VirtualBox 4.1.18 crashes. Segfault in libQtCore.so.4.8.1

[Mikko Valkonen]

I have been successfully using the newest Oracle Virtualbox for Ubuntu 12.04 amd64 for quite a while now. Apparently libqtcore4 was upgraded a while ago and now I cannot start virtualbox anymore. The window pops up and closes after a couple of seconds. Nothing seems to help. I believe I've tracked the issue down to a piece of code in the libQtCore.so.4.8.1. Could not find a bug report on this, sorry if it's a double. I'll provide more information if necessary.

msvalkon@Lunkwill:~/work/gecko/tools$ virtualbox
Error opening file for reading: Permission denied <-- Which file could this be?
Segmentation fault

Dmesg:
[ 6160.368735] VirtualBox[6144]: segfault at 29 ip 00007fd397f4824c sp 00007fff70efc3a8 error 4 in libQtCore.so.4.8.1[7fd397e86000+2c6000]

Running gdb produces the following output:
msvalkon@Lunkwill:~/work/gecko/tools$ sudo gdb /usr/lib/virtualbox/VirtualBox
GNU gdb (Ubuntu/Linaro 7.4-2012.04-0ubuntu2) 7.4-2012.04
Copyright (C) 2012 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
For bug reporting instructions, please see:
<http://bugs.launchpad.net/gdb-linaro/>...
Reading symbols from /usr/lib/virtualbox/VirtualBox...(no debugging symbols found)...done.
(gdb) file /usr/lib/virtualbox/VirtualBox
Reading symbols from /usr/lib/virtualbox/VirtualBox...(no debugging symbols found)...done.
(gdb) start
Function "main" not defined.
Make breakpoint pending on future shared library load? (y or [n]) y
Temporary breakpoint 1 (main) pending.
Starting program: /usr/lib/virtualbox/VirtualBox
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7f2f564be700 (LWP 5958)]
[New Thread 0x7f2f5649d700 (LWP 5959)]
[Thread 0x7f2f5649d700 (LWP 5959) exited]
[Thread 0x7f2f564be700 (LWP 5958) exited]
[New Thread 0x7f2f564be700 (LWP 5964)]
[New Thread 0x7f2f5649d700 (LWP 5965)]
[New Thread 0x7f2f3d9ed700 (LWP 5984)]
[Thread 0x7f2f3d9ed700 (LWP 5984) exited]
[New Thread 0x7f2f3d9ed700 (LWP 5990)]
[New Thread 0x7f2f37fff700 (LWP 6000)]
[New Thread 0x7f2f373c3700 (LWP 6001)]
[New Thread 0x7f2f36bc2700 (LWP 6002)]

Program received signal SIGSEGV, Segmentation fault.
0x00007f2f4da5424c in QString::indexOf(QChar, int, Qt::CaseSensitivity) const () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4

Package information:
msvalkon@Lunkwill:~/work/gecko/tools$ apt-cache policy libqtcore4
libqtcore4:
  Installed: 4:4.8.1-0ubuntu4.1
  Candidate: 4:4.8.1-0ubuntu4.1
  Version table:
 *** 4:4.8.1-0ubuntu4.1 0
        500 http://fi.archive.ubuntu.com/ubuntu/ precise-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     4:4.8.1-0ubuntu4 0
        500 http://fi.archive.ubuntu.com/ubuntu/ precise/main amd64 Packages

msvalkon@Lunkwill:/usr/lib/virtualbox$ lsb_release -rd
Description: Ubuntu 12.04 LTS
Release: 12.04

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: libqtcore4 4:4.8.1-0ubuntu4.1
ProcVersionSignature: Ubuntu 3.2.0-25.40-generic 3.2.18
Uname: Linux 3.2.0-25-generic x86_64
ApportVersion: 2.0.1-0ubuntu8
Architecture: amd64
Date: Thu Jun 28 11:08:27 2012
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Beta amd64 (20120328)
ProcEnviron:
 LANGUAGE=en_US:en
 TERM=xterm
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: qt4-x11
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Jordi Miguel (neoclimber)]

Affects also to Ubuntu Lucid Lynx 10.04 with:

libqtcore4:
  Installed: 4:4.6.2-0ubuntu5.4
  Candidate: 4:4.6.2-0ubuntu5.4

[Mikko Valkonen (msvalkon)]

To spice things up a little, I might add that this also affects me with the most recent ubuntu release 12.10.

libqtcore4:
  Installed: 4:4.8.3+dfsg-0ubuntu3
  Candidate: 4:4.8.3+dfsg-0ubuntu3