Bug 1058423

Summary: Xorg crashes after upgrade of tigervnc-server-module
Product: Red Hat Enterprise Linux 6 Reporter: Libor Miksik <lmiksik>
Component: tigervncAssignee: Tim Waugh <twaugh>
Status: CLOSED ERRATA QA Contact: qe-baseos-daemons
Severity: high Docs Contact:
Priority: high    
Version: 6.5CC: alanm, amahdal, ashishks, azelinka, jfenal, jsvarova, mdomonko, pm-eus, twaugh
Target Milestone: rcKeywords: Patch, Regression, ZStream
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: tigervnc-1.1.0-8.el6_5 Doc Type: Bug Fix
Doc Text:
When using TigerVNC as a loadable X module, initialisation of the GLX extension was not performed correctly. This could lead to the X server crashing. A fix from a later version of tigervnc has been backported, and the GLX extension is now initialised correctly.
Story Points: ---
Clone Of: Environment:
Last Closed: 2014-02-03 11:18:38 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 1044244    
Bug Blocks:    

Description Libor Miksik 2014-01-27 18:28:42 UTC
This bug has been copied from bug #1044244 and has been proposed
to be backported to 6.5 z-stream (EUS).

Comment 5 Alois Mahdal 2014-01-30 14:37:03 UTC
Reproducer used for Erratum 2014:16812:

~

 1. Install 2 RHEL7 machines (A and B) with basic desktop
    (I used Server editions + Desktop option in Anaconda)
    and at least one non-root user (Admin in my case)
 2. A: change LAYOUT in /etc/sysconfig/keyboard to "es"
 3. A: install tigervnc-server-module
 4. A: create the .conf files stated below (10-module.conf,
    30-screen.conf).
 5. A: restart gdm, e.g.: `init 3; sleep 5; init 5;`
 6. A: disable firewall (or set rule to allow incoming tcp5900)
 7. B: install tigervnc (viewer)
 8. B: switch default keyboard layout to Spanish
    (System > Preferences > Keyboard ...)
 9. B: connect to B using tigervnc
     > you should see GDM greeter in the VNC desktop
10. B: Close the tigervnc window
     > if X server crashes on A, you have reproduced the bug
       (check mail for abrt reports)

~

/etc/X11/xorg.conf.d/10-module.conf:

Section "Module"
	Load	"vnc"
EndSection

/etc/X11/xorg.conf.d/30-screen.conf:

Section "Screen"
    Identifier "Screen0"
    DefaultDepth 24
    Subsection "Display"
       Viewport 0 0
       Depth 24
       Modes "1024x768"
    EndSubsection
    Option "SecurityTypes" "None"
EndSection

~

Notes: 

*   To check the same with new packages, you only need to update on A
    and restart the GDM (init...).  Old vncviewer is not affected by this
    bug at all.

    In fact, you could possibly use any other viewer on any other desktop
    as long as you are able to reproduce the bug with the old server
    module.  (AFAIK even the orignal report does not state what exactly
    they used). OTOH, above combination is as close to "officially
    supported" as it gets.

*   Also, I was not able to get the VNC server module working on several
    Beaker machines, even one with real graphics card. So I finally
    tested this in local KVM instance.  If you know how to make it work
    in Beaker, please update the reproducer.

Comment 6 Alois Mahdal 2014-01-30 17:23:49 UTC
Minor fixes to the reproducer:

(In reply to Alois Mahdal from comment #5)
>  1. Install 2 RHEL7 machines (A and B)

I mean RHEL6.


>  2. A: change LAYOUT in /etc/sysconfig/keyboard to "es"
>  [...]
>  8. B: switch default keyboard layout to Spanish
>     (System > Preferences > Keyboard ...)

Please ignore these steps (c/p error).  Layouts are irrelevant here.

Comment 7 Alois Mahdal 2014-01-30 19:47:36 UTC
verified on x86_64 and i386

Comment 9 errata-xmlrpc 2014-02-03 11:18:38 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHBA-2014-0125.html