Re: [PATCH 2/2] vfs: dedupe should return EPERM if permission is not granted

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Fri, May 11, 2018 at 12:26:51PM -0700, Mark Fasheh wrote:
> Right now we return EINVAL if a process does not have permission to dedupe a
> file. This was an oversight on my part. EPERM gives a true description of
> the nature of our error, and EINVAL is already used for the case that the
> filesystem does not support dedupe.
> 
> Signed-off-by: Mark Fasheh <mfasheh@suse.de>
> ---
>  fs/read_write.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/read_write.c b/fs/read_write.c
> index 77986a2e2a3b..8edef43a182c 100644
> --- a/fs/read_write.c
> +++ b/fs/read_write.c
> @@ -2038,7 +2038,7 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
>  			info->status = -EINVAL;
>  		} else if (!(is_admin || (dst_file->f_mode & FMODE_WRITE) ||
>  			     uid_eq(current_fsuid(), dst->i_uid))) {
> -			info->status = -EINVAL;
> +			info->status = -EPERM;

Hmm, are we allowed to change this aspect of the kabi after the fact?

Granted, we're only trading one error code for another, but will the
existing users of this care?  xfs_io won't and I assume duperemove won't
either, but what about bees? :)

--D

>  		} else if (file->f_path.mnt != dst_file->f_path.mnt) {
>  			info->status = -EXDEV;
>  		} else if (S_ISDIR(dst->i_mode)) {
> -- 
> 2.15.1
>