backend/drm: fix crash in init_drm_surface

Closes: https://gitlab.freedesktop.org/wlroots/wlroots/-/issues/3434

1 files changed, 2 insertions, 1 deletions

diff --git a/backend/drm/renderer.c b/backend/drm/renderer.c
index 60155313..9e1de3d0 100644
--- a/backend/drm/renderer.c
+++ b/backend/drm/renderer.c
@@ -61,7 +61,8 @@ static void finish_drm_surface(struct wlr_drm_surface *surf) {
 bool init_drm_surface(struct wlr_drm_surface *surf,
 		struct wlr_drm_renderer *renderer, int width, int height,
 		const struct wlr_drm_format *drm_format) {
-	if (surf->swapchain->width == width && surf->swapchain->height == height) {
+	if (surf->swapchain != NULL && surf->swapchain->width == width &&
+			surf->swapchain->height == height) {
 		return true;
 	}