qemu -- buffer overflow vulnerability in virtio-serial message exchanges

Prasad J Pandit, Red Hat Product Security Team, reports:

Qemu emulator built with the virtio-serial vmchannel support is
vulnerable to a buffer overflow issue. It could occur while
exchanging virtio control messages between guest and the host.
A malicious guest could use this flaw to corrupt few bytes of Qemu
memory area, potentially crashing the Qemu process.