From mboxrd@z Thu Jan 1 00:00:00 1970 From: Amir Vadai Subject: Re: [PATCH net-next 3/3] net/sched: Introduce act_iptunnel Date: Tue, 23 Aug 2016 19:05:37 +0300 Message-ID: <20160823160537.GB12627@office.localdomain> References: <20160822143834.32422-1-amir@vadai.me> <20160822143834.32422-4-amir@vadai.me> <20160822205137.30cda14f@griffin> <20160823152805.GA12627@office.localdomain> <20160823173349.2b64b466@griffin> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Or Gerlitz , "David S. Miller" , Linux Netdev List , John Fastabend , Jiri Pirko , Cong Wang , Jamal Hadi Salim , Or Gerlitz , Hadar Har-Zion To: Jiri Benc Return-path: Received: from mail-wm0-f65.google.com ([74.125.82.65]:34236 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752134AbcHWQYl (ORCPT ); Tue, 23 Aug 2016 12:24:41 -0400 Received: by mail-wm0-f65.google.com with SMTP id q128so18810601wma.1 for ; Tue, 23 Aug 2016 09:22:54 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20160823173349.2b64b466@griffin> Sender: netdev-owner@vger.kernel.org List-ID: On Tue, Aug 23, 2016 at 05:33:49PM +0200, Jiri Benc wrote: > On Tue, 23 Aug 2016 18:28:05 +0300, Amir Vadai wrote: > > On Mon, Aug 22, 2016 at 08:51:37PM +0200, Jiri Benc wrote: > > > 2. We may run into problems like tx path seeing the metadata_dst that > > > it should not see. This means either this situation or such > > > configuration must be prevented somehow. > [...] > > Anyway, this issue is orthogonal to this patchset... > > Not really. If it's indeed (2) then such configuration needs to be > rejected. The configuration that needs to be rejected is when act_iptunnel is not used. So, I guess the fix won't be part of it... > Or metadata_dst freed at an appropriate place. Thus it's > something that needs to be handled by this patchset before the uAPI is > set in stone. It is already there - user can use act_mirred and redirect skb's with metadata since shared tunnel devices introduced. The only thing that was added here, is to enable the user to drop the metadata, which I think we agree is the ok. But I agree with you, that I must understand the life cycle of the metadata and dst better. I will try to understand it better and explain/fix accordingly. Again, would be happy if someone will chime in and give some hints if it was a bug, that a user could redirect skb's with metadata, or something harmless. Thanks, Amir > > Jiri