[CVE-2011-1747] agp: fix OOM and buffer overflow

[Andy Whitcroft]

CVE-2011-1747
	The agp subsystem in the Linux kernel 2.6.38.5 and earlier does not
	properly restrict memory allocation by the (1) AGPIOC_RESERVE and
	(2) AGPIOC_ALLOCATE ioctls, which allows local users to cause a
	denial of service (memory consumption) by making many calls to
	these ioctls.

The fix for this issue is already applied for Oneiric, Natty, and Lucid
arriving via mainline/stable updates.  Following this email is a patch
which applies to both Maverick and Hardy correcting the flaw.

Proposing for Hardy and Maverick.

-apw