NFSv4.1: Fix the CREATE_SESSION slot number accounting

commit b519d408ea32040b1c7e10b155a3ee9a36660947 upstream.

Ensure that we conform to the algorithm described in RFC5661, section
18.36.4 for when to bump the sequence id. In essence we do it for all
cases except when the RPC call timed out, or in case of the server returning
NFS4ERR_DELAY or NFS4ERR_STALE_CLIENTID.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 7796beacdefb74097477204d9a39c8dc9d091c92..e2320c6431073a1e3c9a5d3866b919f6e190f1d3 100644 (file)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7509,12 +7509,20 @@ static int _nfs4_proc_create_session(struct nfs_client *clp,
        status = rpc_call_sync(session->clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
        trace_nfs4_create_session(clp, status);
 
+       switch (status) {
+       case -NFS4ERR_STALE_CLIENTID:
+       case -NFS4ERR_DELAY:
+       case -ETIMEDOUT:
+       case -EACCES:
+       case -EAGAIN:
+               goto out;
+       };
+
+       clp->cl_seqid++;
        if (!status) {
                /* Verify the session's negotiated channel_attrs values */
                status = nfs4_verify_channel_attrs(&args, &res);
                /* Increment the clientid slot sequence id */
-               if (clp->cl_seqid == res.seqid)
-                       clp->cl_seqid++;
                if (status)
                        goto out;
                nfs4_update_session(session, &res);