Re: [RFC] selftests/x86: Add test_vsyscall

From: Borislav Petkov
Date: Fri Jan 05 2018 - 14:10:08 EST


On Fri, Jan 05, 2018 at 10:45:49AM -0800, Andy Lutomirski wrote:
> Not _PAGE_RW. Probably _PAGE_USER somewhere in the hierarchy.

Yeah, just realized that. But it must be somewhere in the PT hierarchy
because:

0xffffffffff600000-0xffffffffff601000 4K USR ro NX pte

So something up needs to take _PAGE_USER too.

But WTF does it say NX there for and still can execute the vsyscall
test? Oh boy, what a mess...

--
Regards/Gruss,
Boris.

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