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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 E11E4C433E0 for ; Mon, 8 Jun 2020 18:42:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C57CF2063A for ; Mon, 8 Jun 2020 18:42:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725785AbgFHSmB (ORCPT ); Mon, 8 Jun 2020 14:42:01 -0400 Received: from correo.us.es ([193.147.175.20]:45114 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725280AbgFHSl7 (ORCPT ); Mon, 8 Jun 2020 14:41:59 -0400 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id 82EE9DBC06 for ; Mon, 8 Jun 2020 20:41:56 +0200 (CEST) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 75777DA789 for ; Mon, 8 Jun 2020 20:41:56 +0200 (CEST) Received: by antivirus1-rhel7.int (Postfix, from userid 99) id 6A5D2DA791; Mon, 8 Jun 2020 20:41:56 +0200 (CEST) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 2B288DA78B; Mon, 8 Jun 2020 20:41:54 +0200 (CEST) Received: from 192.168.1.97 (192.168.1.97) by antivirus1-rhel7.int (F-Secure/fsigk_smtp/550/antivirus1-rhel7.int); Mon, 08 Jun 2020 20:41:54 +0200 (CEST) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/antivirus1-rhel7.int) Received: from us.es (unknown [90.77.255.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: 1984lsi) by entrada.int (Postfix) with ESMTPSA id 09FF942EF4E0; Mon, 8 Jun 2020 20:41:53 +0200 (CEST) Date: Mon, 8 Jun 2020 20:41:53 +0200 X-SMTPAUTHUS: auth mail.us.es From: Pablo Neira Ayuso To: Stefano Brivio Cc: Mike Dillinger , stable@vger.kernel.org, netfilter-devel@vger.kernel.org Subject: Re: [PATCH nf] nft_set_rbtree: Don't account for expired elements on insertion Message-ID: <20200608184153.GA7865@salvia> References: <924e80c7b563cc6522a241b123c955c18983edb1.1591141588.git.sbrivio@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <924e80c7b563cc6522a241b123c955c18983edb1.1591141588.git.sbrivio@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Virus-Scanned: ClamAV using ClamSMTP Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Wed, Jun 03, 2020 at 01:50:11AM +0200, Stefano Brivio wrote: > While checking the validity of insertion in __nft_rbtree_insert(), > we currently ignore conflicting elements and intervals only if they > are not active within the next generation. > > However, if we consider expired elements and intervals as > potentially conflicting and overlapping, we'll return error for > entries that should be added instead. This is particularly visible > with garbage collection intervals that are comparable with the > element timeout itself, as reported by Mike Dillinger. > > Other than the simple issue of denying insertion of valid entries, > this might also result in insertion of a single element (opening or > closing) out of a given interval. With single entries (that are > inserted as intervals of size 1), this leads in turn to the creation > of new intervals. For example: > > # nft add element t s { 192.0.2.1 } > # nft list ruleset > [...] > elements = { 192.0.2.1-255.255.255.255 } > > Always ignore expired elements active in the next generation, while > checking for conflicts. > > It might be more convenient to introduce a new macro that covers > both inactive and expired items, as this type of check also appears > quite frequently in other set back-ends. This is however beyond the > scope of this fix and can be deferred to a separate patch. > > Other than the overlap detection cases introduced by commit > 7c84d41416d8 ("netfilter: nft_set_rbtree: Detect partial overlaps > on insertion"), we also have to cover the original conflict check > dealing with conflicts between two intervals of size 1, which was > introduced before support for timeout was introduced. This won't > return an error to the user as -EEXIST is masked by nft if > NLM_F_EXCL is not given, but would result in a silent failure > adding the entry. Applied, thanks.