From c8cb83597dae8bf181af57a86e8f9b9b781be26e Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Sun, 23 May 1999 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1999-05-23

---
 ip/ipaux.c | 4 +++-
 ip/udp.c   | 3 +--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/ip/ipaux.c b/ip/ipaux.c
index 0e04b6ffdc6b8fd8ff2ddf0715e6a5159b15c8cb..a5aaee56699d9b4b54a98ac5fb0bc9107ee0890a 100644
--- a/ip/ipaux.c
+++ b/ip/ipaux.c
@@ -260,8 +260,10 @@ v4tov6(uchar *v6, uchar *v4)
 int
 v6tov4(uchar *v4, uchar *v6)
 {
-	if(memcmp(v6, v4prefix, IPv4off) != 0)
+	if(memcmp(v6, v4prefix, IPv4off) != 0){
+		memset(v4, 0, 4);
 		return -1;
+	}
 	memmove(v4, v6 + IPv4off, IPv4addrlen);
 	return 0;
 }
diff --git a/ip/udp.c b/ip/udp.c
index 6d3fc54ed1991b5db152cfb09ce9484a631d11db..dff93c9ab5210614c155861e48ca0a2985d108ce 100644
--- a/ip/udp.c
+++ b/ip/udp.c
@@ -215,8 +215,7 @@ udpkick(Conv *c, int)
 		hnputs(uh->udpdport, c->rport);
 		if(ipcmp(c->laddr, IPnoaddr) == 0)
 			findlocalip(f, c->laddr, c->raddr);
-		if(v6tov4(uh->udpsrc, c->laddr) < 0)
-			memset(uh->udpsrc, 0, sizeof(uh->udpsrc));
+		v6tov4(uh->udpsrc, c->laddr);
 		break;
 	}
 	hnputs(uh->udpsport, c->lport);