From owner-freebsd-bugs@FreeBSD.ORG  Sat Jan 24 13:00:31 2004
Return-Path: <owner-freebsd-bugs@FreeBSD.ORG>
Delivered-To: freebsd-bugs@hub.freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 6F86816A4CE
	for <freebsd-bugs@hub.freebsd.org>;
	Sat, 24 Jan 2004 13:00:31 -0800 (PST)
Received: from freefall.freebsd.org (freefall.freebsd.org [216.136.204.21])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 54A9C43D49
	for <freebsd-bugs@hub.freebsd.org>;
	Sat, 24 Jan 2004 13:00:29 -0800 (PST)
	(envelope-from gnats@FreeBSD.org)
Received: from freefall.freebsd.org (gnats@localhost [127.0.0.1])
	i0OL0TFR034806	for <freebsd-bugs@freefall.freebsd.org>;
	Sat, 24 Jan 2004 13:00:29 -0800 (PST)
	(envelope-from gnats@freefall.freebsd.org)
Received: (from gnats@localhost)
	by freefall.freebsd.org (8.12.10/8.12.10/Submit) id i0OL0TQG034805;
	Sat, 24 Jan 2004 13:00:29 -0800 (PST)
	(envelope-from gnats)
Resent-Date: Sat, 24 Jan 2004 13:00:29 -0800 (PST)
Resent-Message-Id: <200401242100.i0OL0TQG034805@freefall.freebsd.org>
Resent-From: FreeBSD-gnats-submit@FreeBSD.org (GNATS Filer)
Resent-To: freebsd-bugs@FreeBSD.org
Resent-Reply-To: FreeBSD-gnats-submit@FreeBSD.org,
	Stephan Uphoff <ups@tree.com>
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 83C1116A4CE
	for <freebsd-gnats-submit@FreeBSD.org>;
	Sat, 24 Jan 2004 12:52:39 -0800 (PST)
Received: from www.freebsd.org (www.freebsd.org [216.136.204.117])
	by mx1.FreeBSD.org (Postfix) with ESMTP id BA8D843D1F
	for <freebsd-gnats-submit@FreeBSD.org>;
	Sat, 24 Jan 2004 12:52:38 -0800 (PST)
	(envelope-from nobody@FreeBSD.org)
Received: from www.freebsd.org (localhost [127.0.0.1])
	by www.freebsd.org (8.12.10/8.12.10) with ESMTP id i0OKqcdL044310
	for <freebsd-gnats-submit@FreeBSD.org>;
	Sat, 24 Jan 2004 12:52:38 -0800 (PST)
	(envelope-from nobody@www.freebsd.org)
Received: (from nobody@localhost)
	by www.freebsd.org (8.12.10/8.12.10/Submit) id i0OKqcHc044309;
	Sat, 24 Jan 2004 12:52:38 -0800 (PST)
	(envelope-from nobody)
Message-Id: <200401242052.i0OKqcHc044309@www.freebsd.org>
Date: Sat, 24 Jan 2004 12:52:38 -0800 (PST)
From: Stephan Uphoff <ups@tree.com>
To: freebsd-gnats-submit@FreeBSD.org
X-Send-Pr-Version: www-2.0
Subject: kern/61849: Possible use of kqueue_scan on stack marker while stack
	swapped out
X-BeenThere: freebsd-bugs@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: Bug reports <freebsd-bugs.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-bugs>,
	<mailto:freebsd-bugs-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-bugs>
List-Post: <mailto:freebsd-bugs@freebsd.org>
List-Help: <mailto:freebsd-bugs-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-bugs>,
	<mailto:freebsd-bugs-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sat, 24 Jan 2004 21:00:31 -0000


>Number:         61849
>Category:       kern
>Synopsis:       Possible use of kqueue_scan on stack marker while stack swapped out
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sat Jan 24 13:00:28 PST 2004
>Closed-Date:
>Last-Modified:
>Originator:     Stephan Uphoff
>Release:        current
>Organization:
>Environment:
N/A  
>Description:
kqueue_scan() puts a marker element on the event list.
The marker element lives on the stack.
kqueue_scan() can block (example copyout) and its stack can
be swapped out.
The marker element might be accessed while the stack is swapped out.


>How-To-Repeat:
      
>Fix:
Use PROC_LOCK/PROC_UNLOCK to prevent swapping or use 
non stack memory for the marker element.

>Release-Note:
>Audit-Trail:
>Unformatted: