o The server has not recorded an unconfirmed { v, x, c, *, * } and has recorded a confirmed { v, x, c, *, s }. If the principals of the record and of SETCLIENTID_CONFIRM do not match, the server returns NFS4ERR_CLID_INUSE without removing any relevant leased client state, and without changing recorded callback and callback_ident values for client { x }. The current code intends to do what the spec describes above but it forgot to set 'old' to NULL resulting to the confirmed client to be expired. Fixes: 2b63482185e6 ("nfsd: fix clid_inuse on mount with security change") Signed-off-by: Dai Ngo <dai.ngo@xxxxxxxxxx> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> Reviewed-by: Bruce Fields <bfields@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/nfsd/nfs4state.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -3424,8 +3424,10 @@ nfsd4_setclientid_confirm(struct svc_rqs status = nfserr_clid_inuse; if (client_has_state(old) && !same_creds(&unconf->cl_cred, - &old->cl_cred)) + &old->cl_cred)) { + old = NULL; goto out; + } status = mark_client_expired_locked(old); if (status) { old = NULL; Patches currently in stable-queue which might be from dai.ngo@xxxxxxxxxx are queue-4.9/nfsd-nfsd4_setclientid_confirm-mistakenly-expires-confirmed-client.patch