Right! It turns out that my lo interface _was_ the culprit after all. It seems GDM wanted to use ipv6, which my firewall script blindly dropped. Now that I have changed it to accept ipv6 packets to/from the lo interface, all is well again!
** Changed in: gnome-session (Ubuntu) Status: Unconfirmed => Rejected ** Changed in: gdm (upstream) Importance: Unknown => Undecided Bugwatch: GNOME Bug Tracker #432624 => None Status: Unknown => Unconfirmed -- Couldn't open any new programs or log out https://bugs.launchpad.net/bugs/108761 You received this bug notification because you are a member of Ubuntu Bugs, which is the bug contact for Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs