Re: [patch V4 part 1 19/36] x86/entry: Exclude low level entry code from sanitizing

From: Brian Gerst
Date: Tue May 05 2020 - 16:39:15 EST


On Tue, May 5, 2020 at 10:13 AM Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:
>
> The sanitizers are not really applicable to the fragile low level entry
> code. code. Entry code needs to carefully setup a normal 'runtime'
> environment.
>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> ---
> arch/x86/entry/Makefile | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> --- a/arch/x86/entry/Makefile
> +++ b/arch/x86/entry/Makefile
> @@ -3,6 +3,14 @@
> # Makefile for the x86 low level entry code
> #
>
> +KASAN_SANITIZE := n
> +UBSAN_SANITIZE := n
> +KCOV_INSTRUMENT := n
> +
> +CFLAGS_REMOVE_common.o = $(CC_FLAGS_FTRACE) -fstack-protector -fstack-protector-strong
> +CFLAGS_REMOVE_syscall_32.o = $(CC_FLAGS_FTRACE) -fstack-protector -fstack-protector-strong
> +CFLAGS_REMOVE_syscall_64.o = $(CC_FLAGS_FTRACE) -fstack-protector -fstack-protector-strong

Is this necessary for syscall_*.o? They just contain the syscall
tables (ie. data).

--
Brian Gerst