Suspend, shutdown and hibernate also work. Shutting down a computer with users logged in is a careless thing to do, those user could loose their work. I remember that GDM didn't allow such action.
-- You received this bug notification because you are a member of Desktop Packages, which is subscribed to lightdm in Ubuntu. https://bugs.launchpad.net/bugs/1249781 Title: System reboots even if someone is logged in Status in “lightdm” package in Ubuntu: New Bug description: The system can be rebooted from login screen even if another user is logged in, this could cause that user to loose changes to open files or cause some other kind of damage. How to reproduce: 1) Log in to your account 2) Lock screen (CTR+ALT+L) 3) Move the mouse to show password prompt 4) Click "Switch User" - it takes you to lightdm login prompt 5) Click restart in the power menu (upper right corner) What should happen: lightdm would demand that all users log out before rebooting What happens: system reboots ProblemType: Bug DistroRelease: Ubuntu 13.10 Package: lightdm 1.8.4-0ubuntu1 ProcVersionSignature: Ubuntu 3.11.0-13.20-generic 3.11.6 Uname: Linux 3.11.0-13-generic x86_64 ApportVersion: 2.12.5-0ubuntu2.1 Architecture: amd64 Date: Sun Nov 10 15:10:58 2013 InstallationDate: Installed on 2013-05-17 (176 days ago) InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424) MarkForUpload: True SourcePackage: lightdm UpgradeStatus: Upgraded to saucy on 2013-10-26 (14 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1249781/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
