Re: [PATCH] nfsd: Remove incorrect check in nfsd4_validate_stateid

[Jeff Layton <jlayton@kernel.org>]

On Tue, 2023-07-18 at 08:38 -0400, trondmy@kernel.org wrote:
> From: Trond Myklebust <trond.myklebust@hammerspace.com>
> 
> If the client is calling TEST_STATEID, then it is because some event
> occurred that requires it to check all the stateids for validity and
> call FREE_STATEID on the ones that have been revoked. In this case,
> either the stateid exists in the list of stateids associated with that
> nfs4_client, in which case it should be tested, or it does not. There
> are no additional conditions to be considered.
> 
> Reported-by: Frank Ch. Eigler <fche@redhat.com>
> Fixes: 663e36f07666 ("nfsd4: kill warnings on testing stateids with mismatched clientids")
> Cc: stable@vger.kernel.org
> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
> ---
>  fs/nfsd/nfs4state.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 6e61fa3acaf1..3aefbad4cc09 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -6341,8 +6341,6 @@ static __be32 nfsd4_validate_stateid(struct nfs4_client *cl, stateid_t *stateid)
>  	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid) ||
>  		CLOSE_STATEID(stateid))
>  		return status;
> -	if (!same_clid(&stateid->si_opaque.so_clid, &cl->cl_clientid))
> -		return status;
>  	spin_lock(&cl->cl_lock);
>  	s = find_stateid_locked(cl, stateid);
>  	if (!s)

IDGI. Is this fixing an actual bug? Granted this code does seem
unnecessary, but removing it doesn't seem like it will cause any
user-visible change in behavior. Am I missing something?
-- 
Jeff Layton <jlayton@kernel.org>