From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753500Ab2A1CHR (ORCPT ); Fri, 27 Jan 2012 21:07:17 -0500 Received: from shards.monkeyblade.net ([198.137.202.13]:47653 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751339Ab2A1CHQ (ORCPT ); Fri, 27 Jan 2012 21:07:16 -0500 Date: Fri, 27 Jan 2012 21:07:06 -0500 (EST) Message-Id: <20120127.210706.1819458801435039273.davem@davemloft.net> To: ebiederm@xmission.com Cc: eric.dumazet@gmail.com, xemul@parallels.com, sjur.brandeland@stericsson.com, levinsasha928@gmail.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, davej@redhat.com, sjurbren@gmail.com Subject: Re: [PATCH 1/2] netns: Fail conspicously if someone uses net_generic at an inappropriate time. From: David Miller In-Reply-To: References: <20120126.180754.679593869814492219.davem@davemloft.net> X-Mailer: Mew version 6.4 on Emacs 23.3 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.6 (shards.monkeyblade.net [198.137.202.13]); Fri, 27 Jan 2012 18:07:09 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: ebiederm@xmission.com (Eric W. Biederman) Date: Thu, 26 Jan 2012 16:02:55 -0800 > By definition net_generic should never be called when it can return > NULL. Fail conspicously with a BUG_ON to make it clear when people mess > up that a NULL return should never happen. > > Recently there was a bug in the CAIF subsystem where it was registered > with register_pernet_device instead of register_pernet_subsys. It was > erroneously concluded that net_generic could validly return NULL and > that net_assign_generic was buggy (when it was just inefficient). > Hopefully this BUG_ON will prevent people to coming to similar erroneous > conclusions in the futrue. > > Signed-off-by: Eric W. Biederman Applied.