Messages in this thread | | | From | Andy Lutomirski <> | Date | Mon, 14 Dec 2015 15:47:24 -0800 | Subject | Re: [PATCH 31/32] x86, pkeys: execute-only support |
| |
On Mon, Dec 14, 2015 at 3:44 PM, Dave Hansen <dave@sr71.net> wrote: > On 12/14/2015 03:39 PM, Andy Lutomirski wrote: >>> > Nope. My linker-fu is weak. >>> > >>> > Can we even depend on the linker by itself? Even if the sections were >>> > marked --x, we can't actually use them with those permissions unless we >>> > have protection keys. >>> > >>> > Do we need some special tag on the section to tell the linker to map it >>> > as --x under some conditions and r-x for others? >>> > >> Why? Wouldn't --x just end up acting like r-x if PKRU is absent? > > An app doing --x would expect it to be unreadable. I don't think we can > just silently turn it in to r-x.
I don't see why. After all, an app doing --x right now gets rx. An app doing r-- still gets r-x on some systems.
--Andy
-- Andy Lutomirski AMA Capital Management, LLC
| |