ARM: add DEBUG_SET_MODULE_RONX option to Kconfig

Now that all the page setting infrastructure is in place,
Add the DEBUG_SET_MODULE_RONX to the ARM debugging Kconfig.
When turned on, data sections for modules will be marked as NX
and read only sections will be marked as such.

Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 0603a6a..1043cb8 100644 (file)
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -1162,4 +1162,15 @@ config PID_IN_CONTEXTIDR
          additional instructions during context switch. Say Y here only if you
          are planning to use hardware trace tools with this kernel.
 
+config DEBUG_SET_MODULE_RONX
+       bool "Set loadable kernel module data as NX and text as RO"
+       depends on MODULES
+       ---help---
+         This option helps catch unintended modifications to loadable
+         kernel module's text and read-only data. It also prevents execution
+         of module data. Such protection may interfere with run-time code
+         patching and dynamic kernel tracing - and they might also protect
+         against certain classes of kernel exploits.
+         If in doubt, say "N".
+
 endmenu