From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932134AbVKTXyE (ORCPT ); Sun, 20 Nov 2005 18:54:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932132AbVKTXyE (ORCPT ); Sun, 20 Nov 2005 18:54:04 -0500 Received: from emailhub.stusta.mhn.de ([141.84.69.5]:7953 "HELO mailout.stusta.mhn.de") by vger.kernel.org with SMTP id S932134AbVKTXyD (ORCPT ); Sun, 20 Nov 2005 18:54:03 -0500 Date: Mon, 21 Nov 2005 00:54:02 +0100 From: Adrian Bunk To: Jesper Juhl Cc: bcollins@debian.org, dan@dennedy.org, linux1394-devel@lists.sourceforge.net, scjody@steamballoon.com, linux-kernel@vger.kernel.org, stable@kernel.org Subject: Re: [2.6 patch] drivers/ieee1394/raw1394.c: fix a NULL pointer dereference Message-ID: <20051120235402.GS16060@stusta.de> References: <20051120232009.GH16060@stusta.de> <9a8748490511201545n70e0e6fftd0f1aaf748abe05@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9a8748490511201545n70e0e6fftd0f1aaf748abe05@mail.gmail.com> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 21, 2005 at 12:45:14AM +0100, Jesper Juhl wrote: > On 11/21/05, Adrian Bunk wrote: > > The coverity checker spotted that this was a NULL pointer dereference in > > the "if (copy_from_user(...))" case. > > > > > > Signed-off-by: Adrian Bunk > > > > --- linux-2.6.15-rc1-mm2-full/drivers/ieee1394/raw1394.c.old 2005-11-20 22:08:57.000000000 +0100 > > +++ linux-2.6.15-rc1-mm2-full/drivers/ieee1394/raw1394.c 2005-11-20 22:09:34.000000000 +0100 > > @@ -2166,7 +2166,8 @@ > > } > > } > > } > > - kfree(cache->filled_head); > > + if(cache->filled_head) > > + kfree(cache->filled_head); > > kfree(cache); > > > Hmmm, kfree() deals with NULL pointers just fine, so there's no > problem if cache->filled_head is NULL. There is, however, a NULL > pointer deref problem if `cache' is NULL, but that's not what your > patch checks for. >... OK, I was blind... I've just sent a better patch. cu Adrian -- "Is there not promise of rain?" Ling Tan asked suddenly out of the darkness. There had been need of rain for many days. "Only a promise," Lao Er said. Pearl S. Buck - Dragon Seed