Comment 11 for bug 247669

Description of problem:

I have the vnc module enabled in my xorg.conf. If I use VNC from the beginning
of an X session, everything works fine. If I use X on the console for a while
and then connect to that same session via VNC, the session crashes...

Version-Release number of selected component (if applicable):

vnc-server-4.1.2-9.el5
xorg-x11-server-Xorg-1.1.1-48.13.0.1.el5

How reproducible:
Close to 100%. I have been doing this on 3 machines - a work machine with RHEL5
and two home machines with CentOS 5 and see this on all 3 (even though xorg.conf
are all somewhat different).

Steps to Reproduce:
1. Include the vnc module in xorg.conf
2. Restart X and use in on the console for a while
3. Make sure the right VNC parameters are enabled to allow VNC logins (use
vncconfig, if necessary)
4. Open a VNC connection to the X session.

Actual results:
X.org crashes. Here is the crash report in Xorg.0.log on the RHEL5 machine with
all updates:

Backtrace:
0: /usr/bin/Xorg(xf86SigHandler+0x81) [0x80bc1b1]
1: [0x302420]
2: /lib/libc.so.6(memcpy+0x1c) [0x4af9ca6c]
3: /usr/lib/xorg/modules/libfb.so(fbBlt+0x90e) [0x3fb39e]
4: /usr/lib/xorg/modules/libfb.so(fbBltStip+0x73) [0x3fb8c3]
5: /usr/lib/xorg/modules/libfb.so(fbGetImage+0x23a) [0x40b11a]
6: /usr/lib/xorg/modules/libxaa.so [0x1be2a2]
7: /usr/bin/Xorg [0x81088e8]
8: /usr/bin/Xorg [0x815b2a3]
9: /usr/bin/Xorg [0x811d4fd]
10:
/usr/lib/xorg/modules/extensions/libvnc.so(_ZN14XserverDesktop10grabRegionERKN3rfb6RegionE+0x12a)
[0x291c9a]
11:
/usr/lib/xorg/modules/extensions/libvnc.so(_ZN3rfb11VNCServerST11checkUpdateEv+0x1b7)
[0x29d457]
12:
/usr/lib/xorg/modules/extensions/libvnc.so(_ZN3rfb16VNCSConnectionST22writeFramebufferUpdateEv+0x5c)
[0x2ac8ec]
13:
/usr/lib/xorg/modules/extensions/libvnc.so(_ZN3rfb16VNCSConnectionST24framebufferUpdateRequestERKNS_4RectEb+0xbf)
[0x2ad1ef]
14:
/usr/lib/xorg/modules/extensions/libvnc.so(_ZN3rfb10SMsgReader28readFramebufferUpdateRequestEv+0x14f)
[0x2b3bcf]
15:
/usr/lib/xorg/modules/extensions/libvnc.so(_ZN3rfb12SMsgReaderV37readMsgEv+0x14a)
[0x2a83da]
16:
/usr/lib/xorg/modules/extensions/libvnc.so(_ZN3rfb11SConnection10processMsgEv+0x14f)
[0x2a7d7f]
17:
/usr/lib/xorg/modules/extensions/libvnc.so(_ZN3rfb16VNCSConnectionST15processMessagesEv+0x48)
[0x2abf18]
18:
/usr/lib/xorg/modules/extensions/libvnc.so(_ZN3rfb11VNCServerST18processSocketEventEPN7network6SocketE+0x3f)
[0x29d20f]
19:
/usr/lib/xorg/modules/extensions/libvnc.so(_ZN14XserverDesktop13wakeupHandlerEP6fd_seti+0xd4)
[0x291154]
20: /usr/lib/xorg/modules/extensions/libvnc.so [0x2893ec]
21: /usr/bin/Xorg(WakeupHandler+0x59) [0x808c169]
22: /usr/bin/Xorg(WaitForSomething+0x1b9) [0x81a0849]
23: /usr/bin/Xorg(Dispatch+0x8d) [0x8087f9d]
24: /usr/bin/Xorg(main+0x485) [0x806fa35]
25: /lib/libc.so.6(__libc_start_main+0xdc) [0x4af44dec]
26: /usr/bin/Xorg(FontFileCompleteXLFD+0x1e9) [0x806ed71]

Fatal server error:
Caught signal 11. Server aborting

Expected results:
VNC session starts

Additional info:
My xorg.conf:

Section "ServerLayout"
   Identifier "Default Layout"
   Screen 0 "Screen0" 0 0
   InputDevice "Keyboard0" "CoreKeyboard"
EndSection

Section "InputDevice"
   Identifier "Keyboard0"
   Driver "kbd"
   Option "XkbModel" "pc105"
   Option "XkbLayout" "us"
EndSection

Section "Monitor"
   Identifier "Mitsubishi"
   ModeLine "1800x1350" 299.67 1800 1968 2168 2480 1350 1351 1354 1397
-hsync -vsync
   Option "DPMS" "true"
EndSection

Section "Device"
   Identifier "Videocard0"
   Driver "nv"
EndSection

Section "Screen"
   Identifier "Screen0"
   Device "Videocard0"
   Monitor "Mitsubishi"
   DefaultDepth 24
   SubSection "Display"
                Virtual 1800 1350
      Viewport 0 0
      Depth 24
   EndSubSection
EndSection

Section "Module"
   SubSection "vnc"
   # XXX: Do not know why, but these options do not get picked up
      Option "SecurityTypes" "VncAuth"
      Option "PasswordFile" "/root/.vnc/passwd"
      Option "Localhost" "true"
      Option "AlwaysShared" "true"
   EndSubSection
   Load "extmod"
   Load "dbe"
   Load "glx"
   Load "freetype"
   Load "type1"
   Load "record"
   Load "dri"
   Load "drm"
EndSection