Bluetooth: L2CAP: Fix using wrong mode

If user has a set to use SOCK_STREAM the socket would default to
L2CAP_MODE_ERTM which later needs to be adjusted if the destination
address is LE which doesn't support such mode.

Fixes: 15f02b91 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

net/bluetooth/l2cap_sock.c

@@ -161,7 +161,11 @@ static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen)
 		break;
 	}
 
-	if (chan->psm && bdaddr_type_is_le(chan->src_type))
+	/* Use L2CAP_MODE_LE_FLOWCTL (CoC) in case of LE address and
+	 * L2CAP_MODE_EXT_FLOWCTL (ECRED) has not been set.
+	 */
+	if (chan->psm && bdaddr_type_is_le(chan->src_type) &&
+	    chan->mode != L2CAP_MODE_EXT_FLOWCTL)
 		chan->mode = L2CAP_MODE_LE_FLOWCTL;
 
 	chan->state = BT_BOUND;
@@ -255,7 +259,11 @@ static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr,
 			return -EINVAL;
 	}
 
-	if (chan->psm && bdaddr_type_is_le(chan->src_type) && !chan->mode)
+	/* Use L2CAP_MODE_LE_FLOWCTL (CoC) in case of LE address and
+	 * L2CAP_MODE_EXT_FLOWCTL (ECRED) has not been set.
+	 */
+	if (chan->psm && bdaddr_type_is_le(chan->src_type) &&
+	    chan->mode != L2CAP_MODE_EXT_FLOWCTL)
 		chan->mode = L2CAP_MODE_LE_FLOWCTL;
 
 	l2cap_sock_init_pid(sk);