From owner-svn-src-all@FreeBSD.ORG  Mon Oct 25 06:16:27 2010
Return-Path: <owner-svn-src-all@FreeBSD.ORG>
Delivered-To: svn-src-all@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id CA10C106566B;
	Mon, 25 Oct 2010 06:16:27 +0000 (UTC)
	(envelope-from kevlo@FreeBSD.org)
Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c])
	by mx1.freebsd.org (Postfix) with ESMTP id B7B648FC13;
	Mon, 25 Oct 2010 06:16:27 +0000 (UTC)
Received: from svn.freebsd.org (localhost [127.0.0.1])
	by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id o9P6GRPX052896;
	Mon, 25 Oct 2010 06:16:27 GMT (envelope-from kevlo@svn.freebsd.org)
Received: (from kevlo@localhost)
	by svn.freebsd.org (8.14.3/8.14.3/Submit) id o9P6GR5R052894;
	Mon, 25 Oct 2010 06:16:27 GMT (envelope-from kevlo@svn.freebsd.org)
Message-Id: <201010250616.o9P6GR5R052894@svn.freebsd.org>
From: Kevin Lo <kevlo@FreeBSD.org>
Date: Mon, 25 Oct 2010 06:16:27 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
	svn-src-stable@freebsd.org, svn-src-stable-8@freebsd.org
X-SVN-Group: stable-8
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: 
Subject: svn commit: r214316 - stable/8/sys/fs/msdosfs
X-BeenThere: svn-src-all@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: "SVN commit messages for the entire src tree \(except for &quot;
	user&quot; and &quot; projects&quot; \)" <svn-src-all.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-all>,
	<mailto:svn-src-all-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-all>
List-Post: <mailto:svn-src-all@freebsd.org>
List-Help: <mailto:svn-src-all-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-all>,
	<mailto:svn-src-all-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 25 Oct 2010 06:16:27 -0000

Author: kevlo
Date: Mon Oct 25 06:16:27 2010
New Revision: 214316
URL: http://svn.freebsd.org/changeset/base/214316

Log:
  MFC r214001:
  Fix a possible, but very unlikely race where the directory dirent is
  moved to the location that was used by ".." entry.

Modified:
  stable/8/sys/fs/msdosfs/msdosfs_lookup.c

Modified: stable/8/sys/fs/msdosfs/msdosfs_lookup.c
==============================================================================
--- stable/8/sys/fs/msdosfs/msdosfs_lookup.c	Mon Oct 25 05:37:12 2010	(r214315)
+++ stable/8/sys/fs/msdosfs/msdosfs_lookup.c	Mon Oct 25 06:16:27 2010	(r214316)
@@ -594,10 +594,15 @@ msdosfs_deget_dotdot(struct vnode *vp, u
 	vfs_unbusy(mp);
 	if (error == 0)
 		*rvp = DETOV(rdp);
-	vn_lock(vp, ltype | LK_RETRY);
+	if (*rvp != vp)
+		vn_lock(vp, ltype | LK_RETRY);
 	if (vp->v_iflag & VI_DOOMED) {
-		if (error == 0)
-			vput(*rvp);
+		if (error == 0) {
+			if (*rvp == vp)
+				vunref(*rvp);
+			else
+				vput(*rvp);
+		}
 		error = ENOENT;
 	}
 	return (error);