Bluetooth: Call L2CAP teardown callback before clearing chan->conn

L2CAP channel implementations may want to still access the chan->conn
pointer. This will particularly be the case for SMP that will want to
clear a reference to the SMP channel in the l2cap_conn structure. The
only user of the teardown callback so far is l2cap_sock.c and for the
code there it makes no difference whether the callback is called before
or after clearing the chan->conn pointer.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

net/bluetooth/l2cap_core.c

@@ -566,6 +566,8 @@ void l2cap_chan_del(struct l2cap_chan *chan, int err)
 
 	BT_DBG("chan %p, conn %p, err %d", chan, conn, err);
 
+	chan->ops->teardown(chan, err);
+
 	if (conn) {
 		struct amp_mgr *mgr = conn->hcon->amp_mgr;
 		/* Delete from channel list */
@@ -589,8 +591,6 @@ void l2cap_chan_del(struct l2cap_chan *chan, int err)
 		amp_disconnect_logical_link(hs_hchan);
 	}
 
-	chan->ops->teardown(chan, err);
-
 	if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
 		return;