From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Lezcano Subject: Re: [PATCH 3/7 net-2.6.25] [IPV4]: Prohibit assignment of 0.0.0.0 as interface address. Date: Fri, 25 Jan 2008 15:37:53 +0100 Message-ID: <4799F441.9050705@fr.ibm.com> References: <1201269123-20378-1-git-send-email-den@openvz.org> <1201269123-20378-3-git-send-email-den@openvz.org> <4799EBBE.6080706@fr.ibm.com> <4799EE8C.60407@sw.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: "Denis V. Lunev" , davem@davemloft.net, netdev@vger.kernel.org, devel@openvz.org, containers@lists.osdl.org To: "Denis V. Lunev" Return-path: Received: from mtagate3.de.ibm.com ([195.212.29.152]:52959 "EHLO mtagate3.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752380AbYAYOlL (ORCPT ); Fri, 25 Jan 2008 09:41:11 -0500 Received: from d12nrmr1607.megacenter.de.ibm.com (d12nrmr1607.megacenter.de.ibm.com [9.149.167.49]) by mtagate3.de.ibm.com (8.13.8/8.13.8) with ESMTP id m0PEfBX1084880 for ; Fri, 25 Jan 2008 14:41:11 GMT Received: from d12av02.megacenter.de.ibm.com (d12av02.megacenter.de.ibm.com [9.149.165.228]) by d12nrmr1607.megacenter.de.ibm.com (8.13.8/8.13.8/NCO v8.7) with ESMTP id m0PEfA5A852176 for ; Fri, 25 Jan 2008 15:41:10 +0100 Received: from d12av02.megacenter.de.ibm.com (loopback [127.0.0.1]) by d12av02.megacenter.de.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id m0PEf9eN008758 for ; Fri, 25 Jan 2008 15:41:10 +0100 In-Reply-To: <4799EE8C.60407@sw.ru> Sender: netdev-owner@vger.kernel.org List-ID: Denis V. Lunev wrote: > Daniel Lezcano wrote: >> Denis V. Lunev wrote: >>> I could hardly imagine why sombady needs to assign 0.0.0.0 as an >>> interface >>> address or interface destination address. The kernel will behave in a >>> strage >>> way in several places if this is possible, as ifa_local != 0 is >>> considered >>> as initialized/non-initialized state of the ifa. >> AFAICS, we should be able to set at an interface address to 0.0.0.0, in >> order to remove an IP address from an interface and keep this one up. >> I see two trivial cases: >> * remove the ipv4 on an interface but continue to use it through ipv6 >> * move ipv4 address from the interface to an attached bridge > > For this case there is an IOCTL/netlink "remove IP address". That's right. But there are people relying on 0.0.0.0 to remove IP addresses, especially in the bridge scripts.