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 7EE2AC433EF for ; Fri, 15 Oct 2021 11:01:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 539FD61073 for ; Fri, 15 Oct 2021 11:01:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238213AbhJOLDg (ORCPT ); Fri, 15 Oct 2021 07:03:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35320 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235080AbhJOLDf (ORCPT ); Fri, 15 Oct 2021 07:03:35 -0400 Received: from orbyte.nwl.cc (orbyte.nwl.cc [IPv6:2001:41d0:e:133a::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 38FD5C061570 for ; Fri, 15 Oct 2021 04:01:29 -0700 (PDT) Received: from n0-1 by orbyte.nwl.cc with local (Exim 4.94.2) (envelope-from ) id 1mbKxo-0001il-Dg; Fri, 15 Oct 2021 13:01:24 +0200 Date: Fri, 15 Oct 2021 13:01:24 +0200 From: Phil Sutter To: Pablo Neira Ayuso Cc: netfilter-devel@vger.kernel.org Subject: Re: [iptables PATCH v2 00/17] Eliminate dedicated arptables-nft parser Message-ID: <20211015110124.GL1668@orbyte.nwl.cc> Mail-Followup-To: Phil Sutter , Pablo Neira Ayuso , netfilter-devel@vger.kernel.org References: <20210930140419.6170-1-phil@nwl.cc> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org 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'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. Cheers, Phil