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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E2D63C7619A for ; Wed, 12 Apr 2023 19:37:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229651AbjDLThW (ORCPT ); Wed, 12 Apr 2023 15:37:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58250 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229520AbjDLThV (ORCPT ); Wed, 12 Apr 2023 15:37:21 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CA8E62136; Wed, 12 Apr 2023 12:37:20 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 61EFB62C91; Wed, 12 Apr 2023 19:37:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 74BF7C433EF; Wed, 12 Apr 2023 19:37:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1681328239; bh=YdA6xgVDMTsi6jbxImRni18coXjbrnh0VRM9FC3CJx4=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Pi1onOod7InvwJqqgwwAKKZgJBiNDRm4johlj/xBBOXnxKqrXyYFdGP7ejq1cA+h7 hUkrZCn/PtOcwDGFNbcWKLAxGJf24d3BH63jPUIG9EDWLn9J4piTeZEXbe5V2EoI4a vv4qDBVOR1GhvqA5rA0SI6Ooh4Gd0K8lgckdi39g5xKZWL7cDkrGfqTj6IwtxA/mYx e7w/YamddrbpJzOpECn2e8nUVKBHYspjWKZDdZw1RMTTUDZQQ1D5UtL8l5d1d2gZuM QnStOpq4LHuK8GPPeXkwaiWeTfq9ErdzEHMXBUuX00vZNW5rsmpNGzNd6qSU0f3eZE Do1F8dNutgSiw== Date: Wed, 12 Apr 2023 12:37:18 -0700 From: Jakub Kicinski To: Matthieu Baerts Cc: Pablo Neira Ayuso , netfilter-devel@vger.kernel.org, davem@davemloft.net, netdev@vger.kernel.org, pabeni@redhat.com, edumazet@google.com, mathew.j.martineau@linux.intel.com, mptcp@lists.linux.dev Subject: Re: [PATCH net,v2] uapi: linux: restore IPPROTO_MAX to 256 and add IPPROTO_UAPI_MAX Message-ID: <20230412123718.7e6c0b55@kernel.org> In-Reply-To: <7405c14e-1fbe-c820-c470-36b0a50b4cae@tessares.net> References: <20230406092558.459491-1-pablo@netfilter.org> <20230412072104.61910016@kernel.org> <405a8fa2-4a71-71c8-7715-10d3d2301dac@tessares.net> <7405c14e-1fbe-c820-c470-36b0a50b4cae@tessares.net> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, 12 Apr 2023 18:35:40 +0200 Matthieu Baerts wrote: > > Is this theoretical, or you think any library might be doing this > > already? I lack of sufficient knowledge of the MPTCP ecosystem to > > evaluate myself. > > This is theoretical. > > But using it with socket's protocol parameter is the only good usage of > IPPROTO_MAX for me :-D Perhaps. No strong preference from me. That said I think I can come up with a good name for the SO use: SO_IPPROTO_MAX (which IMHO it's better than IPPROTO_UAPI_MAX if Pablo doesn't mind sed'ing?) The name for a max in proto sense... I'm not sure what that would be. IPPROTO_MAX_IPPROTO ? IP_IPROTO_MAX ? IP_PROTO_MAX ? Dunno.. > More seriously, I don't see such things when looking at: > > > https://codesearch.debian.net/search?q=%5CbIPPROTO_MAX%5Cb&literal=0&perpkg=1 > > IPPROTO_MAX is (re)defined in different libs but not used in many > programs, mainly in Netfilter related programs in fact. > > > Even if it is linked to MPTCP, I cannot judge if it can be an issue or > not because it depends on how the different libC or other libs/apps are > interpreting this IPPROTO_MAX and if they are using it before creating a > socket.