From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF98AC43441 for ; Tue, 13 Nov 2018 20:38:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 94DD1223C8 for ; Tue, 13 Nov 2018 20:38:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 94DD1223C8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=rowland.harvard.edu Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726955AbeKNGhu (ORCPT ); Wed, 14 Nov 2018 01:37:50 -0500 Received: from iolanthe.rowland.org ([192.131.102.54]:55246 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1726291AbeKNGht (ORCPT ); Wed, 14 Nov 2018 01:37:49 -0500 Received: (qmail 25148 invoked by uid 2102); 13 Nov 2018 15:37:59 -0500 Received: from localhost (sendmail-bs@127.0.0.1) by localhost with SMTP; 13 Nov 2018 15:37:59 -0500 Date: Tue, 13 Nov 2018 15:37:59 -0500 (EST) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: syzbot cc: Thinh.Nguyen@synopsys.com, , , , , , Subject: Re: WARNING in usb_submit_urb (4) In-Reply-To: <000000000000214dc1057a74d206@google.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 12 Nov 2018, syzbot wrote: > syzbot has found a reproducer for the following crash on: > > HEAD commit: e12e00e388de Merge tag 'kbuild-fixes-v4.20' of git://git.k.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=100e4ef5400000 > kernel config: https://syzkaller.appspot.com/x/.config?x=8f215f21f041a0d7 > dashboard link: https://syzkaller.appspot.com/bug?extid=7634edaea4d0b341c625 > compiler: gcc (GCC) 8.0.1 20180413 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11ce6fbd400000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+7634edaea4d0b341c625@syzkaller.appspotmail.com I tried reproducing this bug on my own system, following the instructions at https://github.com/google/syzkaller/blob/master/docs/executing_syzkaller_programs.md The reproducer failed to run properly. It produced the following output: $ ./syz-execprog -cover=0 -threaded=1 -repeat=1 -procs=4 /tmp/repro.syz 2018/11/13 15:29:32 parsed 1 programs 2018/11/13 15:29:32 executed programs: 0 2018/11/13 15:29:32 result: failed=false hanged=false err=executor 3: failed: tun: ioctl(TUNSETIFF) failed (errno 1) loop failed (errno 0) tun: ioctl(TUNSETIFF) failed (errno 1) loop failed (errno 0) The system is Fedora 28 running the 4.18.16-200.fc28.x86_64 kernel. What should I do to investigate further? Alan Stern