The patch below does not apply to the 4.9-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 bcd6aa7b6cbfd6f985f606c6f76046d782905820 Mon Sep 17 00:00:00 2001

From: Murray McAllister murray.mcallister@gmail.com Date: Sat, 11 May 2019 18:01:37 +1200 Subject: [PATCH] drm/vmwgfx: NULL pointer dereference from vmw_cmd_dx_view_define()

If SVGA_3D_CMD_DX_DEFINE_RENDERTARGET_VIEW is called with a surface ID of SVGA3D_INVALID_ID, the srf struct will remain NULL after vmw_cmd_res_check(), leading to a null pointer dereference in vmw_view_add().

Cc: stable@vger.kernel.org Fixes: d80efd5cb3de ("drm/vmwgfx: Initial DX support") Signed-off-by: Murray McAllister murray.mcallister@gmail.com Reviewed-by: Thomas Hellstrom thellstrom@vmware.com Signed-off-by: Thomas Hellstrom thellstrom@vmware.com

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c index 315f9efce765..b4c7553d2814 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c @@ -2427,6 +2427,10 @@ static int vmw_cmd_dx_view_define(struct vmw_private *dev_priv, return -EINVAL;

cmd = container_of(header, typeof(*cmd), header); + if (unlikely(cmd->sid == SVGA3D_INVALID_ID)) { + VMW_DEBUG_USER("Invalid surface id.\n"); + return -EINVAL; + } ret = vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface, VMW_RES_DIRTY_NONE, user_surface_converter, &cmd->sid, &srf);