From patchwork Mon Feb 15 15:43:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 12088433 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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY 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 3AF1CC433DB for ; Mon, 15 Feb 2021 15:44:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0C24264E8E for ; Mon, 15 Feb 2021 15:44:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231510AbhBOPok (ORCPT ); Mon, 15 Feb 2021 10:44:40 -0500 Received: from mx2.suse.de ([195.135.220.15]:49476 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231584AbhBOPng (ORCPT ); Mon, 15 Feb 2021 10:43:36 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 616CCADE0; Mon, 15 Feb 2021 15:42:17 +0000 (UTC) Received: from localhost (brahms [local]) by brahms (OpenSMTPD) with ESMTPA id 69cb18b7; Mon, 15 Feb 2021 15:43:19 +0000 (UTC) From: Luis Henriques To: Amir Goldstein , Jeff Layton , Steve French , Miklos Szeredi , Trond Myklebust , Anna Schumaker , Alexander Viro , "Darrick J. Wong" , Dave Chinner , Greg KH , Nicolas Boichat , Ian Lance Taylor , Luis Lozano Cc: ceph-devel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, Luis Henriques Subject: [PATCH v2] vfs: prevent copy_file_range to copy across devices Date: Mon, 15 Feb 2021 15:43:17 +0000 Message-Id: <20210215154317.8590-1-lhenriques@suse.de> In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org Nicolas Boichat reported an issue when trying to use the copy_file_range syscall on a tracefs file. It failed silently because the file content is generated on-the-fly (reporting a size of zero) and copy_file_range needs to know in advance how much data is present. This commit restores the cross-fs restrictions that existed prior to 5dae222a5ff0 ("vfs: allow copy_file_range to copy across devices") and removes generic_copy_file_range() calls from ceph, cifs, fuse, and nfs. Fixes: 5dae222a5ff0 ("vfs: allow copy_file_range to copy across devices") Link: https://lore.kernel.org/linux-fsdevel/20210212044405.4120619-1-drinkcat@chromium.org/ Cc: Nicolas Boichat Signed-off-by: Luis Henriques Reviewed-by: Amir Goldstein Reviewed-by: Christoph Hellwig --- Changes since v1 (after Amir review) - restored do_copy_file_range() helper - return -EOPNOTSUPP if fs doesn't implement CFR - updated commit description fs/ceph/file.c | 21 +++----------------- fs/cifs/cifsfs.c | 3 --- fs/fuse/file.c | 21 +++----------------- fs/nfs/nfs4file.c | 20 +++---------------- fs/read_write.c | 49 ++++++++++------------------------------------ include/linux/fs.h | 3 --- 6 files changed, 19 insertions(+), 98 deletions(-) diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 209535d5b8d3..639bd7bfaea9 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -2261,9 +2261,9 @@ static ssize_t ceph_do_objects_copy(struct ceph_inode_info *src_ci, u64 *src_off return bytes; } -static ssize_t __ceph_copy_file_range(struct file *src_file, loff_t src_off, - struct file *dst_file, loff_t dst_off, - size_t len, unsigned int flags) +static ssize_t ceph_copy_file_range(struct file *src_file, loff_t src_off, + struct file *dst_file, loff_t dst_off, + size_t len, unsigned int flags) { struct inode *src_inode = file_inode(src_file); struct inode *dst_inode = file_inode(dst_file); @@ -2456,21 +2456,6 @@ static ssize_t __ceph_copy_file_range(struct file *src_file, loff_t src_off, return ret; } -static ssize_t ceph_copy_file_range(struct file *src_file, loff_t src_off, - struct file *dst_file, loff_t dst_off, - size_t len, unsigned int flags) -{ - ssize_t ret; - - ret = __ceph_copy_file_range(src_file, src_off, dst_file, dst_off, - len, flags); - - if (ret == -EOPNOTSUPP || ret == -EXDEV) - ret = generic_copy_file_range(src_file, src_off, dst_file, - dst_off, len, flags); - return ret; -} - const struct file_operations ceph_file_fops = { .open = ceph_open, .release = ceph_release, diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index ab883e84e116..7aa3d20f21c0 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -1229,9 +1229,6 @@ static ssize_t cifs_copy_file_range(struct file *src_file, loff_t off, len, flags); free_xid(xid); - if (rc == -EOPNOTSUPP || rc == -EXDEV) - rc = generic_copy_file_range(src_file, off, dst_file, - destoff, len, flags); return rc; } diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 8cccecb55fb8..0dd703278e49 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -3330,9 +3330,9 @@ static long fuse_file_fallocate(struct file *file, int mode, loff_t offset, return err; } -static ssize_t __fuse_copy_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, - size_t len, unsigned int flags) +static ssize_t fuse_copy_file_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + size_t len, unsigned int flags) { struct fuse_file *ff_in = file_in->private_data; struct