gltext seems to leak memory eventually causing oom-killer to run

I guess you are using the nvidia proprietary driver? Does this happen if you use the open-source nouveau driver (you may need to install the libgl1-mesa-dri-experimental from universe)?

I will try that as soon as I am back at that computer. I did want to point out that someone on Gentoo had a similar problem problem and there is a link to a patch. I am not sure if it is the same issue but it looks pretty similar http://bugs.gentoo.org/351173

ok I switched to the nouveau driver and the exact same thing happened. I watched the memory usage in top and it just keeps rising pretty dramatically until oom-killer is invoked and kills it.

Thanks. The patch was included in upstream version 5.13.

This bug was fixed in the package xscreensaver - 5.13-1ubuntu1

---------------
xscreensaver (5.13-1ubuntu1) oneiric; urgency=low

  * Merge with Debian unstable, remaining Ubuntu changes:
  * debian/control:
    - Build-Depend on ubuntu-artwork
    - Add Vcs-Bzr link
    - Move xli | xloadimage xscreensaver recommends to suggests
    - Add/Update replaces with Ubuntu versions
    - Update package descriptions to list Ubuntu screensavers
  * debian/rules:
    - Use /usr/share/backgrounds as image directory
    - Add translation domain to .desktop files
  * debian/source_xscreensaver.py:
    - Add apport hook
  * debian/split-hacks.config:
    - Use different set of default hacks than Debian
  * debian/xscreensaver.dirs
    - Install /usr/share/backgrounds. By default, settings search in
      /usr/share/backgrounds and without it, it displays an error
  * debian/patches/53_XScreenSaver.ad.in.patch:
    - Use Ubuntu branding

xscreensaver (5.13-1) unstable; urgency=low

  * New upstream version 5.13
    - Passwords that contain UTF-8 non-Latin1 chars are now typeable
    - pt_BR translation (thanks Sérgio Cipolla!) (Closes: #586230)
    - Fix memory leak in gltext (LP: #768032)
  * Build without gdm and libgnome2-dev (Closes: #618165)
  * Add Suggests on gdm3 or kdm-gdmcompat because gdmflexiserver
    can be used for the "New Login" functionality (see bug #304406)
  * Remove obsolete gdmflexiserver options
  * xscreensaver.desktop changes:
    - Do not set StartupNotify.
    - Do not specify svg icon. Closes: #618723 (LP: #603222)
  * Fix installation path for xscreensaver-daemon.desktop
  * debian/xscreensaver.preinst: Check version before
    deleting obsolete configuration files (Closes: #588288)
  * Bump Standards-Version to 3.9.1 (no changes needed)
 -- Jeremy Bicha <email address hidden> Wed, 18 May 2011 15:39:48 +0200

It looks like this was supposed to be fixed in natty as well, but 5.12-0ubuntu4 did not make it to the archives: http://bazaar.launchpad.net/~ubuntu-desktop/xscreensaver/ubuntu/revision/25
http://bazaar.launchpad.net/~ubuntu-desktop/xscreensaver/ubuntu/revision/26

It crashes my computer in Natty. This is a serious bug, because it causes all kinds of havoc. Loss of data, for one thing.

However, this is not just a bug in gltext: it is a bug in xscreensaver. Xscreensaver should adjust the OOM killer to preferentially kill its subprocesses. A screensaver subprocess is *NOT* an important process -- it should not be allowed to run wild and endanger the operation of the rest of the system.

A simple manipulation in /proc/[pid]/oom_adj would solve the problem.

open("/proc/%d/oom_adj", "w").write("10\n")

would do the trick.

This leak occurs even when using the 'preview' dialog, see attachment.

Robert Ancell fixed this in the bazaar branch and prepared a natty package release. I assume he forgot to actually upload it?