RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Created attachment 938829 [details]
libvird coredump log file.

description of problem:
libvirtd crashed after running "virsh metadata --remove" command.

version:
libvirt-1.2.8-2.el7.x86_64
qemu-kvm-1.5.3-60.el7.x86_64

How reproducible:
100%

step to reproduce:
1. There is no metadata in guest xml.
# virsh list --all
 Id    Name                           State
----------------------------------------------------
 -     virt-tests-vm1                 shut off
# virsh dumpxml virt-tests-vm1 | grep metadata
# ps aux | grep libvirtd
root     11804  0.2  0.2 472144 21924 ?        Ssl  17:44   0:00 /usr/sbin/libvirtd
root     11860  0.0  0.0 112640  1024 pts/0    S+   17:44   0:00 grep --color=auto libvirtd

2. run "virsh metadata" command, libvird crashed.
# virsh metadata virt-tests-vm1 "http://herp.derp/" --remove
error: End of file while reading data: Input/output error
error: Failed to reconnect to the hypervisor
# ps aux | grep libvirtdroot     11863  3.0  0.2 472144 17832 ?        Ssl  17:44   0:00 /usr/sbin/libvirtd
root     11919  0.0  0.0 112640  1024 pts/0    S+   17:44   0:00 grep --color=auto libvirtd

3. Attached libvirtd coredump log file.

Actual results:
As described.

Expect result:
libvirtd shouldn't crash.

Fixed upstream:

commit 288c47406cffa7a6eb9e9c29764850b0cdeb5508
Author: Erik Skultety <eskultet>
Date:   Thu Sep 18 14:25:05 2014 +0200

    Fix libvirtd crash when removing metadata
    
    When trying to remove nonexistent metadata from XML, libvirt daemon
    crashes due to dereferencing NULL pointer.
    
    Resolves https://bugzilla.redhat.com/show_bug.cgi?id=1143955

v1.2.8-197-g288c474

I can reproduct this issue with build: libvirt-1.2.8-2.el7.x86_64

verify with build:libvirt-1.2.8-4.el7.x86_64

step:
# ps -ef | grep libvirtd
root     15093     1  1 13:52 ?        00:00:00 /usr/sbin/libvirtd
root     15119 14076  0 13:53 pts/0    00:00:00 grep --color=auto libvirtd

# virsh metadata rhel7 "http://herp.derp" --remove
Metadata removed

# ps -ef | grep libvirtd
root     15093     1  1 13:52 ?        00:00:00 /usr/sbin/libvirtd

libvirtd not crash
movet to verified.

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.

https://rhn.redhat.com/errata/RHSA-2015-0323.html