John Richard Moser <nigelenki (at) comcast (dot) net [email concealed]> writes:

> PaX does pretty nice randomization. I think 15/16 for heap and stack
> and 24 for mmap(), though I could be overshooting the 24. I'm on amd64
> so I can't just run paxtest and see; though I could read the source code.

In some fairly reasonable circumstances, this may not be enough.
I wonder whether the security community is generally aware of a
paper I co-authored on defeating PaX and address space
randomization in general on 32-bit systems, titled "On the
Effectiveness of Address Space Randomization". It was presented
at CCS 2004 and available on my webpage, among other places:
http://www.stanford.edu/~blp/papers/asrandom.pdf
--
"To prepare for the writing of Software,
the writer must first become one with it,
sometimes two."
--W. C. Carlson

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