CVE-2017-17381 Qemu: virtio: divide by zero exception while updating rings

[P J P <ppandit () redhat com>]

  Hello,

Virtio Vring implementation in Quick Emulator(QEMU) is vulnerable to an 
arithmetic exception issue. It could occur if a guest was to unset vring 
alignment while updating Virtio rings.

A guest user/process could use this flaw to crash Qemu process resulting in 
DoS.

Upstream patch:
---------------
  -> https://lists.gnu.org/archive/html/qemu-devel/2017-12/msg00166.html

This issue was reported by Huawei Alpha Labs.

'CVE-2017-17381' assigned via -> https://cveform.mitre.org/

Thank you.
--
Prasad J Pandit / Red Hat Product Security Team
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