Security Audit Request for Screenlocker Branch

Martin Gräßlin mgraesslin at
Tue Oct 11 15:00:17 BST 2011

On Tuesday 11 October 2011 16:06:11 Andras Mantia wrote:
> From here:
> "If KWin crashes without restarting privacy is leaked but the system is
> hardly useable due to missing window manager. This situation can savely
> be ignored as a corner case as KWin normaly restart."
> This is not true, the system can be used without a window manager and if
> you happen to have a running terminal or start one, it is possible to
> start a new window manager (which might not be kwin) and access
> everything.
yes if you have a terminal open and if it is the top most of stacking order it 
is possible to start another window manager. If that is not the case you are 
not able to start anything as KRunner or kickoff cannot be opened.

I think there is hardly anyone here on the list who is as experienced as I am 
with situations where you don't have a window manager running ;-) That part of 
the wiki page was written based on my own experience with the issues of 
restarting KWin when it failed badly during development.
> I had several times the case (for whatever reason) when I was without a
> running kwin and had to start one manually.
KWin has currently one reproducable crash listed in bko. This crash cannot be 
triggered when the screen is locked. If you have any crashes for KWin please 
report them. The most often triggerable crash due to driver faults will be 
fixed by the new screen locker implementation.

I myself have never run into a situation where KWin did not restart except for 
development issues (broken setup due to incompatible Oxygen client deco and 
Oxygen lib or PEBKAC during development).

I consider the remaining chances to get KWin to not restart as an extreme 
corner case. Obviously we will consider each new crash report as a possible 
security issue and will evaluate the danger coming from it. But in general 
KWin is a very crash resistant application nowadays. All crashers we have come 
from drivers and that should not be an issue during the screen is locked (no 
ares involved which might trigger the well-known crashes).

> Andras
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: This is a digitally signed message part.
URL: <>

More information about the kde-core-devel mailing list