From 3383778c88b3306f22d8ef648e65950b5c6a2738 Mon Sep 17 00:00:00 2001
From: Alug <alugfolie@proton.me>
Date: Mon, 27 Apr 2026 22:00:36 +0200
Subject: [PATCH] prevent buffer underflow within holepunching

---
 src/d_clisrv.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/d_clisrv.c b/src/d_clisrv.c
index e0625efd2..be32a6de0 100644
--- a/src/d_clisrv.c
+++ b/src/d_clisrv.c
@@ -1630,7 +1630,12 @@ static void CL_ReloadReceivedSavegame(void)
 static void SendAskInfo(INT32 node)
 {
 	tic_t asktime;
-	doomdata_t *netbuffer = DOOMCOM_DATA(doomcom);
+	doomdata_t *netbuffer;
+
+	if (node == -1)
+		return;
+
+	netbuffer = DOOMCOM_DATA(doomcom);
 
 	if (node != 0 && node != BROADCASTADDR &&
 			cv_rendezvousserver.string[0])