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=-5.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 8897FC4CECD for ; Mon, 16 Sep 2019 19:53:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6A8FC206C2 for ; Mon, 16 Sep 2019 19:53:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391049AbfIPTxG (ORCPT ); Mon, 16 Sep 2019 15:53:06 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:51950 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S2391019AbfIPTxG (ORCPT ); Mon, 16 Sep 2019 15:53:06 -0400 Received: (qmail 7108 invoked by uid 2102); 16 Sep 2019 15:53:05 -0400 Received: from localhost (sendmail-bs@127.0.0.1) by localhost with SMTP; 16 Sep 2019 15:53:05 -0400 Date: Mon, 16 Sep 2019 15:53:05 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: syzbot cc: andreyknvl@google.com, , , , , , Subject: Re: INFO: rcu detected stall in dummy_timer In-Reply-To: <0000000000004fb020059274a5ff@google.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Archived-At: List-Archive: List-Post: On Fri, 13 Sep 2019, syzbot wrote: > syzbot has found a reproducer for the following crash on: > > HEAD commit: f0df5c1b usb-fuzzer: main usb gadget fuzzer driver > git tree: https://github.com/google/kasan.git usb-fuzzer > console output: https://syzkaller.appspot.com/x/log.txt?x=1146550d600000 > kernel config: https://syzkaller.appspot.com/x/.config?x=5c6633fa4ed00be5 > dashboard link: https://syzkaller.appspot.com/bug?extid=b24d736f18a1541ad550 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11203fa5600000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=162cd335600000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+b24d736f18a1541ad550@syzkaller.appspotmail.com > > yurex 3-1:0.101: yurex_interrupt - unknown status received: -71 > yurex 5-1:0.101: yurex_interrupt - unknown status received: -71 > yurex 6-1:0.101: yurex_interrupt - unknown status received: -71 Let's see if preventing blind resubmissions fixes the problem. Alan Stern #syz test: https://github.com/google/kasan.git f0df5c1b drivers/usb/misc/yurex.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) Index: usb-devel/drivers/usb/misc/yurex.c =================================================================== --- usb-devel.orig/drivers/usb/misc/yurex.c +++ usb-devel/drivers/usb/misc/yurex.c @@ -132,6 +132,7 @@ static void yurex_interrupt(struct urb * switch (status) { case 0: /*success*/ break; + /* The device is terminated or messed up, give up */ case -EOVERFLOW: dev_err(&dev->interface->dev, "%s - overflow with length %d, actual length is %d\n", @@ -140,12 +141,12 @@ static void yurex_interrupt(struct urb * case -ENOENT: case -ESHUTDOWN: case -EILSEQ: - /* The device is terminated, clean up */ + case -EPROTO: return; default: dev_err(&dev->interface->dev, "%s - unknown status received: %d\n", __func__, status); - goto exit; + return; } /* handle received message */ @@ -177,7 +178,6 @@ static void yurex_interrupt(struct urb * break; } -exit: retval = usb_submit_urb(dev->urb, GFP_ATOMIC); if (retval) { dev_err(&dev->interface->dev, "%s - usb_submit_urb failed: %d\n",