check null in toplevel_from_popup

managed to SEGFAULT the server by trying to create a popup
without setting a parent first.

Not sure if this is dwl or wlroots issue, so also opened a ticket upstream: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/3811

1 files changed, 3 insertions, 1 deletions

diff --git a/client.h b/client.h
index 49982e0..38330d5 100644
--- a/client.h
+++ b/client.h
@@ -304,7 +304,9 @@ toplevel_from_popup(struct wlr_xdg_popup *popup)
 	while (1) {
 		switch (surface->role) {
 		case WLR_XDG_SURFACE_ROLE_POPUP:
-			if (wlr_surface_is_layer_surface(surface->popup->parent))
+			if (!surface->popup->parent)
+				return NULL;
+			else if (wlr_surface_is_layer_surface(surface->popup->parent))
 				return wlr_layer_surface_v1_from_wlr_surface(surface->popup->parent)->data;
 			else if (!wlr_surface_is_xdg_surface(surface->popup->parent))
 				return NULL;