On Wed, Aug 19, 2020 at 08:53:42PM +0200, Mickaël Salaün wrote: > On 12/08/2020 12:06, Mark Rutland wrote: > > Contemporary W^X means that a given virtual alias cannot be writeable > > and executeable simultaneously, permitting (a) and (b). If you read the > > references on the Wikipedia page for W^X you'll see the OpenBSD 3.3 > > release notes and related presentation make this clear, and further they > > expect (b) to occur with JITS flipping W/X with mprotect(). > > W^X (with "permanent" mprotect restrictions [1]) goes back to 2000 with > PaX [2] (which predates partial OpenBSD implementation from 2003). > > [1] https://pax.grsecurity.net/docs/mprotect.txt > [2] https://undeadly.org/cgi?action=article;sid=20030417082752 Thanks for the pointers! Mark.