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,URIBL_BLOCKED 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 EAB61C43331 for ; Fri, 3 Apr 2020 14:12:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B2C152077D for ; Fri, 3 Apr 2020 14:12:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="I+tokmwq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728216AbgDCOM0 (ORCPT ); Fri, 3 Apr 2020 10:12:26 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:37796 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727431AbgDCOM0 (ORCPT ); Fri, 3 Apr 2020 10:12:26 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1585923144; 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=JysG2Cfhvfh0JctcYoKMUX09HxGB/ZU0fO72eGyNkFY=; b=I+tokmwqtewxlpcSAt1zo4kcz90gbPDE2sbtQwclwQIMrYbAhRZLrdegROj8hXoNIRYAnS US4Vca8PglDmdtl6bYfb7aeTFmELSTrEz9VAIhFkUz88bX+Bts8bjppYASj04GM3BTZlFu xrrwVVqEM3MwthM4BhPKqhCeDvmBwPY= 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-200-gfPedJH-OIyvwaukLjf2FA-1; Fri, 03 Apr 2020 10:12:10 -0400 X-MC-Unique: gfPedJH-OIyvwaukLjf2FA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 49FEC18A6EC1; Fri, 3 Apr 2020 14:12:09 +0000 (UTC) Received: from elisabeth (unknown [10.36.110.17]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E88E319756; Fri, 3 Apr 2020 14:12:07 +0000 (UTC) Date: Fri, 3 Apr 2020 16:12:02 +0200 From: Stefano Brivio To: Pablo Neira Ayuso Cc: netfilter-devel@vger.kernel.org, fw@strlen.de Subject: Re: [PATCH] segtree: bail out on concatenations Message-ID: <20200403161202.4d1b2322@elisabeth> In-Reply-To: <20200403153331.53e1bbec@elisabeth> References: <20200402214941.60097-1-pablo@netfilter.org> <20200403120351.cxhcdcwfpylven4k@salvia> <20200403142705.59f2e7d7@elisabeth> <20200403125029.pb2emvu24aspprw5@salvia> <20200403153331.53e1bbec@elisabeth> Organization: Red Hat MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org On Fri, 3 Apr 2020 15:33:31 +0200 Stefano Brivio wrote: > On Fri, 3 Apr 2020 14:50:29 +0200 > Pablo Neira Ayuso wrote: > > > On Fri, Apr 03, 2020 at 02:27:05PM +0200, Stefano Brivio wrote: > > > On Fri, 3 Apr 2020 14:03:51 +0200 > > > Pablo Neira Ayuso wrote: > > > > > > > On Thu, Apr 02, 2020 at 11:49:41PM +0200, Pablo Neira Ayuso wrote: > > > > > This patch adds a lazy check to validate that the first element is not a > > > > > concatenation. The segtree code does not support for concatenations, > > > > > bail out with EOPNOTSUPP. > > > > > > > > > > # nft add element x y { 10.0.0.0/8 . 192.168.1.3-192.168.1.9 . 1024-65535 } > > > > > Error: Could not process rule: Operation not supported > > > > > add element x y { 10.0.0.0/8 . 192.168.1.3-192.168.1.9 . 1024-65535 } > > > > > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > > > > > > > > > Otherwise, the segtree code barfs with: > > > > > > > > > > BUG: invalid range expression type concat > > > > > > > > Hm. > > > > > > > > I'm afraid this patch is not enough, the following ruleset crashes > > > > in old kernels with recent nft: > > > > > > > > flush ruleset > > > > > > > > table inet filter { > > > > set test { > > > > type ipv4_addr . ipv4_addr . inet_service > > > > flags interval,timeout > > > > elements = { 1.1.1.1 . 2.2.2.2 . 30 , > > > > 2.2.2.2 . 3.3.3.3 . 40 , > > > > 3.3.3.3 . 4.4.4.4 . 50 } > > > > } > > > > > > > > chain output { > > > > type filter hook output priority 0; policy accept; > > > > ip saddr . ip daddr . tcp dport @test counter > > > > } > > > > } > > > > > > First off, sorry, it didn't occur to me to run new tests on older > > > kernels. :/ > > > > > > I can't quickly run that on some older kernel right now. For my > > > understanding, where is it crashing? > > > > When listing via > > > > nft list ruleset > > > > The segtree does not know how to handle this concatenation. > > Ouch, I see. > > > The only way I found to prevent this error is to bail out when adding > > the set, ie. old kernel checks that NFT_SET_CONCAT is not supported, > > hence it bails out. > > Right, it took me a while to realise you're referring to the flag that > was present until v2 and I dropped in v3 (gold medal goes to truly > yours -- I actually proposed that :/). > > > I'm going to prepare patches to submit this to nf.git. > > I'm still wondering if we can come up with a userspace-only fix by > understanding kernel support level somehow (not via flags) and refuse > to add that type of set. I'm still checking. Nope, sorry, I can't think of anything better than what you already proposed. -- Stefano