From owner-cvs-src-old@FreeBSD.ORG  Wed Feb 25 15:04:36 2009
Return-Path: <owner-cvs-src-old@FreeBSD.ORG>
Delivered-To: cvs-src-old@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 8828010656F2
	for <cvs-src-old@freebsd.org>; Wed, 25 Feb 2009 15:04:36 +0000 (UTC)
	(envelope-from rwatson@FreeBSD.org)
Received: from repoman.freebsd.org (repoman.freebsd.org
	[IPv6:2001:4f8:fff6::29])
	by mx1.freebsd.org (Postfix) with ESMTP id 7045D8FC1B
	for <cvs-src-old@freebsd.org>; Wed, 25 Feb 2009 15:04:36 +0000 (UTC)
	(envelope-from rwatson@FreeBSD.org)
Received: from repoman.freebsd.org (localhost [127.0.0.1])
	by repoman.freebsd.org (8.14.3/8.14.3) with ESMTP id n1PF4aTu082282
	for <cvs-src-old@freebsd.org>; Wed, 25 Feb 2009 15:04:36 GMT
	(envelope-from rwatson@repoman.freebsd.org)
Received: (from svn2cvs@localhost)
	by repoman.freebsd.org (8.14.3/8.14.3/Submit) id n1PF4aJZ082281
	for cvs-src-old@freebsd.org; Wed, 25 Feb 2009 15:04:36 GMT
	(envelope-from rwatson@repoman.freebsd.org)
Message-Id: <200902251504.n1PF4aJZ082281@repoman.freebsd.org>
X-Authentication-Warning: repoman.freebsd.org: svn2cvs set sender to
	rwatson@repoman.freebsd.org using -f
From: Robert Watson <rwatson@FreeBSD.org>
Date: Wed, 25 Feb 2009 15:04:30 +0000 (UTC)
To: cvs-src-old@freebsd.org
X-FreeBSD-CVS-Branch: RELENG_7
Subject: cvs commit: src/sys/kern kern_descrip.c
X-BeenThere: cvs-src-old@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: **OBSOLETE** CVS commit messages for the src tree
	<cvs-src-old.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/cvs-src-old>,
	<mailto:cvs-src-old-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/cvs-src-old>
List-Post: <mailto:cvs-src-old@freebsd.org>
List-Help: <mailto:cvs-src-old-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/cvs-src-old>,
	<mailto:cvs-src-old-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Wed, 25 Feb 2009 15:04:40 -0000

rwatson     2009-02-25 15:04:30 UTC

  FreeBSD src repository

  Modified files:        (Branch: RELENG_7)
    sys/kern             kern_descrip.c 
  Log:
  SVN rev 189044 on 2009-02-25 15:04:30Z by rwatson
  
  Merge r188485 from head to stable/7:
  
    Modify fdcopy() so that, during fork(2), it won't copy file descriptors
    from the parent to the child process if they have an operation vector
    of &badfileops.  This narrows a set of races involving system calls that
    allocate a new file descriptor, potentially block for some extended
    period, and then return the file descriptor, when invoked by a threaded
    program that concurrently invokes fork(2).  Similar approches are used
    in both Solaris and Linux, and the wideness of this race was introduced
    in FreeBSD when we moved to a more optimistic implementation of
    accept(2) in order to simplify locking.
  
    A small race necessarily remains because the fork(2) might occur after
    the finit() in accept(2) but before the system call has returned, but
    that appears unavoidable using current APIs.  However, this race is
    vastly narrower.
  
    The fix can be validated using the newfileops_on_fork regression test.
  
    PR:           kern/130348
    Reported by:  Ivan Shcheklein <shcheklein at gmail dot com>
    Reviewed by:  jhb, kib
  
  Revision    Changes    Path
  1.313.2.16  +2 -1      src/sys/kern/kern_descrip.c