diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index 8c225ef349cd..2ac8d50861e0 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -32,6 +32,8 @@
 
 #define SMP_TIMEOUT	msecs_to_jiffies(30000)
 
+#define AUTH_REQ_MASK   0x07
+
 static inline void swap128(u8 src[16], u8 dst[16])
 {
 	int i;
@@ -230,7 +232,7 @@ static void build_pairing_cmd(struct l2cap_conn *conn,
 		req->max_key_size = SMP_MAX_ENC_KEY_SIZE;
 		req->init_key_dist = 0;
 		req->resp_key_dist = dist_keys;
-		req->auth_req = authreq;
+		req->auth_req = (authreq & AUTH_REQ_MASK);
 		return;
 	}
 
@@ -239,7 +241,7 @@ static void build_pairing_cmd(struct l2cap_conn *conn,
 	rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
 	rsp->init_key_dist = 0;
 	rsp->resp_key_dist = req->resp_key_dist & dist_keys;
-	rsp->auth_req = authreq;
+	rsp->auth_req = (authreq & AUTH_REQ_MASK);
 }
 
 static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)