Re: [PATCH] powerpc: Default to enabling STRICT_KERNEL_RWX
From: Christophe LEROY <hidden>
Date: 2017-10-05 07:49:19
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Le 05/10/2017 à 05:45, Kees Cook a écrit :
When available, CONFIG_KERNEL_RWX should be default-enabled.
On PPC32, this option implies deactivating BATs and/or LTLB mapping of the linear kernel address space, hence a significant performance degradation. So at least on PPC32, it should remain unselected by default. Christophe
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Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <redacted> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Kees Cook <redacted> --- arch/powerpc/Kconfig | 1 + 1 file changed, 1 insertion(+)diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 809c468edab1..9a549bbfc278 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig@@ -178,6 +178,7 @@ config PPC select HAVE_ARCH_TRACEHOOK select ARCH_HAS_STRICT_KERNEL_RWX if ((PPC_BOOK3S_64 || PPC32) && !RELOCATABLE && !HIBERNATION) select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX + select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT select HAVE_CBPF_JIT if !PPC64 select HAVE_CONTEXT_TRACKING if PPC64 select HAVE_DEBUG_KMEMLEAK