From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [Bugme-new] [Bug 8284] New: IPsec anti-replay window management flaw Date: Fri, 30 Mar 2007 01:14:50 -0700 Message-ID: <20070330011450.f981a8ca.akpm@linux-foundation.org> References: <200703300806.l2U86HLU019078@fire-2.osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: "bugme-daemon@kernel-bugs.osdl.org" , didier.schrapf@alcatelaleniaspace.com To: netdev@vger.kernel.org Return-path: Received: from smtp.osdl.org ([65.172.181.24]:55196 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1945943AbXC3IPA (ORCPT ); Fri, 30 Mar 2007 04:15:00 -0400 In-Reply-To: <200703300806.l2U86HLU019078@fire-2.osdl.org> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, 30 Mar 2007 01:06:17 -0700 bugme-daemon@bugzilla.kernel.org wrote: > http://bugzilla.kernel.org/show_bug.cgi?id=8284 > > Summary: IPsec anti-replay window management flaw > Kernel Version: 2.6.20.4 > Status: NEW > Severity: normal > Owner: shemminger@osdl.org > Submitter: didier.schrapf@alcatelaleniaspace.com > > > The IPsec ESP/AH anti-replay window size is configurable, 64 being the value > recommended by RFC 2406. > Linux kernels use a 32 bit bitmap to check whether a sequence number has > already been received. > > When a packet is received, if its seq is lower than the greatest received seq, > and if the difference is greater than 32, the check doesn't work. > This constitutes a security flaw. > > The faulty code is in net/xfrm/xfrm-state.c, functions xfrm_replay_check() and > xfrm_replay_advance().