From 74251714cc1c2f102c355ddd21e732b075e4ce05 Mon Sep 17 00:00:00 2001
From: Alan Coopersmith <alan.coopersmith@oracle.com>
Date: Sun, 29 Mar 2026 12:39:53 -0700
Subject: [PATCH] [PR #2181] glx: avoid null dereference in
 validGlxFBConfigForWindow()

PR: https://github.com/X11Libre/xserver/pull/2181
---
 glx/glxcmds.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/glx/glxcmds.c b/glx/glxcmds.c
index 8a19959fd..3819f0598 100644
--- a/glx/glxcmds.c
+++ b/glx/glxcmds.c
@@ -133,7 +133,8 @@ validGlxFBConfigForWindow(ClientPtr client, __GLXconfig * config,
     BUG_RETURN_VAL(!pVisual, FALSE);
 
     /* FIXME: What exactly should we check here... */
-    if (pVisual->class != glxConvertToXVisualType(config->visualType) ||
+    if (pVisual == NULL ||
+        pVisual->class != glxConvertToXVisualType(config->visualType) ||
         !(config->drawableType & GLX_WINDOW_BIT)) {
         client->errorValue = pDraw->id;
         *err = BadMatch;