diff --git a/[refs] b/[refs]
index 6892b0ace0e7..a723b69aed89 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ac6721a13e5b1a90728e790600f827a5e5f5da2f
+refs/heads/master: a62573dc353b255dbbc8520bfdcb1c8a8c1ada87
diff --git a/trunk/fs/nfsd/nfs4state.c b/trunk/fs/nfsd/nfs4state.c
index fbde6f79922e..6dbaa379c863 100644
--- a/trunk/fs/nfsd/nfs4state.c
+++ b/trunk/fs/nfsd/nfs4state.c
@@ -1515,6 +1515,9 @@ nfsd4_create_session(struct svc_rqst *rqstp,
 	bool confirm_me = false;
 	int status = 0;
 
+	if (cr_ses->flags & ~SESSION4_FLAG_MASK_A)
+		return nfserr_inval;
+
 	nfs4_lock_state();
 	unconf = find_unconfirmed_client(&cr_ses->clientid);
 	conf = find_confirmed_client(&cr_ses->clientid);
diff --git a/trunk/include/linux/nfs4.h b/trunk/include/linux/nfs4.h
index b528f6d4b860..8937727e7039 100644
--- a/trunk/include/linux/nfs4.h
+++ b/trunk/include/linux/nfs4.h
@@ -570,9 +570,11 @@ struct nfs4_sessionid {
 };
 
 /* Create Session Flags */
-#define SESSION4_PERSIST	 0x001
-#define SESSION4_BACK_CHAN 	 0x002
-#define SESSION4_RDMA		 0x004
+#define SESSION4_PERSIST	0x001
+#define SESSION4_BACK_CHAN	0x002
+#define SESSION4_RDMA		0x004
+
+#define SESSION4_FLAG_MASK_A	0x007
 
 enum state_protect_how4 {
 	SP4_NONE	= 0,