ARM: allow kuser helpers to be removed from the vector page
authorRussell King <rmk+kernel@arm.linux.org.uk>
Tue, 23 Jul 2013 17:37:00 +0000 (18:37 +0100)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Wed, 31 Jul 2013 21:01:48 +0000 (22:01 +0100)
commitf6f91b0d9fd971c630cef908dde8fe8795aefbf8
tree54032cefa513a3ae63971998caa90eea4736180c
parente39e3f3ebfef03450cf7bfa7a974a8c61f7980c8
ARM: allow kuser helpers to be removed from the vector page

Provide a kernel configuration option to allow the kernel user helpers
to be removed from the vector page, thereby preventing their use with
ROP (return orientated programming) attacks.  This option is only
visible for CPU architectures which natively support all the operations
which kernel user helpers would normally provide, and must be enabled
with caution.

Cc: <stable@vger.kernel.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/kernel/entry-armv.S
arch/arm/kernel/traps.c
arch/arm/mm/Kconfig