From 36bbf8affc62b0dc752fd8ac5b7b5cb4035c226b Mon Sep 17 00:00:00 2001
From: Nikita Ivanov <nikita.vyach.ivanov@gmail.com>
Date: Thu, 31 Aug 2023 18:54:10 +0200
Subject: [PATCH] Fix undefined behaviour in xytonode

Sometimes pnode->parent is NULL.
---
 dwl.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/dwl.c b/dwl.c
index 4ff5c37..c9ec812 100644
--- a/dwl.c
+++ b/dwl.c
@@ -2638,8 +2638,11 @@ xytonode(double x, double y, struct wlr_surface **psurface,
 			surface = wlr_scene_surface_from_buffer(
 					wlr_scene_buffer_from_node(node))->surface;
 		/* Walk the tree to find a node that knows the client */
-		for (pnode = node; pnode && !c; pnode = &pnode->parent->node)
+		for (pnode = node; pnode && !c; pnode = &pnode->parent->node) {
 			c = pnode->data;
+			if (!pnode->parent)
+				break;
+		}
 		if (c && c->type == LayerShell) {
 			c = NULL;
 			l = pnode->data;