From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: FYI: tftp-hpa breaks when used on secondary ip addresses Date: Fri, 04 Mar 2011 20:58:17 -0800 (PST) Message-ID: <20110304.205817.193701195.davem@davemloft.net> References: <4D719254.8000903@zytor.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: ebiederm@xmission.com, netdev@vger.kernel.org, jsing@google.com To: hpa@zytor.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:48731 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752444Ab1CEE5l (ORCPT ); Fri, 4 Mar 2011 23:57:41 -0500 In-Reply-To: <4D719254.8000903@zytor.com> Sender: netdev-owner@vger.kernel.org List-ID: From: "H. Peter Anvin" Date: Fri, 04 Mar 2011 17:31:00 -0800 > If this is done for all local connections (as opposed to the ones that > have been configured explicitly by the administrator to behave that > way), that's a massive lossage. Not only does a large number of > applications use this trick to determine if an address is local (e.g. > allowing bypass) -- it is pretty much the only portable way to do it -- > but it would cause applications which expect to get a reply back from > the same address they sent a request to to completely fall on their face. Actually this is what SOL_IP, IP_PKTINFO, was created for. Even glibc uses it.