Re: [PATCH] xfs: add missing error check in xfs_prepare_shift()

[Allison Henderson <allison.henderson@oracle.com>]

Looks ok to me.  You can add my review:

Reviewed-by: Allison Collins <allison.henderson@oracle.com>

On 4/26/19 5:06 AM, Brian Foster wrote:
> xfs_prepare_shift() fails to check the error return from
> xfs_flush_unmap_range(). If the latter fails, that could lead to an
> insert/collapse range operation over a delalloc range, which is not
> supported.
> 
> Add an error check and return appropriately. This is reproduced
> rarely by generic/475.
> 
> Signed-off-by: Brian Foster <bfoster@redhat.com>
> ---
>   fs/xfs/xfs_bmap_util.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
> index 2db43ff4f8b5..06d07f1e310b 100644
> --- a/fs/xfs/xfs_bmap_util.c
> +++ b/fs/xfs/xfs_bmap_util.c
> @@ -1193,6 +1193,8 @@ xfs_prepare_shift(
>   	 * about to shift down every extent from offset to EOF.
>   	 */
>   	error = xfs_flush_unmap_range(ip, offset, XFS_ISIZE(ip));
> +	if (error)
> +		return error;
>   
>   	/*
>   	 * Clean out anything hanging around in the cow fork now that
>