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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 C81DEC2D0C6 for ; Wed, 11 Dec 2019 15:47:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 96C492073B for ; Wed, 11 Dec 2019 15:47:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576079269; bh=GQf7xfv2YSUiwk6NBiWJ5TOV2wjL24/2H9jtq5OK+xA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=z6JT46nj//XHXOFQUMVt7u5QrOYbtQYr7o5MQQA3F5TEfUVdgA0ZFQuSMfSNdgv4u QU9q02xxgE90/dtVRVC633sd5f+NENBIuLLzsGajgMYVVi4vNPhlRyY+3c0hUlYr3Z LpITHPnglL1Sx9s5DGcvpB4NNmAFS4A6XeLdi0GQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387869AbfLKPrs (ORCPT ); Wed, 11 Dec 2019 10:47:48 -0500 Received: from mail.kernel.org ([198.145.29.99]:59054 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733070AbfLKP0I (ORCPT ); Wed, 11 Dec 2019 10:26:08 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4A74F22527; Wed, 11 Dec 2019 15:26:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576077967; bh=GQf7xfv2YSUiwk6NBiWJ5TOV2wjL24/2H9jtq5OK+xA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tyG+QzvoBf0hkCWTLincoAHonMFmv0yrS7QxyzS5jUo4i4CcNz1yIDVCBPADSdrma 8ytRQIlhyLHDcUy1N2P6lB/uIkKv5NNSmblW71plpJHthgJwj+h0Oc+DUEPdD0EwMA 1nsEuomaEJOuMN9VY7wm87PqY+AaEJHE7qgPIHhw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Wei Wang , Zhang Rui Subject: [PATCH 4.19 240/243] thermal: Fix deadlock in thermal thermal_zone_device_check Date: Wed, 11 Dec 2019 16:06:42 +0100 Message-Id: <20191211150355.539425324@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191211150339.185439726@linuxfoundation.org> References: <20191211150339.185439726@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wei Wang commit 163b00cde7cf2206e248789d2780121ad5e6a70b upstream. 1851799e1d29 ("thermal: Fix use-after-free when unregistering thermal zone device") changed cancel_delayed_work to cancel_delayed_work_sync to avoid a use-after-free issue. However, cancel_delayed_work_sync could be called insides the WQ causing deadlock. [54109.642398] c0 1162 kworker/u17:1 D 0 11030 2 0x00000000 [54109.642437] c0 1162 Workqueue: thermal_passive_wq thermal_zone_device_check [54109.642447] c0 1162 Call trace: [54109.642456] c0 1162 __switch_to+0x138/0x158 [54109.642467] c0 1162 __schedule+0xba4/0x1434 [54109.642480] c0 1162 schedule_timeout+0xa0/0xb28 [54109.642492] c0 1162 wait_for_common+0x138/0x2e8 [54109.642511] c0 1162 flush_work+0x348/0x40c [54109.642522] c0 1162 __cancel_work_timer+0x180/0x218 [54109.642544] c0 1162 handle_thermal_trip+0x2c4/0x5a4 [54109.642553] c0 1162 thermal_zone_device_update+0x1b4/0x25c [54109.642563] c0 1162 thermal_zone_device_check+0x18/0x24 [54109.642574] c0 1162 process_one_work+0x3cc/0x69c [54109.642583] c0 1162 worker_thread+0x49c/0x7c0 [54109.642593] c0 1162 kthread+0x17c/0x1b0 [54109.642602] c0 1162 ret_from_fork+0x10/0x18 [54109.643051] c0 1162 kworker/u17:2 D 0 16245 2 0x00000000 [54109.643067] c0 1162 Workqueue: thermal_passive_wq thermal_zone_device_check [54109.643077] c0 1162 Call trace: [54109.643085] c0 1162 __switch_to+0x138/0x158 [54109.643095] c0 1162 __schedule+0xba4/0x1434 [54109.643104] c0 1162 schedule_timeout+0xa0/0xb28 [54109.643114] c0 1162 wait_for_common+0x138/0x2e8 [54109.643122] c0 1162 flush_work+0x348/0x40c [54109.643131] c0 1162 __cancel_work_timer+0x180/0x218 [54109.643141] c0 1162 handle_thermal_trip+0x2c4/0x5a4 [54109.643150] c0 1162 thermal_zone_device_update+0x1b4/0x25c [54109.643159] c0 1162 thermal_zone_device_check+0x18/0x24 [54109.643167] c0 1162 process_one_work+0x3cc/0x69c [54109.643177] c0 1162 worker_thread+0x49c/0x7c0 [54109.643186] c0 1162 kthread+0x17c/0x1b0 [54109.643195] c0 1162 ret_from_fork+0x10/0x18 [54109.644500] c0 1162 cat D 0 7766 1 0x00000001 [54109.644515] c0 1162 Call trace: [54109.644524] c0 1162 __switch_to+0x138/0x158 [54109.644536] c0 1162 __schedule+0xba4/0x1434 [54109.644546] c0 1162 schedule_preempt_disabled+0x80/0xb0 [54109.644555] c0 1162 __mutex_lock+0x3a8/0x7f0 [54109.644563] c0 1162 __mutex_lock_slowpath+0x14/0x20 [54109.644575] c0 1162 thermal_zone_get_temp+0x84/0x360 [54109.644586] c0 1162 temp_show+0x30/0x78 [54109.644609] c0 1162 dev_attr_show+0x5c/0xf0 [54109.644628] c0 1162 sysfs_kf_seq_show+0xcc/0x1a4 [54109.644636] c0 1162 kernfs_seq_show+0x48/0x88 [54109.644656] c0 1162 seq_read+0x1f4/0x73c [54109.644664] c0 1162 kernfs_fop_read+0x84/0x318 [54109.644683] c0 1162 __vfs_read+0x50/0x1bc [54109.644692] c0 1162 vfs_read+0xa4/0x140 [54109.644701] c0 1162 SyS_read+0xbc/0x144 [54109.644708] c0 1162 el0_svc_naked+0x34/0x38 [54109.845800] c0 1162 D 720.000s 1->7766->7766 cat [panic] Fixes: 1851799e1d29 ("thermal: Fix use-after-free when unregistering thermal zone device") Cc: stable@vger.kernel.org Signed-off-by: Wei Wang Signed-off-by: Zhang Rui Signed-off-by: Greg Kroah-Hartman --- drivers/thermal/thermal_core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -296,7 +296,7 @@ static void thermal_zone_device_set_poll mod_delayed_work(system_freezable_wq, &tz->poll_queue, msecs_to_jiffies(delay)); else - cancel_delayed_work_sync(&tz->poll_queue); + cancel_delayed_work(&tz->poll_queue); } static void monitor_thermal_zone(struct thermal_zone_device *tz) @@ -1349,7 +1349,7 @@ void thermal_zone_device_unregister(stru mutex_unlock(&thermal_list_lock); - thermal_zone_device_set_polling(tz, 0); + cancel_delayed_work_sync(&tz->poll_queue); thermal_set_governor(tz, NULL);