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 5535EC2BA83 for ; Fri, 14 Feb 2020 17:35:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3A3A92082F for ; Fri, 14 Feb 2020 17:35:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391117AbgBNRez (ORCPT ); Fri, 14 Feb 2020 12:34:55 -0500 Received: from orbyte.nwl.cc ([151.80.46.58]:40784 "EHLO orbyte.nwl.cc" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390318AbgBNRev (ORCPT ); Fri, 14 Feb 2020 12:34:51 -0500 Received: from n0-1 by orbyte.nwl.cc with local (Exim 4.91) (envelope-from ) id 1j2era-0004f0-45; Fri, 14 Feb 2020 18:34:50 +0100 Date: Fri, 14 Feb 2020 18:34:50 +0100 From: Phil Sutter To: Pablo Neira Ayuso Cc: netfilter-devel@vger.kernel.org Subject: Re: [libnftnl PATCH] src: Fix nftnl_assert() on data_len Message-ID: <20200214173450.GR20005@orbyte.nwl.cc> Mail-Followup-To: Phil Sutter , Pablo Neira Ayuso , netfilter-devel@vger.kernel.org References: <20200214172417.11217-1-phil@nwl.cc> <20200214173247.2wbrvcqilqfmcqq5@salvia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200214173247.2wbrvcqilqfmcqq5@salvia> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org On Fri, Feb 14, 2020 at 06:32:47PM +0100, Pablo Neira Ayuso wrote: > On Fri, Feb 14, 2020 at 06:24:17PM +0100, Phil Sutter wrote: > > Typical idiom for *_get_u*() getters is to call *_get_data() and make > > sure data_len matches what each of them is returning. Yet they shouldn't > > trust *_get_data() to write into passed pointer to data_len since for > > chains and NFTNL_CHAIN_DEVICES attribute, it does not. Make sure these > > assert() calls trigger in those cases. > > The intention to catch for unset attributes through the assertion, > right? No, this is about making sure that no wrong getter is called, e.g. nftnl_chain_get_u64() with e.g. NFTNL_CHAIN_HOOKNUM attribute which is only 32bits. Cheers, Phil