[PATCH next] riscv: Add ARCH_HAS_FORTIFY_SOURCE

[Palmer Dabbelt]

On Wed, 24 Feb 2021 23:03:03 PST (-0800), wangkefeng.wang at huawei.com wrote:
> FORTIFY_SOURCE could detect various overflows at compile and run time.
> ARCH_HAS_FORTIFY_SOURCE means that the architecture can be built and
> run with CONFIG_FORTIFY_SOURCE. Select it in RISCV.
>
> See more about this feature from commit 6974f0c4555e
> ("include/linux/string.h: add the option of fortified string.h functions").
>
> Signed-off-by: Kefeng Wang <wangkefeng.wang at huawei.com>
> ---
>  arch/riscv/Kconfig              | 1 +
>  arch/riscv/include/asm/string.h | 5 +++++
>  2 files changed, 6 insertions(+)
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 53e66347366f..fa30fbf66879 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -20,6 +20,7 @@ config RISCV
>  	select ARCH_HAS_DEBUG_VM_PGTABLE
>  	select ARCH_HAS_DEBUG_VIRTUAL if MMU
>  	select ARCH_HAS_DEBUG_WX
> +	select ARCH_HAS_FORTIFY_SOURCE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
>  	select ARCH_HAS_GIGANTIC_PAGE
>  	select ARCH_HAS_KCOV
> diff --git a/arch/riscv/include/asm/string.h b/arch/riscv/include/asm/string.h
> index 5477e7ecb6e1..909049366555 100644
> --- a/arch/riscv/include/asm/string.h
> +++ b/arch/riscv/include/asm/string.h
> @@ -23,5 +23,10 @@ extern asmlinkage void *__memmove(void *, const void *, size_t);
>  #define memcpy(dst, src, len) __memcpy(dst, src, len)
>  #define memset(s, c, n) __memset(s, c, n)
>  #define memmove(dst, src, len) __memmove(dst, src, len)
> +
> +#ifndef __NO_FORTIFY
> +#define __NO_FORTIFY /* FORTIFY_SOURCE uses __builtin_memcpy, etc. */
> +#endif
> +
>  #endif
>  #endif /* _ASM_RISCV_STRING_H */

Thanks, this is on for-next.