NX bit emulation

Question

Can someone explain to me how the NX bit can be emulated on platforms like 32-bit x86 where the hardware doesn't provide it? I would be grateful for an explanation of the basics of how it is emulated, because I simply cannot imagine how this can be implemented. Thanks in advance.

Answer 1

You can read about Exec Shield , PaX PAGEEXEC and PaX SEGMEXEC .

Answer 2

I have never implemented NX emulation, but knowing something about x86, I think best of all about how it can work.

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