From: "Darrick J. Wong" <darrick.wong@xxxxxxxxxx> commit 3af423b03435c81036fa710623d3ae92fbe346a3 upstream. When we perform an finsert/fcollapse operation, cancel all the CoW extents for the affected file offset range so that they don't end up pointing to the wrong blocks. Reported-by: Amir Goldstein <amir73il@xxxxxxxxx> Reviewed-by: Carlos Maiolino <cmaiolino@xxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> --- fs/xfs/xfs_bmap_util.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 5ffefac081f7..5fccf9811e66 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -1445,7 +1445,19 @@ xfs_shift_file_space( return error; /* - * The extent shiting code works on extent granularity. So, if + * Clean out anything hanging around in the cow fork now that + * we've flushed all the dirty data out to disk to avoid having + * CoW extents at the wrong offsets. + */ + if (xfs_is_reflink_inode(ip)) { + error = xfs_reflink_cancel_cow_range(ip, offset, NULLFILEOFF, + true); + if (error) + return error; + } + + /* + * The extent shifting code works on extent granularity. So, if * stop_fsb is not the starting block of extent, we need to split * the extent at stop_fsb. */ -- 2.14.2