From aa7287efbf0e7f7ab13e46bb85ae71981e1ac3bd Mon Sep 17 00:00:00 2001
From: David Maciejak <david.maciejak@gmail.com>
Date: Thu, 9 Apr 2026 22:55:01 +0000
Subject: [PATCH] wmaker: check RCreateImage() result for _NET_WM_ICON

makeRImageFromARGBData() dereferences image->data immediately after
RCreateImage() without checking for NULL. A client that advertises a
20000x20000 icon makes RCreateImage() try a 1.6 GB malloc, on failure
wmaker segfaults.
---
 src/wmspec.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/wmspec.c b/src/wmspec.c
index 26f4a5a6..2d9b4611 100644
--- a/src/wmspec.c
+++ b/src/wmspec.c
@@ -408,6 +408,8 @@ static RImage *makeRImageFromARGBData(unsigned long *data)
 		return NULL;
 
 	image = RCreateImage(width, height, True);
+	if (!image)
+		return NULL;
 
 	for (imgdata = image->data, i = 2; i < size + 2; i++, imgdata += 4) {
 		pixel = data[i];