From 6481f66b9079fd86ecb041e6760fb23bfb1de087 Mon Sep 17 00:00:00 2001
From: Poul-Henning Kamp <phk@FreeBSD.org>
Date: Tue, 28 Jun 2016 20:10:30 +0000
Subject: [PATCH] Do not coredump if the packet is too long in the global
 (non-interface associated) instance.

The result is that the packet is dropped without an indication
that smaller MTU is advisable, which is not optimal, but better
than a NULL pointer deref.

Approved by:	re (glebius)
---
 sbin/natd/natd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sbin/natd/natd.c b/sbin/natd/natd.c
index 894e82467f9..aa1628a6312 100644
--- a/sbin/natd/natd.c
+++ b/sbin/natd/natd.c
@@ -618,7 +618,7 @@ static void DoGlobal (int fd)
 	
 	if (wrote != bytes) {
 
-		if (errno == EMSGSIZE) {
+		if (errno == EMSGSIZE && mip != NULL) {
 
 			if (mip->ifMTU != -1)
 				SendNeedFragIcmp (icmpSock,