NFSv4.1: Clear the old state by our client id before establishing a new lease

If the call to exchange-id returns with the EXCHGID4_FLAG_CONFIRMED_R flag
set, then that means our lease was established by a previous mount instance.
Ensure that we detect this situation, and that we clear the state held by
that mount.

Reported-by: Jorge Mora <Jorge.Mora@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

3 files changed, 17 insertions, 5 deletions

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 732526e04cd5..627f37c44456 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -6897,9 +6897,13 @@ static int _nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred,
 
         if (status == 0) {
                 clp->cl_clientid = res.clientid;
-                clp->cl_exchange_flags = (res.flags & ~EXCHGID4_FLAG_CONFIRMED_R);
-                if (!(res.flags & EXCHGID4_FLAG_CONFIRMED_R))
+                clp->cl_exchange_flags = res.flags;
+                /* Client ID is not confirmed */
+                if (!(res.flags & EXCHGID4_FLAG_CONFIRMED_R)) {
+                        clear_bit(NFS4_SESSION_ESTABLISHED,
+                                        &clp->cl_session->session_state);
                         clp->cl_seqid = res.seqid;
+                }
 
                 kfree(clp->cl_serverowner);
                 clp->cl_serverowner = res.server_owner;
@@ -7231,6 +7235,9 @@ static void nfs4_update_session(struct nfs4_session *session,
                 struct nfs41_create_session_res *res)
 {
         nfs4_copy_sessionid(&session->sess_id, &res->sessionid);
+        /* Mark client id and session as being confirmed */
+        session->clp->cl_exchange_flags |= EXCHGID4_FLAG_CONFIRMED_R;
+        set_bit(NFS4_SESSION_ESTABLISHED, &session->session_state);
         session->flags = res->flags;
         memcpy(&session->fc_attrs, &res->fc_attrs, sizeof(session->fc_attrs));
         if (res->flags & SESSION4_BACK_CHAN)
@@ -7326,8 +7333,8 @@ int nfs4_proc_destroy_session(struct nfs4_session *session,
         dprintk("--> nfs4_proc_destroy_session\n");
 
         /* session is still being setup */
-        if (session->clp->cl_cons_state != NFS_CS_READY)
-                return status;
+        if (!test_and_clear_bit(NFS4_SESSION_ESTABLISHED, &session->session_state))
+                return 0;
 
         status = rpc_call_sync(session->clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
         trace_nfs4_destroy_session(session->clp, status);
diff --git a/fs/nfs/nfs4session.h b/fs/nfs/nfs4session.h
index fc46c7455898..e3ea2c5324d6 100644
--- a/fs/nfs/nfs4session.h
+++ b/fs/nfs/nfs4session.h
@@ -70,6 +70,7 @@ struct nfs4_session {
 
 enum nfs4_session_state {
         NFS4_SESSION_INITING,
+        NFS4_SESSION_ESTABLISHED,
 };
 
 extern int nfs4_setup_slot_table(struct nfs4_slot_table *tbl,
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index d8b43f0e08fc..f95e3b58bbc3 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -353,7 +353,11 @@ int nfs41_discover_server_trunking(struct nfs_client *clp,
         if (clp != *result)
                 return 0;
 
-        set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
+        /* Purge state if the client id was established in a prior instance */
+        if (clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R)
+                set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
+        else
+                set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
         nfs4_schedule_state_manager(clp);
         status = nfs_wait_client_init_complete(clp);
         if (status < 0)