[Pkg-xfce-devel] Bug#732854: lightdm shows a part of my desktop screen as a part of the background of the login screen

[Yves-Alexis Perez]

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On Sun, Dec 22, 2013 at 04:54:12PM +0100, Vincent Lefevre wrote:
> Package: lightdm
> Version: 1.8.5-2
> Severity: grave
> Tags: security
> Justification: user security hole
> 
> Here's what I did:
> 1. Quit me desktop session.
> 2. In lightdm (whose screen appeared correctly), clicked on "Restart".
> 3. Waited for the restart, chose the default Linux kernel...
> 
> First lightdm seemed to be confused by the screen resolution because
> the display of the login box didn't appear at the right place first.
> Note that the machine is a laptop, and I use it at home with a larger
> external screen, but since yesterday morning I'm no longer at home.
> I wonder whether this is related (but note that in step 2, everything
> was OK).
> 
> Then the login box reappeared correctly. However the background was
> still incorrect, with parts of my desktop screen, i.e. private data
> accessible to everyone! There was nothing really private here, but
> there could have been a password visible or other private information
> or whatever.
> 
> I'm attaching a photo I took of the laptop screen.

Looks like your graphics driver (most likely nvidia/nouveau) doesn't
clean the video memory. Definitely not a lightdm issue.

Regards,
- -- 
Yves-Alexis Perez
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