Edite seu /etc/apt/sources.list
da seguinte forma:
deb http://httpredir.debian.org/debian jessie main contrib
deb-src http://httpredir.debian.org/debian jessie main contrib
deb http://httpredir.debian.org/debian jessie-updates main contrib
deb-src http://httpredir.debian.org/debian jessie-updates main contrib
deb http://security.debian.org/ jessie/updates main contrib
deb-src http://security.debian.org/ jessie/updates main contrib
Salve e execute o seguinte comando:
sudo apt-get update && sudo apt-get upgrade && sudo apt-get dist-upgrade
sudo apt-get install samba