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=-5.3 required=3.0 tests=BAYES_00, 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 F411FC433DB for ; Thu, 18 Feb 2021 14:57:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9FC1864EAD for ; Thu, 18 Feb 2021 14:57:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230305AbhBRO5O (ORCPT ); Thu, 18 Feb 2021 09:57:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53700 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232851AbhBRMyQ (ORCPT ); Thu, 18 Feb 2021 07:54:16 -0500 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [IPv6:2a0a:51c0:0:12e:520::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C760AC061788; Thu, 18 Feb 2021 04:52:50 -0800 (PST) Received: from fw by Chamillionaire.breakpoint.cc with local (Exim 4.92) (envelope-from ) id 1lCinY-0006mx-FH; Thu, 18 Feb 2021 13:52:48 +0100 Date: Thu, 18 Feb 2021 13:52:48 +0100 From: Florian Westphal To: Richard Guy Briggs Cc: Florian Westphal , Phil Sutter , LKML , Linux-Audit Mailing List , netfilter-devel@vger.kernel.org, twoerner@redhat.com, Eric Paris , tgraf@infradead.org Subject: Re: [PATCH ghak124 v3] audit: log nftables configuration change events Message-ID: <20210218125248.GB22944@breakpoint.cc> References: <20210211151606.GX3158@orbyte.nwl.cc> <20210211202628.GP2015948@madcap2.tricolour.ca> <20210211220930.GC2766@breakpoint.cc> <20210217234131.GN3141668@madcap2.tricolour.ca> <20210218082207.GJ2766@breakpoint.cc> <20210218124211.GO3141668@madcap2.tricolour.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210218124211.GO3141668@madcap2.tricolour.ca> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Richard Guy Briggs wrote: > On 2021-02-18 09:22, Florian Westphal wrote: > > No. There is a hierarchy, e.g. you can't add a chain without first > > adding a table, BUT in case the table was already created by an earlier > > transaction it can also be stand-alone. > > Ok, so there could be a stand-alone chain mod with one table, then a > table add of a different one with a "higher ranking" op... Yes, that can happen. > > > It seems I'd need to filter out the NFT_MSG_GET_* ops. > > > > No need, the GET ops do not cause changes and will not trigger a > > generation id change. > > Ah, so it could trigger on generation change. Would GET ops be included > in any other change No, GET ops are standalone, they cannot be part of a transaction. If you look at static const struct nfnl_callback nf_tables_cb[NFT_MSG_MAX] = { array in nf_tables_api.c, then those ops with a '.call_batch' can appear in transaction (i.e., can cause modification). The other ones (.call_rcu) are read-only. If they appear in a batch tehy will be ignored, if the batch consists of such non-modifying ops only then nf_tables_commit() returns early because the transaction list is empty (nothing to do/change). > such that it would be desirable to filter them out > to reduce noise in that single log line if it is attempted to list all > the change ops? It almost sounds like it would be better to do one > audit log line for each table for each family, and possibly for each op > to avoid the need to change userspace. This would already be a > significant improvement picking the highest ranking op. I think i understand what you'd like to do. Yes, that would reduce the log output a lot.