求教 laravel5.1 TokenMismatchException in VerifyCsrfToken.php line 53 错误

用户登录后,进入系统,因长时间放置,用户失效,中间件重定向到登录界面,再重新登录的时候抛异常TokenMismatchException,底层代码如下:

public function handle($request, Closure $next)
    {
        if ($this->isReading($request) || $this->shouldPassThrough($request) || $this->tokensMatch($request)) {
            return $this->addCookieToResponse($request, $next($request));
        }

        throw new TokenMismatchException;
    }