arch: Move CONFIG_DEBUG_RODATA and CONFIG_SET_MODULE_RONX to be common

There are multiple architectures that support CONFIG_DEBUG_RODATA and
CONFIG_SET_MODULE_RONX. These options also now have the ability to be
turned off at runtime. Move these to an architecture independent
location and make these options def_bool y for almost all of those
arches.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
diff --git a/arch/Kconfig b/arch/Kconfig
index 99839c2..3f8b8be 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -781,4 +781,38 @@
 	  the stack to map directly to the KASAN shadow map using a formula
 	  that is incorrect if the stack is in vmalloc space.
 
+config ARCH_OPTIONAL_KERNEL_RWX
+	def_bool n
+
+config ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
+	def_bool n
+
+config ARCH_HAS_STRICT_KERNEL_RWX
+	def_bool n
+
+config DEBUG_RODATA
+	bool "Make kernel text and rodata read-only" if ARCH_OPTIONAL_KERNEL_RWX
+	depends on ARCH_HAS_STRICT_KERNEL_RWX
+	default !ARCH_OPTIONAL_KERNEL_RWX || ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
+	help
+	  If this is set, kernel text and rodata memory will be made read-only,
+	  and non-text memory will be made non-executable. This provides
+	  protection against certain security exploits (e.g. executing the heap
+	  or modifying text)
+
+	  These features are considered standard security practice these days.
+	  You should say Y here in almost all cases.
+
+config ARCH_HAS_STRICT_MODULE_RWX
+	def_bool n
+
+config DEBUG_SET_MODULE_RONX
+	bool "Set loadable kernel module data as NX and text as RO" if ARCH_OPTIONAL_KERNEL_RWX
+	depends on ARCH_HAS_STRICT_MODULE_RWX && MODULES
+	default !ARCH_OPTIONAL_KERNEL_RWX || ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
+	help
+	  If this is set, module text and rodata memory will be made read-only,
+	  and non-text memory will be made non-executable. This provides
+	  protection against certain security exploits (e.g. writing to text)
+
 source "kernel/gcov/Kconfig"