Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751484AbdFGPPq (ORCPT ); Wed, 7 Jun 2017 11:15:46 -0400 Received: from mail-yw0-f173.google.com ([209.85.161.173]:34811 "EHLO mail-yw0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751049AbdFGPPo (ORCPT ); Wed, 7 Jun 2017 11:15:44 -0400 MIME-Version: 1.0 In-Reply-To: References: From: Andrey Konovalov Date: Wed, 7 Jun 2017 17:15:42 +0200 Message-ID: Subject: Re: usb/gadget: another GPF in usb_gadget_unregister_driver To: Alan Stern Cc: Felipe Balbi , Greg Kroah-Hartman , Peter Chen , Krzysztof Opasiak , Colin Ian King , =?UTF-8?Q?Felix_H=C3=A4dicke?= , Roger Quadros , USB list , LKML , Dmitry Vyukov , Kostya Serebryany , syzkaller Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1151 Lines: 36 On Wed, Jun 7, 2017 at 4:43 PM, Alan Stern wrote: > On Wed, 7 Jun 2017, Andrey Konovalov wrote: > >> Hi, >> >> I've got the following error report while fuzzing the kernel with syzkaller. >> >> On commit b29794ec95c6856b316c2295904208bf11ffddd9 (4.12-rc4+). >> >> This looks quite similar to >> https://groups.google.com/forum/#!topic/syzkaller/HDawLBeeORI > > It does look very similar, but that problem was supposed to have been > fixed by commit 7b0173811260 ("usb: gadget: udc: core: fix return code > of usb_gadget_probe_driver()"). > >> I'm able to reproduce this, so I can collect some debug traces if needed. > > Can you provide an strace or the equivalent? Here's the syzkaller program (which is actually two programs executed consequently): https://gist.github.com/xairy/fe0a7531e00df5e8bc23e2e56e413510 Here's the strace log: https://gist.github.com/xairy/5fadc3b5d8b2b80c97e566538de08bc4 Unfortunately there's a lot of unrelated garbage, but I can't extract a simple C reproducer. I can also apply patches with debug printk's, run the reproducer and send you the result if that will help. > > Alan Stern >