fuse_file *ff_out = file_out->private_data; @@ -3439,21 +3439,6 @@ static ssize_t __fuse_copy_file_range(struct file *file_in, loff_t pos_in, return err; } -static ssize_t fuse_copy_file_range(struct file *src_file, loff_t src_off, - struct file *dst_file, loff_t dst_off, - size_t len, unsigned int flags) -{ - ssize_t ret; - - ret = __fuse_copy_file_range(src_file, src_off, dst_file, dst_off, - len, flags); - - if (ret == -EOPNOTSUPP || ret == -EXDEV) - ret = generic_copy_file_range(src_file, src_off, dst_file, - dst_off, len, flags); - return ret; -} - static const struct file_operations fuse_file_operations = { .llseek = fuse_file_llseek, .read_iter = fuse_file_read_iter, diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index 57b3821d975a..60998209e310 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -133,9 +133,9 @@ nfs4_file_flush(struct file *file, fl_owner_t id) } #ifdef CONFIG_NFS_V4_2 -static ssize_t __nfs4_copy_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, - size_t count, unsigned int flags) +static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + size_t count, unsigned int flags) { struct nfs42_copy_notify_res *cn_resp = NULL; struct nl4_server *nss = NULL; @@ -189,20 +189,6 @@ static ssize_t __nfs4_copy_file_range(struct file *file_in, loff_t pos_in, return ret; } -static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, - size_t count, unsigned int flags) -{ - ssize_t ret; - - ret = __nfs4_copy_file_range(file_in, pos_in, file_out, pos_out, count, - flags); - if (ret == -EOPNOTSUPP || ret == -EXDEV) - ret = generic_copy_file_range(file_in, pos_in, file_out, - pos_out, count, flags); - return ret; -} - static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence) { loff_t ret; diff --git a/fs/read_write.c b/fs/read_write.c index 75f764b43418..b217cd62ae0d 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1358,40 +1358,12 @@ COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, } #endif -/** - * generic_copy_file_range - copy data between two files - * @file_in: file structure to read from - * @pos_in: file offset to read from - * @file_out: file structure to write data to - * @pos_out: file offset to write data to - * @len: amount of data to copy - * @flags: copy flags - * - * This is a generic filesystem helper to copy data from one file to another. - * It has no constraints on the source or destination file owners - the files - * can belong to different superblocks and different filesystem types. Short - * copies are allowed. - * - * This should be called from the @file_out filesystem, as per the - * ->copy_file_range() method. - * - * Returns the number of bytes copied or a negative error indicating the - * failure. - */ - -ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, - size_t len, unsigned int flags) -{ - return do_splice_direct(file_in, &pos_in, file_out, &pos_out, - len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0); -} -EXPORT_SYMBOL(generic_copy_file_range); - static ssize_t do_copy_file_range(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, size_t len, unsigned int flags) { + ssize_t ret = -EXDEV; + /* * Although we now allow filesystems to handle cross sb copy, passing * a file of the wrong filesystem type to filesystem driver can result @@ -1400,14 +1372,14 @@ static ssize_t do_copy_file_range(struct file *file_in, loff_t pos_in, * several different file_system_type structures, but they all end up * using the same ->copy_file_range() function pointer. */ - if (file_out->f_op->copy_file_range && - file_out->f_op->copy_file_range == file_in->f_op->copy_file_range) - return file_out->f_op->copy_file_range(file_in, pos_in, - file_out, pos_out, - len, flags); + if (!file_out->f_op->copy_file_range) + ret = -EOPNOTSUPP; + else if (file_out->f_op->copy_file_range == file_in->f_op->copy_file_range) + ret = file_out->f_op->copy_file_range(file_in, pos_in, + file_out, pos_out, + len, flags); - return generic_copy_file_range(file_in, pos_in, file_out, pos_out, len, - flags); + return ret; } /* @@ -1514,8 +1486,7 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, } ret = do_copy_file_range(file_in, pos_in, file_out, pos_out, len, - flags); - WARN_ON_ONCE(ret == -EOPNOTSUPP); + flags); done: if (ret > 0) { fsnotify_access(file_in); diff --git a/include/linux/fs.h b/include/linux/fs.h index fd47deea7c17..3aaf627be409 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1910,9 +1910,6 @@ extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *); extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *); extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *, loff_t, size_t, unsigned int); -extern ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, - size_t len, unsigned int flags); extern int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, loff_t *count,