From patchwork Mon Oct 9 12:31:58 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Takashi Iwai X-Patchwork-Id: 9992847 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4407B602D7 for ; Mon, 9 Oct 2017 12:32:10 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3488C287BF for ; Mon, 9 Oct 2017 12:32:10 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 292C6287C1; Mon, 9 Oct 2017 12:32:10 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 187F7287BF for ; Mon, 9 Oct 2017 12:32:07 +0000 (UTC) Received: from alsa0.perex.cz (localhost [127.0.0.1]) by alsa0.perex.cz (Postfix) with ESMTP id 335FA2670BE; Mon, 9 Oct 2017 14:32:05 +0200 (CEST) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa0.perex.cz (Postfix, from userid 1000) id 9AEF32671FB; Mon, 9 Oct 2017 14:32:04 +0200 (CEST) Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by alsa0.perex.cz (Postfix) with ESMTP id 794512670BC for ; Mon, 9 Oct 2017 14:32:01 +0200 (CEST) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id A0B08ABB8; Mon, 9 Oct 2017 12:32:00 +0000 (UTC) Date: Mon, 09 Oct 2017 14:31:58 +0200 Message-ID: From: Takashi Iwai To: Andrey Konovalov In-Reply-To: References: User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/25.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Cc: alsa-devel@alsa-project.org, Andrej Krutak , LKML , Kostya Serebryany , syzkaller , "Hans P. =?UTF-8?B?TcO2bGxlcg==?= Ebner" , Dmitry Vyukov Subject: Re: [alsa-devel] usb/sound/line6: trying to register non-static key in podhd_disconnect X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org X-Virus-Scanned: ClamAV using ClamSMTP On Mon, 09 Oct 2017 12:58:59 +0200, Andrey Konovalov wrote: > > On Tue, Oct 3, 2017 at 9:41 AM, Takashi Iwai wrote: > > On Mon, 25 Sep 2017 14:40:08 +0200, > > Andrey Konovalov wrote: > >> > >> Hi! > >> > >> I've got the following report while fuzzing the kernel with syzkaller. > >> > >> On commit e19b205be43d11bff638cad4487008c48d21c103 (4.14-rc2). > >> > >> INFO: trying to register non-static key. > >> the code is fine but needs lockdep annotation. > >> turning off the locking correctness validator. > >> CPU: 1 PID: 1845 Comm: kworker/1:2 Not tainted > >> 4.14.0-rc2-42613-g1488251d1a98 #238 > >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 > >> Workqueue: usb_hub_wq hub_event > >> Call Trace: > >> __dump_stack lib/dump_stack.c:16 > >> dump_stack+0x292/0x395 lib/dump_stack.c:52 > >> register_lock_class+0x6c4/0x1a00 kernel/locking/lockdep.c:769 > >> __lock_acquire+0x27e/0x4550 kernel/locking/lockdep.c:3385 > >> lock_acquire+0x259/0x620 kernel/locking/lockdep.c:4002 > >> del_timer_sync+0x12c/0x280 kernel/time/timer.c:1237 > >> podhd_disconnect+0x8c/0x160 sound/usb/line6/podhd.c:299 > >> line6_probe+0x844/0x1310 sound/usb/line6/driver.c:783 > >> podhd_probe+0x64/0x70 sound/usb/line6/podhd.c:474 > >> usb_probe_interface+0x35d/0x8e0 drivers/usb/core/driver.c:361 > >> really_probe drivers/base/dd.c:413 > >> driver_probe_device+0x610/0xa00 drivers/base/dd.c:557 > >> __device_attach_driver+0x230/0x290 drivers/base/dd.c:653 > >> bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463 > >> __device_attach+0x26e/0x3d0 drivers/base/dd.c:710 > >> device_initial_probe+0x1f/0x30 drivers/base/dd.c:757 > >> bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523 > >> device_add+0xd0b/0x1660 drivers/base/core.c:1835 > >> usb_set_configuration+0x104e/0x1870 drivers/usb/core/message.c:1932 > >> generic_probe+0x73/0xe0 drivers/usb/core/generic.c:174 > >> usb_probe_device+0xaf/0xe0 drivers/usb/core/driver.c:266 > >> really_probe drivers/base/dd.c:413 > >> driver_probe_device+0x610/0xa00 drivers/base/dd.c:557 > >> __device_attach_driver+0x230/0x290 drivers/base/dd.c:653 > >> bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463 > >> __device_attach+0x26e/0x3d0 drivers/base/dd.c:710 > >> device_initial_probe+0x1f/0x30 drivers/base/dd.c:757 > >> bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523 > >> device_add+0xd0b/0x1660 drivers/base/core.c:1835 > >> usb_new_device+0x7b8/0x1020 drivers/usb/core/hub.c:2457 > >> hub_port_connect drivers/usb/core/hub.c:4903 > >> hub_port_connect_change drivers/usb/core/hub.c:5009 > >> port_event drivers/usb/core/hub.c:5115 > >> hub_event+0x194d/0x3740 drivers/usb/core/hub.c:5195 > >> process_one_work+0xc7f/0x1db0 kernel/workqueue.c:2119 > >> worker_thread+0x221/0x1850 kernel/workqueue.c:2253 > >> kthread+0x3a1/0x470 kernel/kthread.c:231 > >> ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 > > > > This looks like an access to the uninitialized timer object. > > Could you check the patch below whether it fixes the issue? > > Thanks! > > > > > > Takashi > > Hi Takashi, > > I've applied your patch and now get GPF on > usb_driver_release_interface(&podhd_driver, intf): Another day, another Oops... The patch below should cover it. I'm going to queue both now. thanks, Takashi -- 8< -- From: Takashi Iwai Subject: [PATCH] ALSA: line6: Fix NULL dereference at podhd_disconnect() When podhd_init() failed with the acquiring a ctrl i/f, the line6 helper still calls the disconnect callback that eventually calls again usb_driver_release_interface() with the NULL intf. Put the proper NULL check before calling it for avoiding an Oops. Fixes: fc90172ba283 ("ALSA: line6: Claim pod x3 usb data interface") Reported-by: Andrey Konovalov Cc: Signed-off-by: Takashi Iwai --- sound/usb/line6/podhd.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/sound/usb/line6/podhd.c b/sound/usb/line6/podhd.c index 956f847a96e4..cfcd80092a54 100644 --- a/sound/usb/line6/podhd.c +++ b/sound/usb/line6/podhd.c @@ -301,7 +301,8 @@ static void podhd_disconnect(struct usb_line6 *line6) intf = usb_ifnum_to_if(line6->usbdev, pod->line6.properties->ctrl_if); - usb_driver_release_interface(&podhd_driver, intf); + if (intf) + usb_driver_release_interface(&podhd_driver, intf); } }