The patch below does not apply to the 5.13-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From c88e2647c5bb45d04dc4302018ebe6ebbf331823 Mon Sep 17 00:00:00 2001
From: Kees Cook keescook@chromium.org Date: Thu, 17 Jun 2021 14:33:01 -0700 Subject: [PATCH] drm/i915/display: Do not zero past infoframes.vsc MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit
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().
Fixes: 1b404b7dbb10 ("drm/i915/dp: Read out DP SDPs") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook keescook@chromium.org Reviewed-by: José Roberto de Souza jose.souza@intel.com Signed-off-by: José Roberto de Souza jose.souza@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20210617213301.1824728-1-keesc...
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;