Re: [PATCH 0/2] nfsd/nfsdctl: default to starting with v4.0 servers disabled

Jeff Layton
2026-03-22T21:42:32Z

On Sun, 2026-03-22 at 22:31 +0100, Salvatore Bonaccorso wrote:
> Hi Steve, Jeff,
>
> On Sun, Mar 22, 2026 at 04:30:02PM -0400, Steve Dickson wrote:
> >
> >
> > On 10/8/25 4:13 PM, Jeff Layton wrote:
> > > At this week's NFS Bakeathon, we had a discussion around deprecating the
> > > NFSv4.0 protocol. To prepare for that eventuality, make the NFS server
> > > only accept NFSv4.0 if it was explicitly requested in the config file or
> > > in command-line options.
> > >
> > > Signed-off-by: Jeff Layton <jlayton@kernel.org>
> > > ---
> > > Jeff Layton (2):
> > > nfsd: disable v4.0 by default
> > > nfsdctl: disable v4.0 by default
> > >
> > > utils/nfsd/nfsd.c | 5 +++--
> > > utils/nfsdctl/nfsdctl.c | 2 +-
> > > 2 files changed, 4 insertions(+), 3 deletions(-)
> > > ---
> > > base-commit: 612e407c46b848932c32be00b835a7b5317e3d08
> > > change-id: 20251008-master-724587cca99a
> > >
> > > Best regards,
> > Committed... (tag: nfs-utils-2-9-1-rc1)
> >
> > My apologies for taking so long... The CVE
> > took longer than expected and there was
> > some issues with recent patches,
> > which caused another release..
> >
> > Turning off a protocol version (v4.0)
> > on the server by default which this rc
> > release does, is not a small thing
> > although with the 7.X kernels the
> > v4.0 client is already off.
>
> I have one small followup question on that. The nfs.conf reads:
>
> [nfsd]
> # debug=0
> # threads=16
> # host=
> # port=0
> # grace-time=90
> # lease-time=90
> # udp=n
> # tcp=y
> # vers3=y
> # vers4=y
> # vers4.0=y
> # vers4.1=y
> # vers4.2=y
> [...]
>
> Should the 'default off' change as well be reflected in the commented
> entry for vers4.0 and read vers4.0=n for consistency?
>

Yes, good catch. Would you mind spinning up a patch? If not, I'll do
one in the near future.
--
Jeff Layton <jlayton@kernel.org>