This code has been broken for ~ 20 years!

Initialise the 'fromlen' parameter for recvfrom() prior to the call, instead
of passing in a 'random' value off the stack.
This should fix the problems with ypbind on current.
I suspect the old kernel was not objecting to -ve buffer lengths.

usr.sbin/rpcbind/rpcb_svc_com.c

@@ -1,4 +1,4 @@
-/*	$NetBSD: rpcb_svc_com.c,v 1.12 2007/05/16 14:42:07 christos Exp $	*/
+/*	$NetBSD: rpcb_svc_com.c,v 1.13 2007/08/27 19:51:50 dsl Exp $	*/
 
 /*
  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
@@ -1217,6 +1217,7 @@ handle_reply(int fd, SVCXPRT *xprt)
 		goto done;
 
 	do {
+		fromlen = sizeof ss;
 		inlen = recvfrom(fd, buffer, RPC_BUF_MAX, 0,
 			    (struct sockaddr *)&ss, &fromlen);
 	} while (inlen < 0 && errno == EINTR);