From patchwork Tue Oct 3 07:41:10 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Takashi Iwai X-Patchwork-Id: 9981895 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 583556038E for ; Tue, 3 Oct 2017 07:41:18 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 49E8A27480 for ; Tue, 3 Oct 2017 07:41:18 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3ECC12874C; Tue, 3 Oct 2017 07:41:18 +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=unavailable 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 83129285C3 for ; Tue, 3 Oct 2017 07:41:17 +0000 (UTC) Received: from alsa0.perex.cz (localhost [127.0.0.1]) by alsa0.perex.cz (Postfix) with ESMTP id E65BD2672B3; Tue, 3 Oct 2017 09:41:15 +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 BBE7D2672B4; Tue, 3 Oct 2017 09:41:14 +0200 (CEST) Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by alsa0.perex.cz (Postfix) with ESMTP id 8C2042672AC for ; Tue, 3 Oct 2017 09:41:12 +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 mx1.suse.de (Postfix) with ESMTP id C6C82AAAD; Tue, 3 Oct 2017 07:41:11 +0000 (UTC) Date: Tue, 03 Oct 2017 09:41:10 +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 , =?UTF-8?B?IkhhbnMgUC4gTcO2bGxlciBF?= =?UTF-8?B?Ym5lciI=?= , 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, 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 -- 8< -- From: Takashi Iwai Subject: [PATCH] ALSA: line6: Fix missing initialization before error path The error path in podhd_init() tries to clear the pending timer, while the timer object is initialized at the end of init sequence, thus it may hit the uninitialized object, as spotted by syzkaller: 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 .... For addressing it, assure the initializations of timer and work by moving them to the beginning of podhd_init(). Fixes: 790869dacc3d ("ALSA: line6: Add support for POD X3") Reported-by: Andrey Konovalov Cc: Signed-off-by: Takashi Iwai --- sound/usb/line6/podhd.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/sound/usb/line6/podhd.c b/sound/usb/line6/podhd.c index 956f847a96e4..14ab82ea7e82 100644 --- a/sound/usb/line6/podhd.c +++ b/sound/usb/line6/podhd.c @@ -317,6 +317,9 @@ static int podhd_init(struct usb_line6 *line6, line6->disconnect = podhd_disconnect; + init_timer(&pod->startup_timer); + INIT_WORK(&pod->startup_work, podhd_startup_workqueue); + if (pod->line6.properties->capabilities & LINE6_CAP_CONTROL) { /* claim the data interface */ intf = usb_ifnum_to_if(line6->usbdev, @@ -358,8 +361,6 @@ static int podhd_init(struct usb_line6 *line6, } /* init device and delay registering */ - init_timer(&pod->startup_timer); - INIT_WORK(&pod->startup_work, podhd_startup_workqueue); podhd_startup(pod); return 0; }