On Wed, May 11, 2022 at 6:37 PM Timur Tabi <ttabi@xxxxxxxxxx> wrote:
>
> This check determines whether a given address is part of
> image 0 or image 1. Image 1 starts at offset image0_size,
> so that address should be included.
>
> Fixes: 4d4e9907ff572 ("drm/nouveau/bios: guard against out-of-bounds accesses to image")
> Signed-off-by: Timur Tabi <ttabi@xxxxxxxxxx>
> ---
> drivers/gpu/drm/nouveau/nvkm/subdev/bios/base.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/bios/base.c b/drivers/gpu/drm/nouveau/nvkm/subdev/bios/base.c
> index 64e423dddd9e..6c318e41bde0 100644
> --- a/drivers/gpu/drm/nouveau/nvkm/subdev/bios/base.c
> +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/bios/base.c
> @@ -33,7 +33,7 @@ nvbios_addr(struct nvkm_bios *bios, u32 *addr, u8 size)
> {
> u32 p = *addr;
>
> - if (*addr > bios->image0_size && bios->imaged_addr) {
> + if (*addr >= bios->image0_size && bios->imaged_addr) {
> *addr -= bios->image0_size;
> *addr += bios->imaged_addr;
> }
> --
> 2.36.0
>
Reviewed-by: Karol Herbst <kherbst@xxxxxxxxxx>
I don't like how this could fail for values spanning both images, but
at least this looks more correct.
I think in the future we should keep a copy without that gap on the
host side to make access to the vbios image cheaper. What do you say
Ben?
