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=-19.1 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=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 2D083C433B4 for ; Thu, 20 May 2021 11:20:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 11954613AC for ; Thu, 20 May 2021 11:20:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240930AbhETLVi (ORCPT ); Thu, 20 May 2021 07:21:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:56958 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239098AbhETLBj (ORCPT ); Thu, 20 May 2021 07:01:39 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 69B9E61423; Thu, 20 May 2021 10:03:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621505022; bh=T3kO8RrvNCX8As7P6Z7PFwvA19Yoow54UYuEWBXkQOg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kBzteK5eBY/1Znu3hDRCuWDRppBbb/U0mhteF9ijHxJp8h7WcQSg4DkpVQFFoi+ay 1e6WB1swGPQhIyFiBn/TDDoFkLKtu1c6VIv3u8Jp/G2A3YoxTwwASJn/TAoQvt3nes dMiRa3hzq3hmVUjaB6hNpO2FhlYFvI3K1/7IFJ/I= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Miklos Szeredi , Sasha Levin Subject: [PATCH 4.9 180/240] cuse: prevent clone Date: Thu, 20 May 2021 11:22:52 +0200 Message-Id: <20210520092114.703207137@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210520092108.587553970@linuxfoundation.org> References: <20210520092108.587553970@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Miklos Szeredi [ Upstream commit 8217673d07256b22881127bf50dce874d0e51653 ] For cloned connections cuse_channel_release() will be called more than once, resulting in use after free. Prevent device cloning for CUSE, which does not make sense at this point, and highly unlikely to be used in real life. Signed-off-by: Miklos Szeredi Signed-off-by: Sasha Levin --- fs/fuse/cuse.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c index d9aba9700726..b83367300f48 100644 --- a/fs/fuse/cuse.c +++ b/fs/fuse/cuse.c @@ -616,6 +616,8 @@ static int __init cuse_init(void) cuse_channel_fops.owner = THIS_MODULE; cuse_channel_fops.open = cuse_channel_open; cuse_channel_fops.release = cuse_channel_release; + /* CUSE is not prepared for FUSE_DEV_IOC_CLONE */ + cuse_channel_fops.unlocked_ioctl = NULL; cuse_class = class_create(THIS_MODULE, "cuse"); if (IS_ERR(cuse_class)) -- 2.30.2