From patchwork Thu Apr 13 15:43:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zheng Wang X-Patchwork-Id: 13210402 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A2118C77B61 for ; Thu, 13 Apr 2023 15:44:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231519AbjDMPoS (ORCPT ); Thu, 13 Apr 2023 11:44:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33260 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229633AbjDMPoR (ORCPT ); Thu, 13 Apr 2023 11:44:17 -0400 Received: from m12.mail.163.com (m12.mail.163.com [220.181.12.215]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 3913310EF; Thu, 13 Apr 2023 08:44:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id:MIME-Version; bh=sXqNs 6lg+IIJ+O1PdH2eS9ZXTmGxoGzuMU3zSlyWTwU=; b=To8EJTqEiLT2b/MoWMK5Q Rtj93+txGBKWM+MorhT/fsGWGdWpxxYBEdiQNVDRHMM9r7GFEtuzNSsOfXkufbx4 OXQDyiypLYdRuTbV9b4xPzksnRBPm+rE1YeRH1EprvIk2KCRMvfGTX8niJAbc+5W U75tr5rnADbHUZVMyfx5Ig= Received: from leanderwang-LC2.localdomain (unknown [111.206.145.21]) by zwqz-smtp-mta-g4-4 (Coremail) with SMTP id _____wBXhWY5IzhkpE9VBQ--.3426S2; Thu, 13 Apr 2023 23:43:53 +0800 (CST) From: Zheng Wang To: gregkh@linuxfoundation.org Cc: yoshihiro.shimoda.uh@renesas.com, p.zabel@pengutronix.de, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, hackerzheng666@gmail.com, 1395428693sheep@gmail.com, alex000young@gmail.com, Zheng Wang Subject: [PATCH v2] usb: renesas_usbhs: Fix use after free bug in usbhs_remove due to race condition Date: Thu, 13 Apr 2023 23:43:51 +0800 Message-Id: <20230413154351.619730-1-zyytlz.wz@163.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-CM-TRANSID: _____wBXhWY5IzhkpE9VBQ--.3426S2 X-Coremail-Antispam: 1Uf129KBjvJXoW7Ww13Gw1rKw47WF1UurWDCFg_yoW8Gr13pa 15JFyUG3yrGrWjga1vqr4UXryrCayqgry7WrZrWwsxuwnxAa18Za40qF4Uur13Xa93JF4j vw1vyr95ZaykCFDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0z_9N3DUUUUU= X-Originating-IP: [111.206.145.21] X-CM-SenderInfo: h2113zf2oz6qqrwthudrp/1tbiQhpQU1aEE+iaiQAAsh Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org In usbhs_probe, &priv->notify_hotplug_work is bound with usbhsc_notify_hotplug. It will be started then. If we remove the driver which will call usbhs_remove to make cleanup, there may be a unfinished work. The possible sequence is as follows: Fix it by finishing the work before cleanup in the usbhs_remove CPU0 CPU1 | usbhsc_notify_hotplug usbhs_remove | usbhs_mod_remove | usbhs_mod_gadget_remove | kfree(gpriv); | | usbhsc_hotplug | usbhs_mod_call start | usbhsg_start | usbhsg_try_start | //use gpriv Fixes: bc57381e6347 ("usb: renesas_usbhs: use delayed_work instead of work_struct") Signed-off-by: Zheng Wang --- v2: - beautify the format as Yoshihiro Shimoda suggested --- drivers/usb/renesas_usbhs/common.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/usb/renesas_usbhs/common.c b/drivers/usb/renesas_usbhs/common.c index 96f3939a65e2..17a0987ef4f5 100644 --- a/drivers/usb/renesas_usbhs/common.c +++ b/drivers/usb/renesas_usbhs/common.c @@ -768,6 +768,7 @@ static int usbhs_remove(struct platform_device *pdev) dev_dbg(&pdev->dev, "usb remove\n"); + cancel_delayed_work_sync(&priv->notify_hotplug_work); /* power off */ if (!usbhs_get_dparam(priv, runtime_pwctrl)) usbhsc_power_ctrl(priv, 0);