Motorola quite properly reported this problem to Xerox via an official `level 1 SIDR' (a bug report with an intended urgency of `needs to be fixed yesterday'). Because the text of each SIDR was entered into a database that could be viewed by quite a number of people, Motorola followed the approved procedure: they simply reported the problem as `Security SIDR', and attached all of the necessary documentation, ways-to-reproduce, etc.
The CP-V people at Xerox sat on their thumbs; they either didn't realize the severity of the problem, or didn't assign the necessary operating-system-staff resources to develop and distribute an official patch.
Months passed. The Motorola guys pestered their Xerox field-support rep, to no avail. Finally they decided to take direct action, to demonstrate to Xerox management just how easily the system could be cracked and just how thoroughly the security safeguards could be subverted.
They dug around in the operating-system listings and devised a thoroughly devilish set of patches. These patches were then incorporated into a pair of programs called `Robin Hood' and `Friar Tuck'. Robin Hood and Friar Tuck were designed to run as `ghost jobs' (daemons, in Unix terminology); they would use the existing loophole to subvert system security, install the necessary patches, and then keep an eye on one another's statuses in order to keep the system operator (in effect, the superuser) from aborting them.
One fine day, the system operator on the main CP-V software development system in El Segundo was surprised by a number of unusual phenomena. These included the following:
* Tape drives would rewind and dismount their tapes in the
middle of a job.
* Disk drives would seek back and forth so rapidly that they
would attempt to walk across the floor (see {walking
drives}).
* The card-punch output device would occasionally start up of
itself and punch a {lace card}. These would usually jam in
the punch.
* The console would print snide and insulting messages from
Robin Hood to Friar Tuck, or vice versa.
* The Xerox card reader had two output stackers; it could be
instructed to stack into A, stack into B, or stack into A
(unless a card was unreadable, in which case the bad card
was placed into stacker B). One of the patches installed by
the ghosts added some code to the card-reader
driver… after reading a card, it would flip over to the
opposite stacker. As a result, card decks would divide
themselves in half when they were read, leaving the operator
to recollate them manually.
Naturally, the operator called in the operating-system developers. They found the bandit ghost jobs running, and {gun}ned them… and were once again surprised. When Robin Hood was gunned, the following sequence of events took place:
!X id1
id1: Friar Tuck… I am under attack! Pray save me! id1: Off (aborted)
id2: Fear not, friend Robin! I shall rout the Sheriff of Nottingham's men!