From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] Fix corrupt TCP packets when options space overflows with MD5SIG enabled Date: Sun, 01 Jun 2008 23:56:49 -0700 (PDT) Message-ID: <20080601.235649.109450540.davem@davemloft.net> References: <396556a20805301140x586093e5o92d44e38f7c2869a@mail.gmail.com> <396556a20805301217k293e5718h6bbf02bfe0683143@europa> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: agl@imperialviolet.org, netdev@vger.kernel.org To: jmorris@namei.org Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:41704 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752566AbYFBG4w (ORCPT ); Mon, 2 Jun 2008 02:56:52 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: From: James Morris Date: Mon, 2 Jun 2008 09:40:15 +1000 (EST) > On Sat, 31 May 2008, Adam Langley wrote: > > > When MD5 signatures are turned on we can end up with syntactically invalid > > packets with a header length < 20 bytes. This is because tcp_header_size > > overflows with 12 bytes of timestamp, 20 bytes of signature and > 8 bytes of > > SACK option. > > > > Since we can't fit any SACK blocks in the final 8 bytes of options space, and > > the MD5 signature is more important, we disable including SACK, or even > > advertising it, when MD5 is enabled. > > > > Signed-off-by: Adam Langley > > Reviewed-by: James Morris After making some minor coding style fixups, I applied this fix, thanks everyone.