From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755279AbcDGG7m (ORCPT ); Thu, 7 Apr 2016 02:59:42 -0400 Received: from mx2.suse.de ([195.135.220.15]:48907 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754892AbcDGG7l (ORCPT ); Thu, 7 Apr 2016 02:59:41 -0400 Message-ID: <1460012378.17679.1.camel@suse.com> Subject: Re: Oops in 4.6-rc2: NULL pointer dereference in cdc-acm From: Oliver Neukum To: Gabriele Mazzotta Cc: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Date: Thu, 07 Apr 2016 08:59:38 +0200 In-Reply-To: <5705762E.4040206@gmail.com> References: <5705762E.4040206@gmail.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.11 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2016-04-06 at 22:48 +0200, Gabriele Mazzotta wrote: > Hi, > > I'm getting a kernel oops when I plug some smartphone via USB to my > laptop, which is currently running the v4.6-rc2. > > The problem seems to be caused by a81cf9799ad7 ("cdc-acm: implement > put_char() and flush_chars()"). > > A simple NULL pointer check prevents the crash, but since I have no > use of cdc-acm and I didn't read the code, I don't know if some other > changes are required. > > Here below you can find the change I did to prevent the crash and > the dmesg showing the problem. Hi, thank you for reporting this. You are the second one to report it. I send a fix upstream last week. Greg, can we merge this for the next rc? People are hitting this bug. Regards Oliver