Re: [PATCH] x86,vdso: Set VM_MAYREAD for the vvar vma

[Andy Lutomirski]

On Fri, Jul 25, 2014 at 4:27 PM, Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote:
> AFAIK this has no effect whatsoever unless x86 suddenly turns into a
> nommu architecture.  Nonetheless, not setting it is suspicious.

Sorry, forgot to mention: this is based on tip/x86/vdso.

--Andy

>
> Reported-by: Nathan Lynch <Nathan_Lynch@xxxxxxxxxx>
> Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
> ---
>  arch/x86/vdso/vma.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/vdso/vma.c b/arch/x86/vdso/vma.c
> index dbef622..970463b 100644
> --- a/arch/x86/vdso/vma.c
> +++ b/arch/x86/vdso/vma.c
> @@ -138,7 +138,7 @@ static int map_vdso(const struct vdso_image *image, bool calculate_addr)
>         vma = _install_special_mapping(mm,
>                                        addr,
>                                        -image->sym_vvar_start,
> -                                      VM_READ,
> +                                      VM_READ|VM_MAYREAD,
>                                        &vvar_mapping);
>
>         if (IS_ERR(vma)) {
> --
> 1.9.3
>



-- 
Andy Lutomirski
AMA Capital Management, LLC
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/