From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from ganesha.gnumonks.org (ganesha.gnumonks.org [213.95.27.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0A2377995B; Fri, 2 Feb 2024 11:12:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.95.27.120 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706872334; cv=none; b=g4jebpIDiTesX5rWO1Ceusr05bHP79DyYkzEt0O2SLsnfE4/4ue2oA3G4TRquBjLum/vgyGUm9I5eYgiJU5/US6T207qau/vmL2o4QnsuHlfV3uae8rKqj9Fw9y3dYAqYkh9POVECJQiuA0DsmkaI6Rp4gPw4EsKAMx0hYFoMYc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706872334; c=relaxed/simple; bh=DHXhgGTeA1+lWgExd1fQrxzIbyU8ibghu/opgphfpvw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=McXv43nvkVBBWLqjQ5K5q/VBUuVOCIeMVmCrqMlQGLsHNWbzHRgV6tQV+lBbKkfSkvgw+6aWBl4ORJCUqYgus9gQkOMNDpJALKkVvYs6zMNiIzUnjjjs0Y6DqhuGjT0wXBP0CiYIMmgcRypunOlp8dVbzza/BclpFEUk3SnBDzg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org; spf=pass smtp.mailfrom=gnumonks.org; arc=none smtp.client-ip=213.95.27.120 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gnumonks.org Received: from [78.30.41.52] (port=57718 helo=gnumonks.org) by ganesha.gnumonks.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1rVrSm-001lhN-5h; Fri, 02 Feb 2024 12:12:06 +0100 Date: Fri, 2 Feb 2024 12:12:03 +0100 From: Pablo Neira Ayuso To: Ilya Maximets Cc: Felix Huettner , linux-kernel@vger.kernel.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, kadlec@netfilter.org, fw@strlen.de, davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, shuah@kernel.org, luca.czesla@mail.schwarz, max.lamprecht@mail.schwarz, Simon Horman Subject: Re: [PATCH net-next v2] net: ctnetlink: support filtering by zone Message-ID: References: <2032238f-31ac-4106-8f22-522e76df5a12@ovn.org> Precedence: bulk X-Mailing-List: netfilter-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <2032238f-31ac-4106-8f22-522e76df5a12@ovn.org> X-Spam-Score: -1.8 (-) On Fri, Feb 02, 2024 at 12:04:35PM +0100, Ilya Maximets wrote: > On 12/22/23 13:01, Pablo Neira Ayuso wrote: > > On Mon, Nov 27, 2023 at 11:49:16AM +0000, Felix Huettner wrote: > >> conntrack zones are heavily used by tools like openvswitch to run > >> multiple virtual "routers" on a single machine. In this context each > >> conntrack zone matches to a single router, thereby preventing > >> overlapping IPs from becoming issues. > >> In these systems it is common to operate on all conntrack entries of a > >> given zone, e.g. to delete them when a router is deleted. Previously this > >> required these tools to dump the full conntrack table and filter out the > >> relevant entries in userspace potentially causing performance issues. > >> > >> To do this we reuse the existing CTA_ZONE attribute. This was previous > >> parsed but not used during dump and flush requests. Now if CTA_ZONE is > >> set we filter these operations based on the provided zone. > >> However this means that users that previously passed CTA_ZONE will > >> experience a difference in functionality. > >> > >> Alternatively CTA_FILTER could have been used for the same > >> functionality. However it is not yet supported during flush requests and > >> is only available when using AF_INET or AF_INET6. > > > > For the record, this is applied to nf-next. > > Hi, Felix and Pablo. > > I was looking through the code and the following part is bothering me: > > diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c > index fb0ae15e96df..4e9133f61251 100644 > --- a/net/netfilter/nf_conntrack_netlink.c > +++ b/net/netfilter/nf_conntrack_netlink.c > @@ -1148,6 +1149,10 @@ static int ctnetlink_filter_match(struct nf_conn *ct, void *data) > if (filter->family && nf_ct_l3num(ct) != filter->family) > goto ignore_entry; > > + if (filter->zone.id != NF_CT_DEFAULT_ZONE_ID && > + !nf_ct_zone_equal_any(ct, &filter->zone)) > + goto ignore_entry; > + > if (filter->orig_flags) { > tuple = nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL); > if (!ctnetlink_filter_match_tuple(&filter->orig, tuple, > > If I'm reading that right, the default zone is always flushed, even if the > user requested to flush a different zone. I.e. the entry is never ignored > for a default zone. Is that correct or am I reading that wrong? > > If my observation is correct, then I don't think this functionality can > actually be used by applications as it does something unexpected. This needs a fix, the NF_CT_DEFAULT_ZONE_ID is used as a marker to indicate if the filtering by zone needs to happen or not. I'd suggest to add a boolean flag that specifies that zone filtering is set on.