Merge branch 'netback'

Ian Campbell says:

====================
The Xen netback implementation contains a couple of flaws which can
allow a guest to cause a DoS in the backend domain, potentially
affecting other domains in the system.

CVE-2013-0216 is a failure to sanity check the ring producer/consumer
pointers which can allow a guest to cause netback to loop for an
extended period preventing other work from occurring.

CVE-2013-0217 is a memory leak on an error path which is guest
triggerable.

The following series contains the fixes for these issues, as previously
included in Xen Security Advisory 39:
http://lists.xen.org/archives/html/xen-announce/2013-02/msg00001.html

Changes in v2:
 - Typo and block comment format fixes
 - Added stable Cc
====================

Signed-off-by: David S. Miller <davem@davemloft.net>