summaryrefslogtreecommitdiffstats
path: root/arch/arm/kernel/entry-armv.S
diff options
context:
space:
mode:
authorRussell King <rmk+kernel@arm.linux.org.uk>2013-07-23 18:37:00 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2013-07-31 22:01:48 +0100
commitf6f91b0d9fd971c630cef908dde8fe8795aefbf8 (patch)
tree54032cefa513a3ae63971998caa90eea4736180c /arch/arm/kernel/entry-armv.S
parente39e3f3ebfef03450cf7bfa7a974a8c61f7980c8 (diff)
downloadop-kernel-dev-f6f91b0d9fd971c630cef908dde8fe8795aefbf8.zip
op-kernel-dev-f6f91b0d9fd971c630cef908dde8fe8795aefbf8.tar.gz
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>
Diffstat (limited to 'arch/arm/kernel/entry-armv.S')
-rw-r--r--arch/arm/kernel/entry-armv.S3
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index 94caefb..d40d0ef 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -753,6 +753,7 @@ ENDPROC(__switch_to)
.endr
.endm
+#ifdef CONFIG_KUSER_HELPERS
.align 5
.globl __kuser_helper_start
__kuser_helper_start:
@@ -939,6 +940,8 @@ __kuser_helper_version: @ 0xffff0ffc
.globl __kuser_helper_end
__kuser_helper_end:
+#endif
+
THUMB( .thumb )
/*
OpenPOWER on IntegriCloud