Re: [PATCH v3 02/11] arm64: Make use of is_compat_task instead of hardcoding this test

[Kees Cook]

On Wed, Apr 17, 2019 at 12:25 AM Alexandre Ghiti <alex@xxxxxxxx> wrote:
>
> Each architecture has its own way to determine if a task is a compat task,
> by using is_compat_task in arch_mmap_rnd, it allows more genericity and
> then it prepares its moving to mm/.
>
> Signed-off-by: Alexandre Ghiti <alex@xxxxxxxx>

Acked-by: Kees Cook <keescook@xxxxxxxxxxxx>

-Kees

> ---
>  arch/arm64/mm/mmap.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c
> index 842c8a5fcd53..ed4f9915f2b8 100644
> --- a/arch/arm64/mm/mmap.c
> +++ b/arch/arm64/mm/mmap.c
> @@ -54,7 +54,7 @@ unsigned long arch_mmap_rnd(void)
>         unsigned long rnd;
>
>  #ifdef CONFIG_COMPAT
> -       if (test_thread_flag(TIF_32BIT))
> +       if (is_compat_task())
>                 rnd = get_random_long() & ((1UL << mmap_rnd_compat_bits) - 1);
>         else
>  #endif
> --
> 2.20.1
>


-- 
Kees Cook