sudo apt-get update
sudo apt-get install linux-headers-generic build-essential dkms
sudo apt-get install linux-source
sudo apt-get install --reinstall bcmwl-kernel-source
apt-get install --reinstall bcmwl-kernel-source Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package bcmwl-kernel-source
sudo modprobe wl
sudo dpkg -i wireless-bcm43142-dkms_6.20.55.19-1_amd64.deb
apt install broadcom-sta-dkms
apt install broadcom-sta-dkms Reading package lists... Done Building dependency tree Reading state information... Done broadcom-sta-dkms is already the newest version (6.30.223.248-3). 0 upgraded, 0 newly installed, 0 to remove and 98 not upgraded.
原文：https://www.cnblogs.com/winditsway/p/12483805.html