Most likely you will need to upgrade the entire kernel. The easiest way to do that is probably to install a newer version of Slackware.
If you really need your old Slackware 12.0 installation for something you might be able to create a disk image of your current installation and keep it alive in some virtual environment like qemu.
If your old Slackware 12.0 installation needs access to some hardware and not possible to virtualize, you might be able to compile some old version of qemu which works on Slackware 12, install a newer version of Slackware within a virtual machine running on Slackware 12.0. Give the virtual machine access to the USB device and make the virtual machine a router for your Slackware 12.0 machine.
However, it really seem better to upgrade to a version of Slackware that has not been End Of Life for more than 10 years. From
https://mirrors.slackware.com/slackw.../ChangeLog.txt :
Code:
####################################################################
# NOTICE OF INPENDING EOL (END OF LIFE) FOR OLD SLACKWARE VERSIONS #
# #
# Effective August 1, 2012, security patches will no longer be #
# provided for the following versions of Slackware (which will all #
# be more than 5 years old at that time): #
# Slackware 8.1, 9.0, 9.1, 10.0, 10.1, 10.2, 11.0, 12.0. #
# If you are still running these versions you should consider #
# migrating to a newer version (preferably as recent as possible). #
# Alternately, you may make arrangements to handle your own #
# security patches. If for some reason you are unable to upgrade #
# or handle your own security patches, limited security support #
# may be available for a fee. Inquire at security@slackware.com. #
####################################################################
regards Henrik