RE: nfsd vurlerability submit

Frank Filz
2021-01-13T15:46:22Z

> On Wed, Jan 13, 2021 at 03:16:52PM +0000, Trond Myklebust wrote:
> > How would that work then? Would you just look at the project ID of the
> > directory identified by the filehandle as the export point, and then
> > match to the project ID on the target inode? That sounds like it
> > doesn't even need to encode anything special in the filehandle.
>
> True, we would not even have to encode them.
>
> > How do you set a project ID in XFS?
>
> With the XFS_IOC_SETXFLAGS ioctl.
>
> On the command line side people usually do it using the xfs_quota tool as
part
> of setting up the tree quotas, but it can also be done separately using
the chproj
> subcommand of xfs_io.

Is this also queried via the ioctl? If this is a viable way of specifying
sub-trees, nfs-ganesha could also use it, though making an ioctl call for
each file system object would add some metadata performance hit.

Frank