I see the same thing on Ubuntu 16.04 / apport 2.20.1-0ubuntu2.14 - same apport command line (except a different PID number), same error number and everything.
Looks like 'is_same_ns' is blindly doing an os.readlink on a path that it assumes must exist (because it does no defensive check) but the path clearly is missing sometimes
I see the same thing on Ubuntu 16.04 / apport 2.20.1-0ubuntu2.14 - same apport command line (except a different PID number), same error number and everything.
Looks like 'is_same_ns' is blindly doing an os.readlink on a path that it assumes must exist (because it does no defensive check) but the path clearly is missing sometimes