[Intel-gfx] [PATCH] drm/i915/display: Do not zero past infoframes.vsc

[Souza, Jose]

On Thu, 2021-06-17 at 14:33 -0700, Kees Cook wrote:
> intel_dp_vsc_sdp_unpack() was using a memset() size (36, struct dp_sdp)
> larger than the destination (24, struct drm_dp_vsc_sdp), clobbering
> fields in struct intel_crtc_state after infoframes.vsc. Use the actual
> target size for the memset().

Reviewed-by: José Roberto de Souza <jose.souza at intel.com>

> 
> Fixes: 1b404b7dbb10 ("drm/i915/dp: Read out DP SDPs")
> Cc: stable at vger.kernel.org
> Signed-off-by: Kees Cook <keescook at chromium.org>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 5c9222283044..6cc03b9e4321 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -2868,7 +2868,7 @@ static int intel_dp_vsc_sdp_unpack(struct drm_dp_vsc_sdp *vsc,
>  	if (size < sizeof(struct dp_sdp))
>  		return -EINVAL;
>  
> -	memset(vsc, 0, size);
> +	memset(vsc, 0, sizeof(*vsc));
>  
>  	if (sdp->sdp_header.HB0 != 0)
>  		return -EINVAL;