Fix CVE-2014-3153

futex-prevent-requeue-pi-on-same-futex.patch futex:
Forbid uaddr == uaddr2 in futex_requeue(..., requeue_pi=1)

If uaddr == uaddr2, then we have broken the rule of only requeueing from
a non-pi futex to a pi futex with this call.  If we attempt this, then
dangling pointers may be left for rt_waiter resulting in an exploitable
condition.

This change brings futex_requeue() in line with futex_wait_requeue_pi()
which performs the same check as per commit 6f7b0a2a5c0f ("futex: Forbid
uaddr == uaddr2 in futex_wait_requeue_pi()")

[ tglx: Compare the resulting keys as well, as uaddrs might be
  	different depending on the mapping ]

Change-Id: Ibe6195215657c86bf2e39305656fdacf7230389d
Reported-by: Pinkie Pie
Signed-off-by: Will Drewry <wad@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'linux-3.0.y' of 'linux' into cm-11.0

Conflicts:
	crypto/algapi.c
	drivers/gpu/drm/i915/i915_debugfs.c
	drivers/gpu/drm/i915/intel_display.c
	drivers/video/fbmem.c
	include/linux/nls.h
	kernel/cgroup.c
	kernel/signal.c
Fix merge
Touchwake
Boeffla sound