From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net] ip_tunnel: Don't allow to add the same tunnel multiple times. Date: Fri, 26 Sep 2014 00:43:00 -0400 (EDT) Message-ID: <20140926.004300.883593012234297777.davem@davemloft.net> References: <20140922071108.GY6390@secunet.com> <20140922.164556.736459936247558402.davem@davemloft.net> <20140923113051.GZ6390@secunet.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: steffen.klassert@secunet.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:37773 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751982AbaIZEnC (ORCPT ); Fri, 26 Sep 2014 00:43:02 -0400 In-Reply-To: <20140923113051.GZ6390@secunet.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Steffen Klassert Date: Tue, 23 Sep 2014 13:30:51 +0200 > On Mon, Sep 22, 2014 at 04:45:56PM -0400, David Miller wrote: >> From: Steffen Klassert >> Date: Mon, 22 Sep 2014 09:11:08 +0200 >> >> > When we try to add an already existing tunnel, we don't return >> > an error. Instead we continue and call ip_tunnel_update(). >> > This means that we can change existing tunnels by adding >> > the same tunnel multiple times. It is even possible to change >> > the tunnel endpoints of the fallback device. >> > >> > We fix this by returning an error if we try to add an existing >> > tunnel. >> > >> > Signed-off-by: Steffen Klassert >> > --- >> > >> > I was not able to find a commit that introduced this bug. >> > Looks like ipip and ip_gre had similar bugs already with >> > the initial git commit. >> >> I'm not so sure about this, perhaps the behavior of being able to >> change a configuration using an ADD call is intentional? > > Hm, I don't think so. Initially it was the same like with ipv6. > It was possible to add the same tunnel muliple times without > getting an error, no config change was made. The possibilty > to change the configuration by adding the same tunnel a second > time came with the tunnel code unification. Ok, makes sense. Applied, thanks Steffen. If I had a euro for every regression introduced by that tunnel unification patch set I'd be a rich man indeed :-/