On Thu, Oct 1, 2015 at 4:17 AM, Ingo Molnar <mi...@kernel.org> wrote: > > * Dave Hansen <d...@sr71.net> wrote: > >> > If yes then this could be a significant security feature / usecase for >> > pkeys:
Which CPUs (will) have pkeys? >> > executable sections of shared libraries and binaries could be mapped with >> > pkey >> > access disabled. If I read the Intel documentation correctly then that >> > should >> > be possible. >> >> Agreed. I've even heard from some researchers who are interested in this: >> >> https://www.infsec.cs.uni-saarland.de/wp-content/uploads/sites/2/2014/10/nuernberger2014ccs_disclosure.pdf > > So could we try to add an (opt-in) kernel option that enables this > transparently > and automatically for all PROT_EXEC && !PROT_WRITE mappings, without any > user-space changes and syscalls necessary? I would like this very much. :) > Beyond the security improvement, this would enable this hardware feature on > most > x86 Linux distros automatically, on supported hardware, which is good for > testing. > > Assuming it boots up fine on a typical distro, i.e. assuming that there are no > surprises where PROT_READ && PROT_EXEC sections are accessed as data. I can't wait to find out what implicitly expects PROT_READ from PROT_EXEC mappings. :) -Kees -- Kees Cook Chrome OS Security -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
