From mboxrd@z Thu Jan 1 00:00:00 1970 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 2EA79FA3728 for ; Wed, 16 Oct 2019 22:21:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 06BF3207FF for ; Wed, 16 Oct 2019 22:21:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571264461; bh=heFOay0TYzWjNvKYNEz8ViFfCH3YlYJUtQpL2khwNhU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=CEaGQ7N8oEUgKXiO9FSbRlCZuorHf60LitJNFjjtfv+Rn8XL7Vwl3rBVpghewLUou ygQnjs+cJ6bIKxE1ud2MPDBYq7D4yqDjmLRWt6Vl2FYD97xwbZyuuq4RP8VJr5PDsQ aMIwju9fgjo0hkaN9eRXlRaTNZ2bsxY/TNxsksJI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2407532AbfJPWUz (ORCPT ); Wed, 16 Oct 2019 18:20:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:42784 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2437568AbfJPVxl (ORCPT ); Wed, 16 Oct 2019 17:53:41 -0400 Received: from localhost (unknown [192.55.54.58]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7D2E721D7C; Wed, 16 Oct 2019 21:53:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571262820; bh=heFOay0TYzWjNvKYNEz8ViFfCH3YlYJUtQpL2khwNhU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VXynawIR6D/yYgF8iKRO6lECNPExK9Mj66E38pVcUVCweVTvEcr3IdJRSTnpgeA6b DXePGmo98OsSQQGS9RuglkzX/8xPcbGZU1KfJcHEjB/0veETIZRfRKn/Ipk7tCnD4y 45Y+KOrkmX7B6w/ADCiHL5qICbkoutVKSBmCrjSU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johan Hovold Subject: [PATCH 4.4 63/79] USB: legousbtower: fix use-after-free on release Date: Wed, 16 Oct 2019 14:50:38 -0700 Message-Id: <20191016214825.045855955@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191016214729.758892904@linuxfoundation.org> References: <20191016214729.758892904@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Johan Hovold commit 726b55d0e22ca72c69c947af87785c830289ddbc upstream. The driver was accessing its struct usb_device in its release() callback without holding a reference. This would lead to a use-after-free whenever the device was disconnected while the character device was still open. Fixes: fef526cae700 ("USB: legousbtower: remove custom debug macro") Cc: stable # 3.12 Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20191009153848.8664-5-johan@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/usb/misc/legousbtower.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/usb/misc/legousbtower.c +++ b/drivers/usb/misc/legousbtower.c @@ -302,6 +302,7 @@ static inline void tower_delete (struct kfree (dev->read_buffer); kfree (dev->interrupt_in_buffer); kfree (dev->interrupt_out_buffer); + usb_put_dev(dev->udev); kfree (dev); } @@ -820,7 +821,7 @@ static int tower_probe (struct usb_inter mutex_init(&dev->lock); - dev->udev = udev; + dev->udev = usb_get_dev(udev); dev->open_count = 0; dev->disconnected = 0;