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=-6.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,UNPARSEABLE_RELAY 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 C1EBDC4321A for ; Tue, 11 Jun 2019 04:48:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8F6A820820 for ; Tue, 11 Jun 2019 04:48:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="aajQA90v" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2403831AbfFKErx (ORCPT ); Tue, 11 Jun 2019 00:47:53 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:44470 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2403815AbfFKErw (ORCPT ); Tue, 11 Jun 2019 00:47:52 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x5B4hb7L159153; Tue, 11 Jun 2019 04:46:44 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : from : to : cc : date : message-id : in-reply-to : references : mime-version : content-type : content-transfer-encoding; s=corp-2018-07-02; bh=OE6FPPB5Pqi/Vl6YrpWW8Mgm59ZrawiJ1ASuvgj6hZQ=; b=aajQA90vj37ND50UtdyHx5H16e4znrHfLUb+wBHywGqmqqRsIos1xOgFYLz7aYNs00s1 mkdEqPk+9iThLFFbd7m84IB9UbTbiJsER4EGmYV30XNlH6n40JvOmYi8cKj93Y3wOIWS xXXEp1l5r1zAYgrHOMIuw78O9W4vf7dHoDzzlKM07X2NgjrlxKWaQ90Q6ZtGKszaDIiW t6S8su+95if8Mv8oeTvn/HimNYzwaiJe7JgUnemVyARWuXBfLDIzU5Dpew2Ysp6JC1dM Nh5hEvqL7jgmqANgt7EJvwjiQk/FOzixoiiL9QVfsDpehQuyb5PWlCJr/s6iVqc1Wuda mA== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by userp2130.oracle.com with ESMTP id 2t04etjkw1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 11 Jun 2019 04:46:43 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x5B4ipsN119991; Tue, 11 Jun 2019 04:46:43 GMT Received: from pps.reinject (localhost [127.0.0.1]) by aserp3030.oracle.com with ESMTP id 2t04hy50d3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 11 Jun 2019 04:46:43 +0000 Received: from aserp3030.oracle.com (aserp3030.oracle.com [127.0.0.1]) by pps.reinject (8.16.0.27/8.16.0.27) with SMTP id x5B4kgVr123729; Tue, 11 Jun 2019 04:46:42 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserp3030.oracle.com with ESMTP id 2t04hy50d0-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 11 Jun 2019 04:46:42 +0000 Received: from abhmp0009.oracle.com (abhmp0009.oracle.com [141.146.116.15]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id x5B4keoZ002792; Tue, 11 Jun 2019 04:46:40 GMT Received: from localhost (/67.169.218.210) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 10 Jun 2019 21:46:40 -0700 Subject: [PATCH 3/6] vfs: flush and wait for io when setting the immutable flag via FSSETXATTR From: "Darrick J. Wong" To: matthew.garrett@nebula.com, yuchao0@huawei.com, tytso@mit.edu, darrick.wong@oracle.com, ard.biesheuvel@linaro.org, josef@toxicpanda.com, clm@fb.com, adilger.kernel@dilger.ca, viro@zeniv.linux.org.uk, jack@suse.com, dsterba@suse.com, jaegeuk@kernel.org, jk@ozlabs.org Cc: reiserfs-devel@vger.kernel.org, linux-efi@vger.kernel.org, devel@lists.orangefs.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-xfs@vger.kernel.org, linux-mm@kvack.org, linux-nilfs@vger.kernel.org, linux-mtd@lists.infradead.org, ocfs2-devel@oss.oracle.com, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org Date: Mon, 10 Jun 2019 21:46:33 -0700 Message-ID: <156022839302.3227213.8773888198343223122.stgit@magnolia> In-Reply-To: <156022836912.3227213.13598042497272336695.stgit@magnolia> References: <156022836912.3227213.13598042497272336695.stgit@magnolia> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9284 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=2 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1906110033 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org From: Darrick J. Wong When we're using FS_IOC_FSSETXATTR to set the immutable flag on a file, we need to ensure that userspace can't continue to write the file after the file becomes immutable. To make that happen, we have to flush all the dirty pagecache pages to disk to ensure that we can fail a page fault on a mmap'd region, wait for pending directio to complete, and hope the caller locked out any new writes by holding the inode lock. Signed-off-by: Darrick J. Wong --- fs/btrfs/ioctl.c | 3 +++ fs/ext4/ioctl.c | 3 +++ fs/f2fs/file.c | 3 +++ fs/xfs/xfs_ioctl.c | 39 +++++++++++++++++++++++++++++++++------ include/linux/fs.h | 23 +++++++++++++++++++++++ 5 files changed, 65 insertions(+), 6 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index f431813b2454..63a9281e6ce0 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -432,6 +432,9 @@ static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg) __btrfs_ioctl_fsgetxattr(binode, &old_fa); ret = vfs_ioc_fssetxattr_check(inode, &old_fa, &fa); + if (ret) + goto out_unlock; + ret = vfs_ioc_fssetxattr_flush_data(inode, &fa); if (ret) goto out_unlock; diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index a05341b94d98..6037585c1520 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -1115,6 +1115,9 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) inode_lock(inode); ext4_fsgetxattr(inode, &old_fa); err = vfs_ioc_fssetxattr_check(inode, &old_fa, &fa); + if (err) + goto out; + err = vfs_ioc_fssetxattr_flush_data(inode, &fa); if (err) goto out; flags = (ei->i_flags & ~EXT4_FL_XFLAG_VISIBLE) | diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index d3cf4bdb8738..97f4bb36540f 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -2832,6 +2832,9 @@ static int f2fs_ioc_fssetxattr(struct file *filp, unsigned long arg) __f2fs_ioc_fsgetxattr(inode, &old_fa); err = vfs_ioc_fssetxattr_check(inode, &old_fa, &fa); + if (err) + goto out; + err = vfs_ioc_fssetxattr_flush_data(inode, &fa); if (err) goto out; flags = (fi->i_flags & ~F2FS_FL_XFLAG_VISIBLE) | diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index b494e7e881e3..88583b3e1e76 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -1014,6 +1014,28 @@ xfs_diflags_to_linux( #endif } +/* + * Lock the inode against file io and page faults, then flush all dirty pages + * and wait for writeback and direct IO operations to finish. Returns with + * the relevant inode lock flags set in @join_flags. Caller is responsible for + * unlocking even on error return. + */ +static int +xfs_ioctl_setattr_flush( + struct xfs_inode *ip, + int *join_flags) +{ + /* Already locked the inode from IO? Assume we're done. */ + if (((*join_flags) & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL)) == + (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL)) + return 0; + + /* Lock and flush all mappings and IO in preparation for flag change */ + *join_flags = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL; + xfs_ilock(ip, *join_flags); + return inode_flush_data(VFS_I(ip)); +} + static int xfs_ioctl_setattr_xflags( struct xfs_trans *tp, @@ -1099,23 +1121,22 @@ xfs_ioctl_setattr_dax_invalidate( if (!(fa->fsx_xflags & FS_XFLAG_DAX) && !IS_DAX(inode)) return 0; - if (S_ISDIR(inode->i_mode)) + if (!S_ISREG(inode->i_mode)) return 0; - /* lock, flush and invalidate mapping in preparation for flag change */ - xfs_ilock(ip, XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL); - error = filemap_write_and_wait(inode->i_mapping); + error = xfs_ioctl_setattr_flush(ip, join_flags); if (error) goto out_unlock; error = invalidate_inode_pages2(inode->i_mapping); if (error) goto out_unlock; - *join_flags = XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL; return 0; out_unlock: - xfs_iunlock(ip, XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL); + if (*join_flags) + xfs_iunlock(ip, *join_flags); + *join_flags = 0; return error; } @@ -1337,6 +1358,12 @@ xfs_ioctl_setattr( if (code) goto error_free_dquots; + if (!join_flags && vfs_ioc_fssetxattr_need_flush(VFS_I(ip), fa)) { + code = xfs_ioctl_setattr_flush(ip, &join_flags); + if (code) + goto error_free_dquots; + } + tp = xfs_ioctl_setattr_get_trans(ip, join_flags); if (IS_ERR(tp)) { code = PTR_ERR(tp); diff --git a/include/linux/fs.h b/include/linux/fs.h index 9c899c63957e..dae2b31cd32b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3584,5 +3584,28 @@ static inline int vfs_ioc_setflags_flush_data(struct inode *inode, int flags) int vfs_ioc_fssetxattr_check(struct inode *inode, const struct fsxattr *old_fa, struct fsxattr *fa); +/* + * Do we need to flush the file data before changing attributes? When we're + * setting the immutable flag we must stop all directio writes and flush the + * dirty pages so that we can fail the page fault on the next write attempt. + */ +static inline bool vfs_ioc_fssetxattr_need_flush(struct inode *inode, + struct fsxattr *fa) +{ + if (S_ISREG(inode->i_mode) && !IS_IMMUTABLE(inode) && + (fa->fsx_xflags & FS_XFLAG_IMMUTABLE)) + return true; + + return false; +} + +/* Flush file data before changing attributes, if necessary. */ +static inline int vfs_ioc_fssetxattr_flush_data(struct inode *inode, + struct fsxattr *fa) +{ + if (vfs_ioc_fssetxattr_need_flush(inode, fa)) + return inode_flush_data(inode); + return 0; +} #endif /* _LINUX_FS_H */