Inahltsverzeichnis eine Zeile zu lang

[eng1n3_17]

\documentclass[a4paper,12pt,twoside]{book}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}

\usepackage[ngerman]{babel}

\usepackage{amssymb,amsmath,amsthm}
\usepackage{braket,dsfont}
\usepackage{enumitem}
\usepackage{graphicx}



\usepackage[pagebackref]{hyperref}
\usepackage{fancyhdr}
\pagestyle{fancy}




\setlength{\headheight}{16pt}

\usepackage[left=3cm,right=2cm,bottom=3cm,top=3cm]{geometry}

\renewcommand{\headrulewidth}{0.4pt}
\begin{document}
\tableofcontents

\chapter{x}
\section{x} 
\section{x}

\chapter{x} 
\section{x}
\section{x}
\section{x}

\chapter{x}
\section{x} 
\subsection{x}
\subsection{xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx\\ xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx}
\subsection{xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx\\ xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx}
\section{xn} 

\chapter{x} 
\section{x}
\subsection{x}
\subsection{x}
\section{x}

\chapter{x}
\section{x}
\subsection{xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx\\ xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx}
\subsection{xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx\\ xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx}
\subsection{xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx\\ xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx}
\subsection{x}
\subsection{x}
 
\chapter{fazit}
\chapter{lit.-verz.}

\end{document}