diff mbox series

[03/29] vfs: exit early from zero length remap operations

Message ID	153981627600.5568.16857314567554014035.stgit@magnolia (mailing list archive)
State	New, archived
Headers	show Return-Path: <linux-fsdevel-owner@kernel.org> Subject: [PATCH 03/29] vfs: exit early from zero length remap operations From: "Darrick J. Wong" <darrick.wong@oracle.com> 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, Christoph Hellwig <hch@lst.de>, ocfs2-devel@oss.oracle.com Date: Wed, 17 Oct 2018 15:44:36 -0700 Message-ID: <153981627600.5568.16857314567554014035.stgit@magnolia> In-Reply-To: <153981625504.5568.2708520119290577378.stgit@magnolia> References: <153981625504.5568.2708520119290577378.stgit@magnolia> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk
Series	fs: fixes for serious clone/dedupe problems \| expand [v6,00/29] fs: fixes for serious clone/dedupe problems [01/29] vfs: vfs_clone_file_prep_inodes should return EINVAL for a clone from beyond EOF [02/29] vfs: check file ranges before cloning files [03/29] vfs: exit early from zero length remap operations [04/29] vfs: strengthen checking of file range inputs to generic_remap_checks [05/29] vfs: avoid problematic remapping requests into partial EOF block [06/29] vfs: skip zero-length dedupe requests [07/29] vfs: rename vfs_clone_file_prep to be more descriptive [08/29] vfs: rename clone_verify_area to remap_verify_area [09/29] vfs: combine the clone and dedupe into a single remap_file_range [10/29] vfs: pass remap flags to generic_remap_file_range_prep [11/29] vfs: pass remap flags to generic_remap_checks [12/29] vfs: remap helper should update destination inode metadata [13/29] vfs: make remap_file_range functions take and return bytes completed [14/29] vfs: plumb remap flags through the vfs clone functions [15/29] vfs: plumb remap flags through the vfs dedupe functions [16/29] vfs: enable remap callers that can handle short operations [17/29] vfs: hide file range comparison function [18/29] vfs: clean up generic_remap_file_range_prep return value [19/29] ocfs2: truncate page cache for clone destination file before remapping [20/29] ocfs2: fix pagecache truncation prior to reflink [21/29] ocfs2: support partial clone range and dedupe range [22/29] ocfs2: remove ocfs2_reflink_remap_range [23/29] xfs: add a per-xfs trace_printk macro [24/29] xfs: fix pagecache truncation prior to reflink [25/29] xfs: clean up xfs_reflink_remap_blocks call site [26/29] xfs: support returning partial reflink results [27/29] xfs: remove redundant remap partial EOF block checks [28/29] xfs: remove xfs_reflink_remap_range [29/29] xfs: remove [cm]time update from reflink calls

Commit Message

Darrick J. Wong Oct. 17, 2018, 10:44 p.m. UTC

From: Darrick J. Wong <darrick.wong@oracle.com>

If a remap caller asks us to remap to the source file's EOF and the
source file length leaves us with a zero byte request, exit early.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 fs/read_write.c |    2 ++
 1 file changed, 2 insertions(+)

diff mbox series

Patch

diff --git a/fs/read_write.c b/fs/read_write.c
index d6e8e242a15f..2456da3f8a41 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1748,6 +1748,8 @@  int vfs_clone_file_prep(struct file *file_in, loff_t pos_in,
 		if (pos_in > isize)
 			return -EINVAL;
 		*len = isize - pos_in;
+		if (*len == 0)
+			return 0;
 	}
 
 	/* Check that we don't violate system file offset limits. */