Red Hat Bugzilla – Bug 996306
openvpn-2.3.1-3.el6.x86_64 client crashes with segfault when bridged
Last modified: 2017-05-11 19:58:48 EDT
Description of problem:
When running OpenVPN as a client and bridging the tap0 interface, the client crashes at what seems to be an increase in data transmitted over the bridge.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Set up OpenVPN as a client with a tap device (not tun) and bridge the tap device with some other device, let's say eth3.
2. Make sure that this VPN tunnel is also bridged at the server side so that traffic can be sent over it.
3. When much traffic is being sent (in our case it was two Microsoft Windows Server Domain Controllers synchronising), the OpenVPN client process crashes with a segfault without writing anything in the log about it.
The OpenVPN client crashes with a segfault.
The OpenVPN client keeps running and keeps forwarding traffic from and to the bridge.
I solved the problem by downgrading to openvpn-2.2.2-1.el6.x86_64. The version run on the server doesn't change the results. Since the OpenVPN client doesn't log anything on crash, I can't include any relevant logs.
Can you try obtaining a backtrace? You should be able to install openvpn-debuginfo, and then:
gdb /usr/sbin/openvpn --daemon --writepid /var/run/openvpn/%i.pid --cd /etc/openvpn/ --config %i.conf
replacing %i with the openvpn config name you use. If it crashes and is missing needed debuginfo it will give you a debuginfo-install command line to run, do that and try again. Then at the segfault, type bt all and copy and paste the output here.
Is this still an issue? We have recently released OpenVPN v2.4.2? This does remind a bit of a few different bugs we've already fixed, but it is too little details to really know for sure.
I'm closing this now, but feel free to re-open if this is still an issue.