From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick McHardy Subject: Re: [PATCH 02/13] IP set core support Date: Wed, 02 Feb 2011 07:50:46 +0100 Message-ID: <4D48FEC6.5080701@trash.net> References: <1296514388-20900-1-git-send-email-kadlec@blackhole.kfki.hu> <1296514388-20900-2-git-send-email-kadlec@blackhole.kfki.hu> <1296514388-20900-3-git-send-email-kadlec@blackhole.kfki.hu> <4D482817.7090407@trash.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Cc: netfilter-devel@vger.kernel.org, Pablo Neira Ayuso To: Jozsef Kadlecsik Return-path: Received: from stinky.trash.net ([213.144.137.162]:61115 "EHLO stinky.trash.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752062Ab1BBGvA (ORCPT ); Wed, 2 Feb 2011 01:51:00 -0500 In-Reply-To: Sender: netfilter-devel-owner@vger.kernel.org List-ID: On 01.02.2011 22:28, Jozsef Kadlecsik wrote: > On Tue, 1 Feb 2011, Jozsef Kadlecsik wrote: > >>>> I guess you're relying on that the original message is appended to a >>>> nlmsgerr message. That doesn't seem right though, if you want to return >>>> something to userspace, you should construct a new message. >>> >>> The message we are processing here carried multiple commands (each having >>> an attribute with the line number of the given command) and one failed >>> from some reason. We have to notify the userspace which command, at what >>> line failed. For this reason the multi-command messages have got an >>> attribute, which can be filled out with the line number - that happens >>> here. The attribute is already there, the message is not enlarged, just >>> the empty value is overwritten with the proper value. >>> >>> The line number reporting works this way, tested in the testsuite too. >>> >>> If I had to construct a completely new message and sent it, that'd be more >>> or less the duplication of netlink_ack. Additionally I had to suppress >>> netlink from sending an errmsg/ack too. >> >> Hm, if I lie -EINTR to netlink, then I can construct and send the error >> message manually and keep NLM_F_ACK at the same time. What do you think? >> Please have a look at the attached patch. > > Oops, mistypeing fixed, here follow the hopefully good version. This looks fine to me. A comment about why it returns -EINTR would probably be a good idea though.