🚀 go-pugleaf

Erik de Castro Lopo wrote:
> 
> David. E. Goble wrote:
> >
> > Hi All;
> >
> > I do not understand, how can a software program in RAM destory
> > hardware and data in ROM/PROM???
> > --Regards :                David. E. Goble
> >                            goble@kin.on.net
> 
> It can do this because the BIOS is stored in EEPROM : Electrically
> Erasable Programmable Read Only Memory. This particular virus
> erases the BIOS.

Even though this is a technically correct answer, I'd still say that any
PC which allows _all_ of the BIOS to be erased was designed to fail:

IMHO the only proper way to handle this is to logically split the bios
in two parts, where the first resides in a permanently write-protected
part of the eeprom. amd the second can be modified:

The first part contains enough of the startup code to enable booting
from a floppy, which can then contain a program to reload a working
bios.

A more expensive alternative would be to have a true ROM backing the
eeprom, and a motherboard switch/strap which enabled the rom version,
preferably also allowing reprogramming the eeprom part.

The company I work for has 20K+ PC's worldwide (100+ countries), so
naturally we couldn't keep the anti-virus sw up to date on all of them,
but CIH was limited to hitting 3 machines.

Of these three two had a sensible bios, and the third allowed filling
the eeprom with all FFs.

This PC would also have suffered a permanent crash if we had had a power
failure while loading a new (Y2K-compliant) bios update.

Terje

-- 
- <Terje.Mathisen@hda.hydro.com>
Using self-discipline, see http://www.eiffel.com/discipline
"almost all programming can be viewed as an exercise in caching"