Subject: Re: [PATCH 3/3 V13] RO/NX protection for loadable kernel

From: Kees Cook <[email-masked]>
Date: Wed, 8 Dec 2010 14:19:51 -0800

On Fri, Nov 26, 2010 at 06:23:55PM +0100, mat wrote:
> could you try the attached patch ?
> 
> on module load, we sort the __jump_table section. So we should make it
> writable.
> 
> 
> Matthieu

> diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h
> index f52d42e..574dbc2 100644
> --- a/arch/x86/include/asm/jump_label.h
> +++ b/arch/x86/include/asm/jump_label.h
> @@ -14,7 +14,7 @@
>  	do {							\
>  		asm goto("1:"					\
>  			JUMP_LABEL_INITIAL_NOP			\
> -			".pushsection __jump_table,  \"a\" \n\t"\
> +			".pushsection __jump_table,  \"aw\" \n\t"\
>  			_ASM_PTR "1b, %l[" #label "], %c0 \n\t" \
>  			".popsection \n\t"			\
>  			: :  "i" (key) :  : label);		\

Acked-by: Kees Cook <[email-masked]>

Can this please get committed to tip?

Thanks,

-Kees

-- 
Kees Cook
Ubuntu Security Team