From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750917AbXCGL7s (ORCPT ); Wed, 7 Mar 2007 06:59:48 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751109AbXCGL7r (ORCPT ); Wed, 7 Mar 2007 06:59:47 -0500 Received: from relay.2ka.mipt.ru ([194.85.82.65]:35859 "EHLO 2ka.mipt.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750917AbXCGL7r (ORCPT ); Wed, 7 Mar 2007 06:59:47 -0500 Date: Wed, 7 Mar 2007 14:59:14 +0300 From: Evgeniy Polyakov To: Philipp Reisner Cc: linux-kernel@vger.kernel.org, drbd-dev@linbit.com Subject: Re: connector: Bugfix for cn_call_callback() Message-ID: <20070307115914.GA1287@2ka.mipt.ru> References: <200703071226.13088.philipp.reisner@linbit.com> Mime-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Disposition: inline In-Reply-To: <200703071226.13088.philipp.reisner@linbit.com> User-Agent: Mutt/1.5.9i X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-3.0 (2ka.mipt.ru [0.0.0.0]); Wed, 07 Mar 2007 14:59:18 +0300 (MSK) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 07, 2007 at 12:26:12PM +0100, Philipp Reisner (philipp.reisner@linbit.com) wrote: > Hi Evgeniy, Hi Philipp. > When one stresses the connector code, with sending many messages > from userspace to kernel, one could get in the "unlikely()" > part in cn_call_callback(). > > There a new __cbq gets allocated, and a NULL pointer got assigned > to the callback by dereferencing __cbq. This is the bug. The right > thing is the dereference the original __cbq. Therefore the bugfix > is to use a new variable for the newly allocated __cbq. > > This is tested, and it fixes the issue. Yes, your patch is correct. > Signed-off-by: Philipp Reisner > Signed-off-by: Lars Ellenberg I will push it, thanks a lot. -- Evgeniy Polyakov