Red Hat Bugzilla – Bug 802644
segfault when attempting to detach non-existent network device
Last modified: 2012-06-20 02:50:03 EDT
The patches for Bug 691539 introduced a regression in network device detach. A fix has been pushed upstream, and needs to be backported to RHEL: commit 19c7980ee6ca94308313b440fd39f308b4ae844e Author: Guannan Ren <gren@redhat.com> Date: Mon Mar 12 23:50:02 2012 +0800 qemu: fix segfault when detaching non-existent network device In qemuDomainDetachNetDevice, detach was being used before it had been validated. If no matching device was found, this resulted in a dereference of a NULL pointer. This behavior was a regression introduced in commit cf90342be0022520e25cfa258cef1034b229a100, so it has not been a part of any official libvirt release.
A backported fix has been posted to rhvirt-patches for inclusion in the RHEL build of libvirt: http://post-office.corp.redhat.com/archives/rhvirt-patches/2012-March/msg01463.html
Use libvirt-0.9.10-4.el6.x86_64 to reproduce the bug. #virsh detach-device rhel6 net.xml error: Failed to detach device from net.xml error: End of file while reading data:Input/Output error Verify steps 1.# rpm -q libvirt libvirt-0.9.10-6.el6.x86_64 2.Prepare the following xml. <interface type='user'> <mac address='02:11:22:33:44:55'/> <model type='virtio'/> </interface> 3.# virsh attach-device rhel6 net.xml Device attached successfully 4.# virsh detach-device rhel6 net.xml Device detached successfully 5.# virsh detach-device rhel6 net.xml error: Failed to detach device from /home/net.xml error: operation failed: network device 02:11:22:33:44:55 not found So it is verified.
Technical note added. If any revisions are required, please edit the "Technical Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. New Contents: (This bug was never in a released version of libvirt, so no thecnical note is required)
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/RHSA-2012-0748.html