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 X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0AB15C4BA0E for ; Wed, 26 Feb 2020 11:03:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CF8B324684 for ; Wed, 26 Feb 2020 11:03:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="AFG5lFE6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728014AbgBZLDH (ORCPT ); Wed, 26 Feb 2020 06:03:07 -0500 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:42694 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727362AbgBZLDH (ORCPT ); Wed, 26 Feb 2020 06:03:07 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1582714986; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4yISX8OrkxfmsmeY3SzFIS/Eqjq+YoJCosZCI/7ItrU=; b=AFG5lFE6gvaQO0dVlpuPNO7u6jzgWPU4G5TYdOljRkwWvFDeIE9o+AybA1kGtqfoV0z3xR kEsFKPVfLNZktNwXU5RJGC993AM/E6pMYbIpK3Ji2xpi7tg3JwjLa1dz+DQE+fRluCgsxU lwLEiNukE2+XSNkGfMhGtQJTlEOnWM4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-304-TAKt7iWgM_GBsf-I0nFQOw-1; Wed, 26 Feb 2020 06:03:02 -0500 X-MC-Unique: TAKt7iWgM_GBsf-I0nFQOw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2607B13E2; Wed, 26 Feb 2020 11:03:01 +0000 (UTC) Received: from localhost (ovpn-200-34.brq.redhat.com [10.40.200.34]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 819E060BE1; Wed, 26 Feb 2020 11:02:59 +0000 (UTC) Date: Wed, 26 Feb 2020 12:02:53 +0100 From: Stefano Brivio To: Pablo Neira Ayuso Cc: Phil Sutter , netfilter-devel@vger.kernel.org, Florian Westphal Subject: Re: [PATCH nf 0/2] nft_set_pipapo: Fix crash due to dangling entries in mapping table Message-ID: <20200226120253.71e9f0e0@redhat.com> In-Reply-To: <20200226105804.xramr6duqkvrtop3@salvia> References: <20200221232218.2157d72b@elisabeth> <20200222011933.GO20005@orbyte.nwl.cc> <20200223222258.2bb7516a@redhat.com> <20200225123934.p3vru3tmbsjj2o7y@salvia> <20200225141346.7406e06b@redhat.com> <20200225134236.sdz5ujufvxm2in3h@salvia> <20200225153435.17319874@redhat.com> <20200225202143.tqsfhggvklvhnsvs@salvia> <20200225213815.3c0a1caa@redhat.com> <20200225205847.s5pjjp652unj6u7v@salvia> <20200226105804.xramr6duqkvrtop3@salvia> Organization: Red Hat MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org On Wed, 26 Feb 2020 11:58:04 +0100 Pablo Neira Ayuso wrote: > On Tue, Feb 25, 2020 at 09:58:47PM +0100, Pablo Neira Ayuso wrote: > > On Tue, Feb 25, 2020 at 09:38:15PM +0100, Stefano Brivio wrote: > > > On Tue, 25 Feb 2020 21:21:43 +0100 > > > Pablo Neira Ayuso wrote: > > > > > > > Hi Stefano, > > > > > > > > On Tue, Feb 25, 2020 at 03:34:35PM +0100, Stefano Brivio wrote: > > > > [...] > > > > > This is the problem Phil reported: > > > > [...] > > > > > Or also simply with: > > > > > > > > > > # nft add element t s '{ 20-30 . 40 }' > > > > > # nft add element t s '{ 25-35 . 40 }' > > > > > > > > > > the second element is silently ignored. I'm returning -EEXIST from > > > > > nft_pipapo_insert(), but nft_add_set_elem() clears it because NLM_F_EXCL > > > > > is not set. > > > > > > > > > > Are you suggesting that this is consistent and therefore not a problem? > > > > > > > > NLM_F_EXCL !NLM_F_EXCL > > > > exact match EEXIST 0 [*] > > > > partial match EEXIST EEXIST > > > > > > > > The [*] case would allow for element timeout/expiration updates from > > > > the control plane for exact matches. > > > > > > A-ha. I didn't even consider that. > > > > > > > Note that element updates are not > > > > supported yet, so this check for !NLM_F_EXCL is a stub. I don't think > > > > we should allow for updates on partial matches > > > > > > > > I think what it is missing is a error to report "partial match" from > > > > pipapo. Then, the core translates this "partial match" error to EEXIST > > > > whether NLM_F_EXCL is set or not. > > > > > > Yes, given what you explained, I also think it's the case. > > > > > > > Would this work for you? > > > > > > It would. I need to write a few more lines in nft_pipapo_insert(), > > > because right now I don't have a special case for "entirely > > > overlapping". Something on the lines of: > > > > > > dup = pipapo_get(net, set, start, genmask); > > > if (PTR_ERR(dup) == -ENOENT) { > > > > > > --> compare start and end key for this entry with > > > start and end key from 'ext' > > > > > > Let me know if you want me to post a patch with a placeholder for > > > whatever you have in mind, or if I can help implementing this, etc. > > > > Please, go ahead with the placeholder, it might be faster. I'll jump > > on it. > > Sorry, I just realized I can be probably quicker on the core side. > Here is my proposal. > > I'm attaching a patch for the core. This is handling -ENOTEMPTY which > is (ab)used to report the partial element matching. > > if NLM_F_EXCL is set off, then -EEXIST becomes 0. > then -ENOTEMPTY becomes -EEXIST. > > Would this work for you? Oops, I sent you my patch 80 seconds later it seems. Yes, we just need to s/TTY/TEMPTY/ :) Let me know how to proceed, if you want me to post that or you want to post that (as a series?). -- Stefano