Arch Linux

mandalar

Member

Registered: 2011-10-14

Posts: 7

NX bit implementation in kernel

Hi eveyone,
This is not an arch-specific question, but I'd like to know more how to NX (No eXecute) bit is implemented in the linux kernel.
It is what prevents some memory pages to be executed. Hence the stack and .data section of an ELF binary should not be executable.

I've got some general questions : is it an option you have to set up when compiling a program ? Can it be forced somehow for all programs ? But basically I'd like to find an overview of the technique and its implementation.

I didn't find much documentation on it so any pointer would be great.
Thanks.

falconindy

Developer

From: New York, USA

Registered: 2009-10-22

Posts: 4,111

Website

Re: NX bit implementation in kernel

http://people.redhat.com/mingo/nx-patch … rc2-bk2-AE

Seems like a good place to start -- it's Andi Kleen's original patch from 2004 when it was first introduced.

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