Red Hat Bugzilla – Bug 1456424
qemu crash when starting image streaming job fails
Last modified: 2017-08-02 00:41:00 EDT
If block_job_create() fails for image streaming, qemu crashes with a segfault (NULL pointer access). This can be reproduced by using the QMP block-stream command, specifying a node name as 'device' and not providing a job ID. The problem is fixed upstream with the patch "stream: fix crash in stream_start() when block_job_create() fails", which is not in git master yet. Reproducer: $ qemu-img create -f qcow2 /tmp/base.qcow2 64M $ qemu-img create -f qcow2 -b /tmp/base.qcow2 /tmp/sn1.qcow2 $ qemu-img create -f qcow2 -b /tmp/sn1.qcow2 /tmp/sn2.qcow2 $ qemu-system-x86_64 -drive file=/tmp/sn2.qcow2,backing.node-name=mid -qmp stdio {"QMP": {"version": {"qemu": {"micro": 0, "minor": 9, "major": 2}, "package": "(v2.9.0-119-gd3498bc)"}, "capabilities": []}} {"execute":"qmp_capabilities"} {"return": {}} {"execute":"block-stream","arguments":{"device":"mid"}} Segmentation fault (core dumped) Expected result: {"error": {"class": "GenericError", "desc": "An explicit job ID is required for this node"}}
QE has reproduced this issue on qemu-kvm-rhev-2.9.0-7.el7.x86_64, follow the steps listed in comment 0. Replace 'backing.node-name=mid' with 'node-name=mid' or 'id=mid' won't trigger core dump.
Fix included in qemu-kvm-rhev-2.9.0-8.el7
Verified on qemu-kvm-rhev-2.9.0-9.el7.x86_64 following steps from comment 0, Result: qmp prompt error preventing the block job: {"error": {"class": "GenericError", "desc": "An explicit job ID is required for this node"}}
Moving to VERIFIED per comment 4 and comment 5.
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://access.redhat.com/errata/RHSA-2017:2392