On Mon, Jan 31, 2022 at 05:43:47PM +1100, Dave Chinner wrote:
> From: Dave Chinner <dchinner@xxxxxxxxxx>
>
> In XFS, we always update the inode change and modification time when
> any fallocate() operation succeeds. Furthermore, as various
> fallocate modes can change the file contents (extending EOF,
> punching holes, zeroing things, shifting extents), we should drop
> file privileges like suid just like we do for a regular write().
> There's already a VFS helper that figures all this out for us, so
> use that.
>
> The net effect of this is that we no longer drop suid/sgid if the
> caller is root, but we also now drop file capabilities.
>
> We also move the xfs_update_prealloc_flags() function so that it now
> is only called by the scope that needs to set the the prealloc flag.
>
> Based on a patch from Darrick Wong.
>
> Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx>
I think you can get rid of @flags entirely, right?
With that fixed, I think this looks good.
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
--D
> ---
> fs/xfs/xfs_file.c | 13 +++++++++----
> 1 file changed, 9 insertions(+), 4 deletions(-)
>
> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
> index 6eda41710a5a..223996822d84 100644
> --- a/fs/xfs/xfs_file.c
> +++ b/fs/xfs/xfs_file.c
> @@ -953,6 +953,10 @@ xfs_file_fallocate(
> goto out_unlock;
> }
>
> + error = file_modified(file);
> + if (error)
> + goto out_unlock;
> +
> if (mode & FALLOC_FL_PUNCH_HOLE) {
> error = xfs_free_file_space(ip, offset, len);
> if (error)
> @@ -1053,11 +1057,12 @@ xfs_file_fallocate(
> if (error)
> goto out_unlock;
> }
> - }
>
> - error = xfs_update_prealloc_flags(ip, flags);
> - if (error)
> - goto out_unlock;
> + error = xfs_update_prealloc_flags(ip, XFS_PREALLOC_SET);
> + if (error)
> + goto out_unlock;
> +
> + }
>
> /* Change file size if needed */
> if (new_size) {
> --
> 2.33.0
>
