2014
EcryptfsInUse: Yes
InstallationDate: Installed on 2014-12-28 (3 days ago)
InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
PackageArchitecture: all
SourcePackage: apport
UpgradeStatus: Upgraded to utopic on 2014-12-28 (2 days ago)

[Marcus Tomlinson (marcustomlinson)]

This release of Ubuntu is no longer receiving maintenance updates. If this is still an issue on a maintained version of Ubuntu please let us know.

[Launchpad Janitor (janitor)]

[Expired for apport (Ubuntu) because there has been no activity for 60 days.]