LightDM leaves zombie processess when switching users

[Alen]

After user switching via greeter lightdm leaves a zombie process. Does happen only if switching via "Switch user account..." option. Tested on xubuntu 12.04 64-bit (bare metal and clean virtualbox install), also on ubuntu 12.04 64-bit (unity-2D, clean virtualbox install).

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: lightdm 1.2.1-0ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-23.36-generic 3.2.14
Uname: Linux 3.2.0-23-generic x86_64
ApportVersion: 2.0.1-0ubuntu5
Architecture: amd64
Date: Wed May 2 23:05:14 2012
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425)
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: lightdm
UpgradeStatus: No upgrade log present (probably fresh install)

[Alen (cshadow)]

Attached logs from /var/log/lightdm and output of ps

[Alen (cshadow)]

Attached screenshot from system monitor

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Sylwester (ubuntulinux-org)]

I get get around 5-6 new zombies every day and last boot was 6 days ago. The household uses this Ubuntu box as primary computer and we have each our own user so the number of zombies goes up every day. I would not have noticed then if it wasn't for Ubuntu's' excellent motd: "=> There are 29 zombie processes."

So far non of the zombies have threatened anyone so I guess it's low importance :p

[Pekka Tiittanen (pekka-tiittanen)]

We have 3 users (usually 2), uptime is now 8 days and I have 53 zombie processes from lightdm.