sudo apt-get install bcmwl-kernel-source
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
  bcmwl-kernel-source
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B/1,150 kB of archives.
After this operation, 3,120 kB of additional disk space will be used.
Selecting previously unselected package bcmwl-kernel-source.
(Reading database ... 179844 files and directories currently installed.)
Unpacking bcmwl-kernel-source (from .../bcmwl-kernel-source_5.100.82.112+bdcom-0ubuntu3_i386.deb) ...
Setting up bcmwl-kernel-source (5.100.82.112+bdcom-0ubuntu3) ...
Loading new bcmwl-5.100.82.112+bdcom DKMS files...
Building only for 3.5.0-27-generic
Building for architecture i686
Building initial module for 3.5.0-27-generic
Done.

wl:
Running module version sanity check.
 - Original module
   - No original module exists within this kernel
 - Installation
   - Installing to /lib/modules/3.5.0-27-generic/updates/dkms/

depmod.................

DKMS: install completed.
ERROR: Module b43 does not exist in /proc/modules
ERROR: Module b43legacy does not exist in /proc/modules
ERROR: Module ssb is in use by ssb_hcd,b44
ERROR: Module bcm43xx does not exist in /proc/modules
ERROR: Module brcm80211 does not exist in /proc/modules
ERROR: Module brcmfmac does not exist in /proc/modules
ERROR: Module brcmsmac does not exist in /proc/modules
ERROR: Module bcma does not exist in /proc/modules
update-initramfs: deferring update (trigger activated)
Processing triggers for initramfs-tools ...
update-initramfs: Generating /boot/initrd.img-3.5.0-27-generic