Subject: Segfault of _X11TransWritev in libNX_X11.so.6 with libQtGui
From: Sven Willenberger <[email-masked]>
To: [email-masked]
Date: Thu, 23 Jan 2014 21:39:19 -0500

Package: nx-libs (nx-x11)
Version: 3.5.0.22

Server (host)OS: Linux 3.12.8 (ArchLinux) x86_64
Client OS: Windows 8 (version 4.0.1.2 QT 4.8.5)

When using python apps with QT (either PyQT or PySide), any interaction
with the resulting window (when connected from windows to linux) causes
the program to crash. Partial stack trace:

#0  0x00007fffed78acb0 in _X11TransWritev () from /usr/lib/nx/X11/libNX_X11.so.6
#1  0x00007fffed76eb8e in _XSend () from /usr/lib/nx/X11/libNX_X11.so.6
#2  0x00007fffed763e69 in XQueryExtension () from /usr/lib/nx/X11/libNX_X11.so.6
#3  0x00007fffed759af2 in XInitExtension () from /usr/lib/nx/X11/libNX_X11.so.6
#4  0x00007fffeda3d7bb in XextAddDisplay () from /usr/lib/nx/X11/libNX_Xext.so.6
#5  0x00007fffedc4cee1 in XPanoramiXQueryExtension () from /usr/lib/nx/X11/Xinerama/libXinerama.so.1
#6  0x00007ffff0e01e3e in ?? () from /usr/lib/python3.3/site-packages/PySide-1.2.1-py3.3.egg/PySide/libQtGui.so.4
#7  0x00007ffff0e01f42 in QDesktopWidget::QDesktopWidget() () from /usr/lib/python3.3/site-packages/PySide-1.2.1-py3.3.egg/PySide/libQtGui.so.4

This just happened with the Jan 4 update to nx-libs (et al).

For comparison, using a basic ssh connection with X-forwarding and
starting an xterm session and running the same python programs succeeds.

-- 
Sven Willenberger
United Pay Systems International
http://www.upsicorp.com