[PATCH 2/3] [RFC] drm/i915/gvt: Fix opregion_header->signature size

[Jani Nikula]

On Mon, 24 Mar 2025, Nicolas Chauvet <kwizart at gmail.com> wrote:
> Enlarge the signature field to accept the string termination.
>
> Cc: stable at vger.kernel.org
> Fixes: 93615d59912 ("Revert drm/i915/gvt: Fix out-of-bounds buffer write into opregion->signature[]")
> Signed-off-by: Nicolas Chauvet <kwizart at gmail.com>

Nope, can't do that. The packed struct is used for parsing data in
memory.

BR,
Jani.


> ---
>  drivers/gpu/drm/i915/gvt/opregion.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/gvt/opregion.c b/drivers/gpu/drm/i915/gvt/opregion.c
> index 9a8ead6039e2..0f11cd6ba383 100644
> --- a/drivers/gpu/drm/i915/gvt/opregion.c
> +++ b/drivers/gpu/drm/i915/gvt/opregion.c
> @@ -43,7 +43,7 @@
>  #define DEVICE_TYPE_EFP4   0x10
>  
>  struct opregion_header {
> -	u8 signature[16];
> +	u8 signature[32];
>  	u32 size;
>  	u32 opregion_ver;
>  	u8 bios_ver[32];

-- 
Jani Nikula, Intel