Public bug reported: To reproduce on a fresh install of ubuntu mate 16.04 start lightdm-gtk- greeter-settings and authenticate to start editing lightdm settings. Please do not try to reproduce this on a production machine as it will involve locking yourself out of lightdm. In the settings for lightdm GTK+ greeter settings select a really large image from a digial camera or high resolution screenshot as your user image that is larger than your screen resolution hit save and then log out. You will be taken to a lightdm screen that has a user image so large you cannot login.
Description: Ubuntu Xenial Xerus (development branch) Release: 16.04 lightdm-gtk-greeter-settings: Installed: 1.2.0-0ubuntu1 Candidate: 1.2.0-0ubuntu1 Version table: *** 1.2.0-0ubuntu1 0 500 http://us.archive.ubuntu.com/ubuntu/ xenial/universe amd64 Packages 100 /var/lib/dpkg/status I would expect the greeter to check that it would not set such redicolous file sizes that block the user from logging in or at least provide a warning dialog that this could make you unable to login similar to things that cause data loss on a partition in ubuquity or gparted. As this prevents even loggin into guest session graphically. I did manage to get back in editing /etc/lightdm/lightdm-gtk-greeter.conf by hand with vim. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: lightdm-gtk-greeter-settings 1.2.0-0ubuntu1 ProcVersionSignature: Ubuntu 4.2.0-16.19-generic 4.2.3 Uname: Linux 4.2.0-16-generic x86_64 ApportVersion: 2.19.2-0ubuntu1 Architecture: amd64 CurrentDesktop: MATE Date: Tue Nov 3 22:51:13 2015 InstallationDate: Installed on 2015-11-03 (0 days ago) InstallationMedia: Ubuntu-MATE 16.04 LTS "Xenial Xerus" - Alpha amd64 (20151103) PackageArchitecture: all SourcePackage: lightdm-gtk-greeter-settings UpgradeStatus: No upgrade log present (probably fresh install) ** Affects: lightdm-gtk-greeter-settings (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug xenial -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1512963 Title: settings allow arbitarly large user pictures which makes the user lock themselves out at lightdm. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm-gtk-greeter-settings/+bug/1512963/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs