From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: Re: genetlink misinterprets NEW as GET Date: Thu, 06 Jan 2011 15:55:09 +0100 Message-ID: <4D25D7CD.6070006@netfilter.org> References: <4D25C82F.4010306@netfilter.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Netfilter Developer Mailing List , Linux Networking Developer Mailing List To: Jan Engelhardt Return-path: Received: from mail.us.es ([193.147.175.20]:47482 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752915Ab1AFOzN (ORCPT ); Thu, 6 Jan 2011 09:55:13 -0500 In-Reply-To: Sender: netfilter-devel-owner@vger.kernel.org List-ID: On 06/01/11 15:25, Jan Engelhardt wrote: > On Thursday 2011-01-06 14:48, Pablo Neira Ayuso wrote: >>> >>> /* Modifiers to GET request */ >>> #define NLM_F_ROOT 0x100 >>> #define NLM_F_MATCH 0x200 >>> #define NLM_F_ATOMIC 0x400 >>> #define NLM_F_DUMP (NLM_F_ROOT|NLM_F_MATCH) >>> >>> /* Modifiers to NEW request */ >>> #define NLM_F_REPLACE 0x100 >>> #define NLM_F_EXCL 0x200 >>> #define NLM_F_CREATE 0x400 >>> #define NLM_F_APPEND 0x800 >>> >>> Except there is nothing that declares a particular Netlink message >>> as "GET" or "NEW". Subsequently, genetlink chokes: >>> >>> if (nlh->nlmsg_flags & NLM_F_DUMP) >>> if (ops->dumpit == NULL) >>> return -EOPNOTSUPP; >>> >>> Because NLM_F_CREATE | NLM_F_EXCL == NLM_F_DUMP. >>> That, of course, is absolutely bogus. >> >> Hm, NLM_F_CREATE | NLM_F_EXCL is not equal to NLM_F_DUMP. >> >> You must be hitting -EOPNOTSUPP elsewhere. > > No, I am hitting EOPNOTSUPP here; right it's not equal, sorry. > But nlmsg_flags is tested for NLM_F_MATCH (0x200), which is provided by > NLM_F_EXCL. ipset does use NLM_F_EXCL and thus ran into this. i getting confused, so ipset is also setting NLM_F_REPLACE to match the NLM_F_DUMP bitmask?