From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 26B9FC433EF for ; Fri, 15 Oct 2021 11:25:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0BE9C610E8 for ; Fri, 15 Oct 2021 11:25:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234139AbhJOL1l (ORCPT ); Fri, 15 Oct 2021 07:27:41 -0400 Received: from mail.netfilter.org ([217.70.188.207]:48672 "EHLO mail.netfilter.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234195AbhJOL1l (ORCPT ); Fri, 15 Oct 2021 07:27:41 -0400 Received: from netfilter.org (unknown [78.30.32.163]) by mail.netfilter.org (Postfix) with ESMTPSA id 7CE0A60098; Fri, 15 Oct 2021 13:23:54 +0200 (CEST) Date: Fri, 15 Oct 2021 13:25:29 +0200 From: Pablo Neira Ayuso To: Phil Sutter , netfilter-devel@vger.kernel.org Subject: Re: [iptables PATCH v2 00/17] Eliminate dedicated arptables-nft parser Message-ID: References: <20210930140419.6170-1-phil@nwl.cc> <20211015110124.GL1668@orbyte.nwl.cc> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20211015110124.GL1668@orbyte.nwl.cc> Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org On Fri, Oct 15, 2021 at 01:01:24PM +0200, Phil Sutter wrote: > Hi Pablo, > > On Thu, Oct 14, 2021 at 10:56:09PM +0200, Pablo Neira Ayuso wrote: > > On Thu, Sep 30, 2021 at 04:04:02PM +0200, Phil Sutter wrote: > > > Commandline parsing was widely identical with iptables and ip6tables. > > > This series adds the necessary code-changes to unify the parsers into a > > > common one. > > > > > > Changes since v1: > > > - Fix patch 12, the parser has to check existence of proto_parse > > > callback before dereferencing it. Otherwise arptables-nft segfaults if > > > '-p' option is given. > > > > LGTM. > > Thanks for your review! > > > > - Patches 13-17 add all the arptables quirks to restore compatibility > > > with arptables-legacy. I didn't consider them important enough to push > > > them unless someone complains. Yet breaking existing scripts is bad > > > indeed. Please consider them RFC: If you consider (one of) them not > > > important, please NACk and I will drop them before pushing. > > > > For patch 13-16, you could display a warning for people to fix their > > scripts, so this particular (strange) behaviour in some cases can be > > dropped (at least, 13-15 look like left-over/bugs). For the > > check_inverse logic, I'd suggest to display a warning too, this is > > what it was done in iptables time ago to address this inconsistency. > > I wonder how likely it is for someone to rely upon the behaviour. I can > imagine a script passing an empty interface name and expecting the > argument to be ignored (patch 13). Though what are the odds someone > actually calls arptables with '-m something' (patch 14) or a bogus table > name (patch 15)? I think this is a leftover/bug that has been there for long time. > > I'd probably keep back patch 17/17, the max chain name length was > > reduced by when the revision field was introduced and this resulted in > > no issue being reported. > > If that's OK with you, I would turn the empty interface name error into > a warning for arptables-nft, reintroduce the warning for intrapositioned > negations and drop the remaining quirks as they are likely hiding a bug. Agreed.