From patchwork Mon Apr 26 07:29:27 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 427905 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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 F34C8C43460 for ; Mon, 26 Apr 2021 07:33:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C952E61004 for ; Mon, 26 Apr 2021 07:33:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232638AbhDZHdo (ORCPT ); Mon, 26 Apr 2021 03:33:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:45964 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232257AbhDZHdl (ORCPT ); Mon, 26 Apr 2021 03:33:41 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D0384611BF; Mon, 26 Apr 2021 07:32:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1619422379; bh=FOVNsP37ujZU56ZO0D/Mg7ahp3v4DxwECQ6+MyBv7tE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Lur5EpmLNh1/LlGkQqlEcI9SIjXnioAcCfCBePQfZ6AH/gjRkcbUWAcWrMDnMVnas qIdDTHjnblQr5k6eCs01xWv+y6761v4ncLI2sG9TWmSnJoRtCKgx4MzC0iLrT3Xugb 4pY+4reR13s2S1yFx4CKh4jeT1Dsa3xS7VDOox7s= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , Shuah Khan , Tom Seewald , syzbot+a93fba6d384346a761e3@syzkaller.appspotmail.com Subject: [PATCH 4.9 26/37] usbip: vudc synchronize sysfs code paths Date: Mon, 26 Apr 2021 09:29:27 +0200 Message-Id: <20210426072818.135957668@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210426072817.245304364@linuxfoundation.org> References: <20210426072817.245304364@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Shuah Khan commit bd8b82042269a95db48074b8bb400678dbac1815 upstream. Fuzzing uncovered race condition between sysfs code paths in usbip drivers. Device connect/disconnect code paths initiated through sysfs interface are prone to races if disconnect happens during connect and vice versa. Use sysfs_lock to protect sysfs paths in vudc. Cc: stable@vger.kernel.org # 4.9.x # 4.14.x Reported-and-tested-by: syzbot+a93fba6d384346a761e3@syzkaller.appspotmail.com Signed-off-by: Shuah Khan Link: https://lore.kernel.org/r/caabcf3fc87bdae970509b5ff32d05bb7ce2fb15.1616807117.git.skhan@linuxfoundation.org Signed-off-by: Tom Seewald Signed-off-by: Greg Kroah-Hartman --- drivers/usb/usbip/vudc_dev.c | 1 + drivers/usb/usbip/vudc_sysfs.c | 5 +++++ 2 files changed, 6 insertions(+) --- a/drivers/usb/usbip/vudc_dev.c +++ b/drivers/usb/usbip/vudc_dev.c @@ -582,6 +582,7 @@ static int init_vudc_hw(struct vudc *udc init_waitqueue_head(&udc->tx_waitq); spin_lock_init(&ud->lock); + mutex_init(&ud->sysfs_lock); ud->status = SDEV_ST_AVAILABLE; ud->side = USBIP_VUDC; --- a/drivers/usb/usbip/vudc_sysfs.c +++ b/drivers/usb/usbip/vudc_sysfs.c @@ -125,6 +125,7 @@ static ssize_t store_sockfd(struct devic dev_err(dev, "no device"); return -ENODEV; } + mutex_lock(&udc->ud.sysfs_lock); spin_lock_irqsave(&udc->lock, flags); /* Don't export what we don't have */ if (!udc->driver || !udc->pullup) { @@ -200,6 +201,8 @@ static ssize_t store_sockfd(struct devic wake_up_process(udc->ud.tcp_rx); wake_up_process(udc->ud.tcp_tx); + + mutex_unlock(&udc->ud.sysfs_lock); return count; } else { @@ -220,6 +223,7 @@ static ssize_t store_sockfd(struct devic } spin_unlock_irqrestore(&udc->lock, flags); + mutex_unlock(&udc->ud.sysfs_lock); return count; @@ -229,6 +233,7 @@ unlock_ud: spin_unlock_irq(&udc->ud.lock); unlock: spin_unlock_irqrestore(&udc->lock, flags); + mutex_unlock(&udc->ud.sysfs_lock); return ret; }