CVE request Qemu: usb: multiple eof_timers in ohci leads to null pointer dereference

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

  Hello,

Qemu emulator built with the USB OHCI emulation support is vulnerable to a 
null pointer dereference issue. It could occur when OHCI transitions to a 
OHCI_USB_OPERATIONAL state, leading to creation of multiple eof timers. A 
privileged user inside guest could use this flaw to crash the Qemu process on 
the host, resulting in DoS.

Upstream patch:
---------------
  -> https://lists.gnu.org/archive/html/qemu-devel/2016-02/msg03374.html

Reference:
----------
  -> https://bugzilla.redhat.com/show_bug.cgi?id=1304794

This issue was discovered by Zuozhi Fzz of Alibaba Inc.

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