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 6C622C61DA4 for ; Thu, 9 Mar 2023 19:33:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230426AbjCITdB (ORCPT ); Thu, 9 Mar 2023 14:33:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55900 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230130AbjCITcT (ORCPT ); Thu, 9 Mar 2023 14:32:19 -0500 Received: from m12.mail.163.com (m12.mail.163.com [220.181.12.214]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 29464F738E; Thu, 9 Mar 2023 11:31:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id:MIME-Version; bh=OLj0E EDcClubzWEsb6yI7uXbUc6GnDp13HNII7GwMQE=; b=jBcveBzCfUz30qCgMUmJr VASNr0p2y6zNlGygFHgrRwBsPbKHGEubdlA8PmiTkF+K3gw6utYPZDbZDFFph9Lk QgrlHfR0BsPM0dny8UQHBGEGdnMWugVKXcMhuGR6IpdTyOngM65oTNjiaNYNiGbw vfCtbBIa1DFtxqMjjR9wQ0= Received: from leanderwang-LC2.localdomain (unknown [111.206.145.21]) by zwqz-smtp-mta-g0-1 (Coremail) with SMTP id _____wAHKnjOMwpkcqj6Cg--.38073S2; Fri, 10 Mar 2023 03:30:22 +0800 (CST) From: Zheng Wang To: gregkh@linuxfoundation.org Cc: p.zabel@pengutronix.de, biju.das.jz@bp.renesas.com, phil.edworthy@renesas.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, hackerzheng666@gmail.com, 1395428693sheep@gmail.com, alex000young@gmail.com, Zheng Wang Subject: [PATCH] usb: gadget: udc: renesas_usb3: Fix use after free bug in renesas_usb3_remove due to race condition Date: Fri, 10 Mar 2023 03:30:20 +0800 Message-Id: <20230309193020.374950-1-zyytlz.wz@163.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID: _____wAHKnjOMwpkcqj6Cg--.38073S2 X-Coremail-Antispam: 1Uf129KBjvJXoW7tF1DGryfJr47CF4fCF15Arb_yoW8GF4DpF n8GrWrGr48GFy0qwsrGFyDZFyrCFyDKry3ZFWxKa1kuF1rG3y8Xr9Fqa1jkr17JFZ2yr4S q3WUu348tFW7u37anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0zi-eOJUUUUU= X-Originating-IP: [111.206.145.21] X-CM-SenderInfo: h2113zf2oz6qqrwthudrp/1tbiQhAtU1aEEmvBkgAAsU Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In renesas_usb3_probe, &usb3->role_work is bound with renesas_usb3_role_work. renesas_usb3_start will be called to start the work. If we remove the module which will call renesas_usb3_remove to make cleanup, there may be a unfinished work. The possible sequence is as follows: Fix it by canceling the work before cleanup in the renesas_usb3_remove CPU0 CPUc1 |renesas_usb3_role_work renesas_usb3_remove | usb_role_switch_unregister | device_unregister | kfree(sw); | free usb3->role_sw | | usb_role_switch_set_role | //use usb3->role_sw Fixes: 39facfa01c9f ("usb: gadget: udc: renesas_usb3: Add register of usb role switch") Signed-off-by: Zheng Wang --- drivers/usb/gadget/udc/renesas_usb3.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/usb/gadget/udc/renesas_usb3.c b/drivers/usb/gadget/udc/renesas_usb3.c index bee6bceafc4f..23b5f1706d25 100644 --- a/drivers/usb/gadget/udc/renesas_usb3.c +++ b/drivers/usb/gadget/udc/renesas_usb3.c @@ -2658,6 +2658,8 @@ static int renesas_usb3_remove(struct platform_device *pdev) { struct renesas_usb3 *usb3 = platform_get_drvdata(pdev); + cancel_work_sync(&usb3->extcon_work); + cancel_work_sync(&usb3->role_work); debugfs_remove_recursive(usb3->dentry); device_remove_file(&pdev->dev, &dev_attr_role); -- 2.25.1