From owner-freebsd-security@FreeBSD.ORG Fri Apr 23 16:34:48 2004 Return-Path: Delivered-To: freebsd-security@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id A635C16A4CE for ; Fri, 23 Apr 2004 16:34:48 -0700 (PDT) Received: from relay.pair.com (relay.pair.com [209.68.1.20]) by mx1.FreeBSD.org (Postfix) with SMTP id 33D7643D54 for ; Fri, 23 Apr 2004 16:34:48 -0700 (PDT) (envelope-from silby@silby.com) Received: (qmail 68179 invoked from network); 23 Apr 2004 23:34:47 -0000 Received: from niwun.pair.com (HELO localhost) (209.68.2.70) by relay.pair.com with SMTP; 23 Apr 2004 23:34:47 -0000 X-pair-Authenticated: 209.68.2.70 Date: Fri, 23 Apr 2004 18:57:20 -0500 (CDT) From: Mike Silbersack To: jayanth In-Reply-To: <20040423231936.GC21555@yahoo-inc.com> Message-ID: <20040423185501.S5540@odysseus.silby.com> References: <200404231041.i3NAfR7E051507@gw.catspoiler.org> <20040423231936.GC21555@yahoo-inc.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: freebsd-security@FreeBSD.org cc: Don Lewis cc: avalon@caligula.anu.edu.au cc: kernel@yahoo-inc.com Subject: Re: [Full-Disclosure] IETF Draft - Fix for TCP vulnerability (fwd) X-BeenThere: freebsd-security@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Security issues [members-only posting] List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 23 Apr 2004 23:34:48 -0000 On Fri, 23 Apr 2004, jayanth wrote: > > I think Darren's suggestion would be a reasonable compromise; use the > > strict check in the ESTABLISHED state, and the permissive check otherwise. > > Established connections are what would be attacked, so we need the > > security there, but the closing states are where oddities seem to pop up, > > so we can use the permissive check there. > > > > If this is acceptable, I'd like to get it committed this weekend so that > > we can still get it into 4.10. > > > > sure, that sounds reasonable. The sysctl should be good for yahoo. > > thanks, > jayanth There wouldn't be a sysctl, as you wouldn't need one, if I understand things correctly. Since the "bad" RST is in response to the FreeBSD box sending a FIN, the FreeBSD box would have already transitioned to FIN_WAIT_1, and would accept the "bad" RST, as it would only be subject to the check we're using at present. Mike "Silby" Silbersack