On Thu, Feb 23, 2017 at 8:13 PM, Morten Welinder [off-list ref] wrote:
The attack seems to generate two 64-bytes blocks, one quarter of which
is repeated data. (Table-1 in the paper.)
Assuming the result of that is evenly distributed and that bytes are
independent, we can estimate the chances that the result is NUL-free
as (255/256)^192 = 47% and the probability that the result is NUL and
newline free as (254/256)^192 = 22%. Clearly one should not rely of
NULs or newlines to save the day. On the other hand, the chances of
an ascii result is something like (95/256)^192 = 10^-83.
Good. So they can replace linux/Documentation/logo.gif, but not actual source
files, not even if they contain hex arrays with "device parameters" ;-)
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds