From owner-svn-src-head@FreeBSD.ORG  Sun Apr 19 22:16:19 2009
Return-Path: <owner-svn-src-head@FreeBSD.ORG>
Delivered-To: svn-src-head@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id D4F4A106566B;
	Sun, 19 Apr 2009 22:16:19 +0000 (UTC)
	(envelope-from rwatson@FreeBSD.org)
Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c])
	by mx1.freebsd.org (Postfix) with ESMTP id C3A3D8FC16;
	Sun, 19 Apr 2009 22:16:19 +0000 (UTC)
	(envelope-from rwatson@FreeBSD.org)
Received: from svn.freebsd.org (localhost [127.0.0.1])
	by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id n3JMGJr7021987;
	Sun, 19 Apr 2009 22:16:19 GMT (envelope-from rwatson@svn.freebsd.org)
Received: (from rwatson@localhost)
	by svn.freebsd.org (8.14.3/8.14.3/Submit) id n3JMGJAZ021986;
	Sun, 19 Apr 2009 22:16:19 GMT (envelope-from rwatson@svn.freebsd.org)
Message-Id: <200904192216.n3JMGJAZ021986@svn.freebsd.org>
From: Robert Watson <rwatson@FreeBSD.org>
Date: Sun, 19 Apr 2009 22:16:19 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
	svn-src-head@freebsd.org
X-SVN-Group: head
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: 
Subject: svn commit: r191285 - head/sys/netinet
X-BeenThere: svn-src-head@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: SVN commit messages for the src tree for head/-current
	<svn-src-head.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-head>,
	<mailto:svn-src-head-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-head>
List-Post: <mailto:svn-src-head@freebsd.org>
List-Help: <mailto:svn-src-head-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-head>,
	<mailto:svn-src-head-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 19 Apr 2009 22:16:20 -0000

Author: rwatson
Date: Sun Apr 19 22:16:19 2009
New Revision: 191285
URL: http://svn.freebsd.org/changeset/base/191285

Log:
  Protect against some writer-writer races in in_control() by acquiring
  the interface address list lock around interface address list
  modifications.  More to do here.
  
  MFC after:	2 weeks

Modified:
  head/sys/netinet/in.c

Modified: head/sys/netinet/in.c
==============================================================================
--- head/sys/netinet/in.c	Sun Apr 19 22:05:39 2009	(r191284)
+++ head/sys/netinet/in.c	Sun Apr 19 22:16:19 2009	(r191285)
@@ -330,14 +330,12 @@ in_control(struct socket *so, u_long cmd
 			 * Protect from ipintr() traversing address list
 			 * while we're modifying it.
 			 */
-			s = splnet();
 			ifa = &ia->ia_ifa;
 			IFA_LOCK_INIT(ifa);
 			ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
 			ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
 			ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
 			ifa->ifa_refcnt = 1;
-			TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link);
 
 			ia->ia_sockmask.sin_len = 8;
 			ia->ia_sockmask.sin_family = AF_INET;
@@ -347,6 +345,10 @@ in_control(struct socket *so, u_long cmd
 			}
 			ia->ia_ifp = ifp;
 
+			IF_ADDR_LOCK(ifp);
+			TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link);
+			IF_ADDR_UNLOCK(ifp);
+			s = splnet();
 			TAILQ_INSERT_TAIL(&V_in_ifaddrhead, ia, ia_link);
 			splx(s);
 			iaIsNew = 1;
@@ -512,8 +514,10 @@ in_control(struct socket *so, u_long cmd
 	 * Protect from ipintr() traversing address list while we're modifying
 	 * it.
 	 */
-	s = splnet();
+	IF_ADDR_LOCK(ifp);
 	TAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifa_link);
+	IF_ADDR_UNLOCK(ifp);
+	s = splnet();
 	TAILQ_REMOVE(&V_in_ifaddrhead, ia, ia_link);
 	if (ia->ia_addr.sin_family == AF_INET) {
 		LIST_REMOVE(ia, ia_hash);