qemu -- denial of service vulnerability in Q35 chipset emulation

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

Qemu emulator built with the Q35 chipset based pc system emulator
is vulnerable to a heap based buffer overflow. It occurs during VM
guest migration, as more(16 bytes) data is moved into allocated
(8 bytes) memory area.
A privileged guest user could use this issue to corrupt the VM
guest image, potentially leading to a DoS. This issue affects q35
machine types.