[TUHS] Bugs in V6 'dcheck'

Doug McIlroy doug at cs.dartmouth.edu
Sun Jun 1 09:24:57 AEST 2014

> Ken and Dennis and the other guys behind
> the earliest UNIX code were smart guys and good programmers,
> but they were far from perfect; and back in those days we
> were all a lot sloppier.

The observation that exploits may be able to parlay
mundane bugs into security holes was not a commonplace
back then--even in the Unix room. So input buffers were
often made "bigger than ever will be needed" and left
that way on the understanding that crashes are tolerable
on outlandish data. In an idle moment one day, Dennis fed
a huge line of input to most everything in /bin. To the
surprise of nobody, including Dennis, lots of programs
crashed. We WERE surprised a few years later, when a journal
published this fact as a research result. Does anybody 
remember who published that deep new insight and/or where?


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