From patchwork Thu Mar 16 17:44:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zheng Wang X-Patchwork-Id: 664981 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 491D3C7618E for ; Thu, 16 Mar 2023 17:45:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230133AbjCPRpI (ORCPT ); Thu, 16 Mar 2023 13:45:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43948 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229895AbjCPRot (ORCPT ); Thu, 16 Mar 2023 13:44:49 -0400 Received: from m12.mail.163.com (m12.mail.163.com [220.181.12.216]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 5AA3749F3; Thu, 16 Mar 2023 10:44:46 -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=nEAMn AlTlhmBc3GQSHDUq/SQ1R/Wav9t7BfHo/zL+ZI=; b=eFIIFAUwP5fDPLIp7KfFk 55oJJ5VNga9gWULLyFnBxMJEwVyYIPd0/yM18xNy31DuP0Fmx1oUfVw91R8YHcUQ RFbXqF1bzzDhS3t4jiqB1GQrRgxgmVzToi2m0Vrsc3EFd+B0hcJlbXCOxQ0kYPdW 12oS+GZipHGfykDngcnBCA= Received: from leanderwang-LC2.localdomain (unknown [111.206.145.21]) by zwqz-smtp-mta-g4-0 (Coremail) with SMTP id _____wD3_8eBVRNkg0sdAQ--.31373S2; Fri, 17 Mar 2023 01:44:33 +0800 (CST) From: Zheng Wang To: valentina.manea.m@gmail.com Cc: shuah@kernel.org, gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, hackerzheng666@gmail.com, 1395428693sheep@gmail.com, alex000young@gmail.com, Zheng Wang Subject: [PATCH v3] usbip: vudc: Fix use after free bug in vudc_remove due to race condition Date: Fri, 17 Mar 2023 01:44:32 +0800 Message-Id: <20230316174432.1592087-1-zyytlz.wz@163.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-CM-TRANSID: _____wD3_8eBVRNkg0sdAQ--.31373S2 X-Coremail-Antispam: 1Uf129KBjvdXoWrtF1UGFy5Jw45ZF18GrWkXrb_yoWkXwc_ua 4ruF4xGF4rCanxKF17XwnxZrWUKFyDXrn3XFs29F4fWa4xGr15Zw17Ars7uF47uF98GFyD Cws8t395Zw47ujkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7xRK9NVJUUUUU== X-Originating-IP: [111.206.145.21] X-CM-SenderInfo: h2113zf2oz6qqrwthudrp/1tbiXQU0U1WBo8O2kQAAss Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org In vudc_probe, it calls init_vudc_hw, which bound &udc->timer with v_timer. When it calls usbip_sockfd_store, it will call v_start_timer to start the timer work. When we call vudc_remove to remove the driver, theremay be a sequence as follows: Fix it by shutdown the timer work before cleanup in vudc_remove. Note that removing a driver is a root-only operation, and should never happen. CPU0 CPU1 |v_timer vudc_remove | kfree(udc); | //free shost | |udc->gadget |//use Fixes: b6a0ca111867 ("usbip: vudc: Add UDC specific ops") Signed-off-by: Zheng Wang --- drivers/usb/usbip/vudc_dev.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/usb/usbip/vudc_dev.c b/drivers/usb/usbip/vudc_dev.c index 2bc428f2e261..33d0991755bb 100644 --- a/drivers/usb/usbip/vudc_dev.c +++ b/drivers/usb/usbip/vudc_dev.c @@ -633,6 +633,7 @@ int vudc_remove(struct platform_device *pdev) { struct vudc *udc = platform_get_drvdata(pdev); + timer_shutdown_sync(&udc->timer); usb_del_gadget_udc(&udc->gadget); cleanup_vudc_hw(udc); kfree(udc);