NetBSD Problem Report #43100
From www@NetBSD.org Fri Apr 2 03:54:01 2010
Return-Path: <www@NetBSD.org>
Received: from mail.netbsd.org (mail.netbsd.org [204.152.190.11])
by www.NetBSD.org (Postfix) with ESMTP id 9891C63B86C
for <gnats-bugs@gnats.NetBSD.org>; Fri, 2 Apr 2010 03:54:01 +0000 (UTC)
Message-Id: <20100402035401.5C64763B11D@www.NetBSD.org>
Date: Fri, 2 Apr 2010 03:54:01 +0000 (UTC)
From: shigeru@iij.ad.jp
Reply-To: shigeru@iij.ad.jp
To: gnats-bugs@NetBSD.org
Subject: 'pr->ndpr_refcnt' should be inclemented in in6_ifattach_linklocal()@sys/netinet6/in6_ifattach.c
X-Send-Pr-Version: www-1.0
>Number: 43100
>Category: kern
>Synopsis: 'pr->ndpr_refcnt' should be inclemented in in6_ifattach_linklocal()@sys/netinet6/in6_ifattach.c
>Confidential: no
>Severity: non-critical
>Priority: low
>Responsible: kern-bug-people
>State: open
>Class: sw-bug
>Submitter-Id: net
>Arrival-Date: Fri Apr 02 03:55:00 +0000 2010
>Originator: YAMAMOTO, Shigeru
>Release: NetBSD 5.0.2
>Organization:
Internet Initiative Japan Inc.
>Environment:
NetBSD triton.iij.ad.jp 5.0.2 NetBSD 5.0.2 (GENERIC) #0: Sat Feb 6 17:53:27 UTC 2010 builds@b7.netbsd.org:/home/builds/ab/netbsd-5-0-2-RELEASE/i386/201002061851Z-obj/home/builds/ab/netbsd-5-0-2-RELEASE/src/sys/arch/i386/compile/GENERIC i386
>Description:
We have 2 way to set IPv6 linklocal address.
One is 'in6_control1()@sys/netinet6/in6.c' which is called by ioctl().
Another is 'in6_ifattach_linklocal()@sys/netinet6/in6_ifattach.c' which is called by in6_ifattach()@sys/netinet6/in6_ifattach.c.
when comparing in6_controll() and in6_ifattach_linklocal(), there is a difference about inclementing 'pr->ndpr_refcnt'.
in6_controll() inclements 'pr->ndpr_refcnt'.
but, in6_ifattach_linklocal() does not inclement 'pr->ndpr_refcnt'.
I think, this difference causes reference count mismatch.
>How-To-Repeat:
1) use IPv6 enabled kernel
2) enable IPv6 on interface
# ifconfig <if> inet6 up
3) add new IPv6 linklocal address
# ifconfig <if> inet6 fe80::1
4) check 'fe80::%<if>/64' in routing table
# netstat -rn -f inet6
5) delete IPv6 linklocal address which is added at step '3)'.
# ifconfig <if> inet6 delete fe80::1
6) check 'fe80::%<if>/64' in routing table
# netstat -rn -f inet6
at step '6)', we can see that 'fe80::%<if>/64" is deleted from routing table.
In *BSD, in6_ifattach_linklocal() is same code.
So I think *BSD have same problem.
>Fix:
need fix in6_ifattach_linklocal().
this is a patch.
-------------------------------------------------------------------
--- sys/netinet6/in6_ifattach.c.orig 2008-04-24 20:38:38.000000000 +0900
+++ sys/netinet6/in6_ifattach.c 2010-04-02 11:25:11.000000000 +0900
@@ -534,6 +534,7 @@
struct in6_ifaddr *ia;
struct in6_aliasreq ifra;
struct nd_prefixctl pr0;
+ struct nd_prefix *pr = NULL;
int i, error;
/*
@@ -631,9 +632,21 @@
* address, and then reconfigure another one, the prefix is still
* valid with referring to the old link-local address.
*/
- if (nd6_prefix_lookup(&pr0) == NULL) {
- if ((error = nd6_prelist_add(&pr0, NULL, NULL)) != 0)
- return error;
+ if ((pr = nd6_prefix_lookup(&pr0)) == NULL) {
+ if ((error = nd6_prelist_add(&pr0, NULL, &pr)) != 0)
+ return (error);
+#ifdef DIAGNOSTIC
+ if (pr == NULL) {
+ panic("pr == NULL in in6_ifattach_linklocal");
+ /* NOTREACHED */
+ }
+#endif
+ }
+
+ /* relate the address to the prefix */
+ if (ia->ia6_ndpr == NULL) {
+ ia->ia6_ndpr = pr;
+ pr->ndpr_refcnt++;
}
return 0;
-------------------------------------------------------------------
(Contact us)
$NetBSD: query-full-pr,v 1.39 2013/11/01 18:47:49 spz Exp $
$NetBSD: gnats_config.sh,v 1.8 2006/05/07 09:23:38 tsutsui Exp $
Copyright © 1994-2007
The NetBSD Foundation, Inc. ALL RIGHTS RESERVED.