Re: RSBAC mprotect
Javier Juan Martínez Cabezón <[email protected]> Mon, 22 Aug 2016 21:59:31 +0200
| Newsgroups | gmane.linux.rsbac |
|---|---|
| Message-ID | <[email protected]> |
> > If READ implies EXEC on some system, we cannot catch all cases, > because READ and WRITE together must be allowed. In my > understanding, on X86 systems this should only happen under 64 Bit > kernel with some 32 Bit programs. However, memory code is > complicated and I may have missed something. Please correct me, if > you know more than I do. > > Amon. > It should happen in almost all ia32 systems. NX under PaX on ia32 only got activated when PAE was active and there exists nx bit, I think this was because how NX was introduced, as a PAE extension. So you could have nx bit in some pentiums but dont get used at all if PAE were disable :S., so keys are to have NX (AFAIK in all amd64 and in "some" 32 bit systems) and to have PAE enabled http://www.gossamer-threads.com/lists/gentoo/hardened/180132