CVE-2017-12809 Qemu: ide: flushing of empty CDROM drives leads to NULL dereference

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

  Hello,

Quick emulator built with the IDE disk and CD/DVD-ROM Emulator support is 
vulnerable to a null pointer dereference issue. It could occur while flushing 
an empty CDROM device drive.

A privileged user inside guest could use this flaw to crash the Qemu process 
resulting in DoS.

Upstream patch:
---------------
  -> https://lists.gnu.org/archive/html/qemu-devel/2017-08/msg01850.html

'CVE-2017-12809' assigned via -> https://cveform.mitre.org/

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