From owner-freebsd-net  Thu Jan  3 22:45:12 2002
Delivered-To: freebsd-net@freebsd.org
Received: from InterJet.dellroad.org (adsl-63-194-81-26.dsl.snfc21.pacbell.net [63.194.81.26])
	by hub.freebsd.org (Postfix) with ESMTP id 1AFD037B405
	for <freebsd-net@FreeBSD.ORG>; Thu,  3 Jan 2002 22:45:06 -0800 (PST)
Received: from arch20m.dellroad.org (arch20m.dellroad.org [10.1.1.20])
	by InterJet.dellroad.org (8.9.1a/8.9.1) with ESMTP id WAA58097;
	Thu, 3 Jan 2002 22:34:04 -0800 (PST)
Received: (from archie@localhost)
	by arch20m.dellroad.org (8.11.6/8.11.6) id g046Y5N23209;
	Thu, 3 Jan 2002 22:34:05 -0800 (PST)
	(envelope-from archie)
From: Archie Cobbs <archie@dellroad.org>
Message-Id: <200201040634.g046Y5N23209@arch20m.dellroad.org>
Subject: Re: netgraph kernel panic
In-Reply-To: <20020104043335.GA87710@cairo.zsat.net> "from Scott Lamb at Jan
 3, 2002 10:33:35 pm"
To: Scott Lamb <slamb@slamb.org>
Date: Thu, 3 Jan 2002 22:34:05 -0800 (PST)
Cc: freebsd-net@FreeBSD.ORG
X-Mailer: ELM [version 2.4ME+ PL88 (25)]
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Type: text/plain; charset=US-ASCII
Sender: owner-freebsd-net@FreeBSD.ORG
Precedence: bulk
List-ID: <freebsd-net.FreeBSD.ORG>
List-Archive: <http://docs.freebsd.org/mail/> (Web Archive)
List-Help: <mailto:majordomo@FreeBSD.ORG?subject=help> (List Instructions)
List-Subscribe: <mailto:majordomo@FreeBSD.ORG?subject=subscribe%20freebsd-net>
List-Unsubscribe: <mailto:majordomo@FreeBSD.ORG?subject=unsubscribe%20freebsd-net>
X-Loop: FreeBSD.org

Scott Lamb writes:
> FreeBSD 4.5-PRERELEASE (as of a few days ago) is crashing consistently
> when I try to initiate a PPTP connection to with mpd-netgraph 3.3 (from
> ports).

This is due to a problem caused by the peer's "outside" PPTP IP address
(the one from mpd.links) being equal to its "inside" IP address (the
one from "set ipcp ranges ...").

Make those different and it should stop crashing. Also, apply
the patch below to prevent it from happening again.

-Archie

__________________________________________________________________________
Archie Cobbs     *     Packet Design     *     http://www.packetdesign.com

Index: ipcp.c
===================================================================
RCS file: /home/cvs/archie/mpd/src/ipcp.c,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -r1.2 -r1.3
--- ipcp.c	2001/04/12 17:03:31	1.2
+++ ipcp.c	2001/12/16 03:47:25	1.3
@@ -19,6 +19,7 @@
 #include "custom.h"
 #include "msg.h"
 #include "ngfunc.h"
+#include "pptp.h"
 
 #include <netgraph.h>
 #include <sys/mbuf.h>
@@ -607,7 +608,7 @@
 	  switch (mode) {
 	    case MODE_REQ:
 	      if (!IpAddrInRange(&ipcp->conf.peer_allow, *ip) || !ip->s_addr) {
-		if (ipcp->peer_addr.s_addr == 0)
+nak_ip:		if (ipcp->peer_addr.s_addr == 0)
 		  Log(LG_IPCP, ("   %s", "no IP address available for peer!"));
 		if (Enabled(&ipcp->conf.options, IPCP_CONF_PRETENDIP)) {
 		  Log(LG_IPCP, ("   pretending that %s is OK, will ignore",
@@ -620,6 +621,17 @@
 		Log(LG_IPCP, ("   NAKing with %s", inet_ntoa(*ip)));
 		FsmNak(fp, opt);
 		break;
+	      }
+	      if (bund->links[0]->phys->type == &gPptpPhysType) {
+		struct in_addr pip;
+
+		lnk = bund->links[0];
+		pip = PptpGetPeerIp();
+		if (ip->s_addr == pip.s_addr) {
+		  Log(LG_IPCP,
+		    ("   Same as PPTP IP; would cause routing loop"));
+		  goto nak_ip;
+		}
 	      }
 	      Log(LG_IPCP, ("   %s is OK", inet_ntoa(*ip)));
 	      ipcp->peer_addr = *ip;

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message