From: Dan Carpenter Date: Wed, 10 Jan 2018 09:40:04 +0000 (+0300) Subject: drm/vmwgfx: Potential off by one in vmw_view_add() X-Git-Tag: v4.15-rc8~19^2~1^2 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=0d9cac0ca0429830c40fe1a4e50e60f6221fd7b6;p=linux.git drm/vmwgfx: Potential off by one in vmw_view_add() The vmw_view_cmd_to_type() function returns vmw_view_max (3) on error. It's one element beyond the end of the vmw_view_cotables[] table. My read on this is that it's possible to hit this failure. header->id comes from vmw_cmd_check() and it's a user controlled number between 1040 and 1225 so we can hit that error. But I don't have the hardware to test this code. Fixes: d80efd5cb3de ("drm/vmwgfx: Initial DX support") Signed-off-by: Dan Carpenter Reviewed-by: Thomas Hellstrom Cc: --- diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c index 21c62a34e558..87e8af5776a3 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c @@ -2731,6 +2731,8 @@ static int vmw_cmd_dx_view_define(struct vmw_private *dev_priv, } view_type = vmw_view_cmd_to_type(header->id); + if (view_type == vmw_view_max) + return -EINVAL; cmd = container_of(header, typeof(*cmd), header); ret = vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface, user_surface_converter,