diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index 68a9587c969..5abefb12891 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -859,6 +859,19 @@ int smp_sig_channel(struct l2cap_conn *conn, struct sk_buff *skb)
 
 	skb_pull(skb, sizeof(code));
 
+	/*
+	 * The SMP context must be initialized for all other PDUs except
+	 * pairing and security requests. If we get any other PDU when
+	 * not initialized simply disconnect (done if this function
+	 * returns an error).
+	 */
+	if (code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ &&
+	    !conn->smp_chan) {
+		BT_ERR("Unexpected SMP command 0x%02x. Disconnecting.", code);
+		kfree_skb(skb);
+		return -ENOTSUPP;
+	}
+
 	switch (code) {
 	case SMP_CMD_PAIRING_REQ:
 		reason = smp_cmd_pairing_req(conn, skb);