From patchwork Sun Oct 21 16:15:03 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 10650945 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id ACC6969B4 for ; Sun, 21 Oct 2018 16:15:19 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9CC15287BE for ; Sun, 21 Oct 2018 16:15:19 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 908E1287C0; Sun, 21 Oct 2018 16:15:19 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 46AE1287C7 for ; Sun, 21 Oct 2018 16:15:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727803AbeJVAaC (ORCPT ); Sun, 21 Oct 2018 20:30:02 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:39268 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727724AbeJVAaC (ORCPT ); Sun, 21 Oct 2018 20:30:02 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w9LGEI3o154168; Sun, 21 Oct 2018 16:15:08 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : from : to : cc : date : message-id : mime-version : content-type : content-transfer-encoding; s=corp-2018-07-02; bh=zQALILQr9U+7OIPR4EjpK3HtCxxS0f5CSoa6TXZMX6o=; b=UIlaj9RmecaEACAKA6O2uap6uo2Z3jO8sksLpNKRiuxLHDZ1Xk5L+gMfDTza5/ra2wSg VJtRXDQ3RhOI2QNHjuy7vIgm6EgYTGGY3RhOzmPwtmN1UxWQjKoQmHgcCOSg5eaPh2aT iDmlTM+2tWZf193L5DtJsf9kz7SILzkb40DCIoeBAqSLA28PtCjmLL3/kq+PJgnmPoDe Ms6m+TG1NDUnDe0JP2OJjbUmyFKO00l+m6Aj7GnW0Ud4A7elXm9WXc7yc8BUXcjzjjcV 2iIbqyejfb7Y1ENqajXqZlRae/6V5lCOoJGW1Ff3V0gGoLI09It/f2R6W50DdvcEHfRp Fw== Received: from aserv0021.oracle.com (aserv0021.oracle.com [141.146.126.233]) by userp2130.oracle.com with ESMTP id 2n7ustu1rk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sun, 21 Oct 2018 16:15:08 +0000 Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserv0021.oracle.com (8.14.4/8.14.4) with ESMTP id w9LGF6oi007281 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sun, 21 Oct 2018 16:15:06 GMT Received: from abhmp0002.oracle.com (abhmp0002.oracle.com [141.146.116.8]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id w9LGF5Fk020887; Sun, 21 Oct 2018 16:15:05 GMT Received: from localhost (/10.159.225.70) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Sun, 21 Oct 2018 09:15:04 -0700 Subject: [PATCH v6 00/28] fs: fixes for serious clone/dedupe problems From: "Darrick J. Wong" To: david@fromorbit.com, darrick.wong@oracle.com Cc: sandeen@redhat.com, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, ocfs2-devel@oss.oracle.com Date: Sun, 21 Oct 2018 09:15:03 -0700 Message-ID: <154013850285.29026.16168387526580596209.stgit@magnolia> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9053 signatures=668683 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=913 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1810210151 Sender: linux-cifs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Hi all, Dave, Eric, and I have been chasing a stale data exposure bug in the XFS reflink implementation, and tracked it down to reflink forgetting to do some of the file-extending activities that must happen for regular writes. We then started auditing the clone, dedupe, and copyfile code and realized that from a file contents perspective, clonerange isn't any different from a regular file write. Unfortunately, we also noticed that *unlike* a regular write, clonerange skips a ton of overflow checks, such as validating the ranges against s_maxbytes, MAX_NON_LFS, and RLIMIT_FSIZE. We also observed that cloning into a file did not strip security privileges (suid, capabilities) like a regular write would. I also noticed that xfs and ocfs2 need to dump the page cache before remapping blocks, not after. In fixing the range checking problems I also realized that both dedupe and copyfile tell userspace how much of the requested operation was acted upon. Since the range validation can shorten a clone request (or we can ENOSPC midway through), we might as well plumb the short operation reporting back through the VFS indirection code to userspace. I added a few more cleanups to the xfs code per reviewer suggestions. So, here's the whole giant pile of patches[1] that fix all the problems. This branch is against current upstream (4.19-rc8). The patch "generic: test reflink side effects" recently sent to fstests exercises the fixes in this series. Tests are in [2]. --D [1] https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux.git/log/?h=djwong-devel [2] https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfstests-dev.git/log/?h=djwong-devel