From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753446Ab2JONQn (ORCPT ); Mon, 15 Oct 2012 09:16:43 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35594 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753325Ab2JONQm (ORCPT ); Mon, 15 Oct 2012 09:16:42 -0400 Date: Mon, 15 Oct 2012 09:16:36 -0400 From: Aristeu Rozanski To: Sasha Levin Cc: Tejun Heo , dan.carpenter@oracle.com, fengguang.wu@intel.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] xattr: prevent NULL ptr deref warnings in __simple_xattr_set Message-ID: <20121015131636.GD29956@redhat.com> References: <1347651354-16289-1-git-send-email-levinsasha928@gmail.com> <1347651354-16289-2-git-send-email-levinsasha928@gmail.com> <20120914205434.GS17747@google.com> <20120914205555.GT17747@google.com> <20120914205849.GS19694@redhat.com> <5074725F.6090804@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5074725F.6090804@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sasha, On Tue, Oct 09, 2012 at 02:52:15PM -0400, Sasha Levin wrote: > On 09/14/2012 04:58 PM, Aristeu Rozanski wrote: > > On Fri, Sep 14, 2012 at 01:55:55PM -0700, Tejun Heo wrote: > >> On Fri, Sep 14, 2012 at 01:54:34PM -0700, Tejun Heo wrote: > >>> On Fri, Sep 14, 2012 at 09:35:54PM +0200, Sasha Levin wrote: > >>>> Prevent warnings generated by smatch due to unchecked dereference of > >>>> 'new_xattr' in __simple_xattr_set(). > >>> > >>> Isn't this an actual bug w/ or w/o smatch? Remove request (NULL > >>> @value) w/o XATTR_REPLACE for an non-existent node would end up > >>> calling list_add() on NULL, right? If so, please collapse these two > >>> patches and mention the actual bug instead of smatch warning. > >> > >> And can somebody please make that function less confusing? - > >> restructuring / commenting whatever. It's doing something simple. > >> It's not supposed to be this confusing. > > > > I'll work on that. > > > > As it's still happening in linux-next, should I send a simple patch to fix it along > with Tejun's comments? Or is the rewrite of __simple_xattr_set() behind the corner? the problem isn't because of the way __simple_xattr_set(), but because the fix took another route and wasn't present when you hit it last. -- Aristeu