From patchwork Wed Apr 7 09:29:47 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Yingliang X-Patchwork-Id: 12187533 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 5A959C43460 for ; Wed, 7 Apr 2021 09:26:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 016A2613A7 for ; Wed, 7 Apr 2021 09:26:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234834AbhDGJ0W (ORCPT ); Wed, 7 Apr 2021 05:26:22 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:15941 "EHLO szxga05-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231287AbhDGJ0V (ORCPT ); Wed, 7 Apr 2021 05:26:21 -0400 Received: from DGGEMS406-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4FFf8w31tyzyNbZ; Wed, 7 Apr 2021 17:24:00 +0800 (CST) Received: from huawei.com (10.175.103.91) by DGGEMS406-HUB.china.huawei.com (10.3.19.206) with Microsoft SMTP Server id 14.3.498.0; Wed, 7 Apr 2021 17:26:08 +0800 From: Yang Yingliang To: , , CC: , Subject: [PATCH -next] usb: gadget: tegra-xudc: Fix possible use-after-free in tegra_xudc_remove() Date: Wed, 7 Apr 2021 17:29:47 +0800 Message-ID: <20210407092947.3271507-1-yangyingliang@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Originating-IP: [10.175.103.91] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org This driver's remove path calls cancel_delayed_work(). However, that function does not wait until the work function finishes. This means that the callback function may still be running after the driver's remove function has finished, which would result in a use-after-free. Fix by calling cancel_delayed_work_sync(), which ensures that the work is properly cancelled, no longer running, and unable to re-schedule itself. Reported-by: Hulk Robot Signed-off-by: Yang Yingliang --- drivers/usb/gadget/udc/tegra-xudc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/gadget/udc/tegra-xudc.c b/drivers/usb/gadget/udc/tegra-xudc.c index 580bef8eb4cb..2319c9737c2b 100644 --- a/drivers/usb/gadget/udc/tegra-xudc.c +++ b/drivers/usb/gadget/udc/tegra-xudc.c @@ -3883,7 +3883,7 @@ static int tegra_xudc_remove(struct platform_device *pdev) pm_runtime_get_sync(xudc->dev); - cancel_delayed_work(&xudc->plc_reset_work); + cancel_delayed_work_sync(&xudc->plc_reset_work); cancel_work_sync(&xudc->usb_role_sw_work); usb_del_gadget_udc(&xudc->gadget);