*** This bug is a security vulnerability ***
You have been subscribed to a public security bug:
Sometimes when the screen is locked and I press a key to unlock it, I
see my entire desktop and open windows under the password dialog box.
That's a security problem.
I believe this is a compositing / video memory issue, because of the
following factors:
1.) It is intermittent, but occurs most when the screen is "busy" (lots of
graphics-heavy windows open).
2.) I can almost always reproduce it by doing something video-intensive,
such as x11perf.
3.) Sometimes everything will be visible except that one or two windows,
or the "active" portions thereof, will be blacked out.
4.) I have seen other compositing / video memory glitches, such as the
contents of a previously closed window appearing briefly in a newly
opened window before it completes drawing (another security issue in its
own right).
5.) The desktop is shown as it appeared when the screen was locked, and
does not update while locked.
6.) I am unable to reproduce the issue with compositing ("desktop
effects") disabled.
Note that the desktop is not dimmed; it is visible for as long as you want to
stare at it, even after the password prompt has disappeared; and I am using
dualhead and both screens are visible, so this is not a duplicate of #390989 or
#385102 or #417722, though it is probably related. I have attached two
screenshots (acquired via VNC) demonstrating the problem.
I'm running Kubuntu 9.04 x86-64 with all updates, using the NVidia
180.44 binary driver with TwinView on a GeForce 8400 GS.
** Affects: kdebase-workspace (Ubuntu)
Importance: Undecided
Status: Incomplete
** Tags: compositing desktop dualhead kubuntu kwin lock nvidia screen twinview
visible
--
Desktop visible when screen is locked in Kubuntu
https://bugs.launchpad.net/bugs/474654
You received this bug notification because you are a member of Kubuntu Bugs,
which is subscribed to kdebase-workspace in ubuntu.
--
kubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/kubuntu-bugs
