Bluetooth: L2CAP: Fix possible multiple reject send

In case of an incomplete command or a command with a null identifier 2
reject packets will be sent, one with the identifier and one with 0.
Consuming the data of the command will prevent it.
This allows to send a reject packet for each corrupted command in a
multi-command packet.

Signed-off-by: Frédéric Danis <[email protected]>
Signed-off-by: Luiz Augusto von Dentz <[email protected]>

Author: fdanis-oss

net/bluetooth/l2cap_core.c

@@ -6526,7 +6526,8 @@ static inline void l2cap_sig_channel(struct l2cap_conn *conn,
 		if (len > skb->len || !cmd->ident) {
 			BT_DBG("corrupted command");
 			l2cap_sig_send_rej(conn, cmd->ident);
-			break;
+			skb_pull(skb, len > skb->len ? skb->len : len);
+			continue;
 		}
 
 		err = l2cap_bredr_sig_cmd(conn, cmd, len, skb->data);