From 73ab72517b61ce4b27ceddec47dd5d6edafb556a Mon Sep 17 00:00:00 2001 From: Murray McAllister Date: Mon, 27 Mar 2017 11:12:53 +0200 Subject: [PATCH] drm/vmwgfx: NULL pointer dereference in vmw_surface_define_ioctl() commit 36274ab8c596f1240c606bb514da329add2a1bcd upstream. Before memory allocations vmw_surface_define_ioctl() checks the upper-bounds of a user-supplied size, but does not check if the supplied size is 0. Add check to avoid NULL pointer dereferences. Signed-off-by: Murray McAllister Reviewed-by: Sinclair Yeh Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/vmwgfx/vmwgfx_surface.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c index b445ce9..f410502 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c @@ -716,8 +716,8 @@ int vmw_surface_define_ioctl(struct drm_device *dev, void *data, for (i = 0; i < DRM_VMW_MAX_SURFACE_FACES; ++i) num_sizes += req->mip_levels[i]; - if (num_sizes > DRM_VMW_MAX_SURFACE_FACES * - DRM_VMW_MAX_MIP_LEVELS) + if (num_sizes > DRM_VMW_MAX_SURFACE_FACES * DRM_VMW_MAX_MIP_LEVELS || + num_sizes == 0) return -EINVAL; size = vmw_user_surface_size + 128 + -- 2.7.4