Re: Avoid speculative indirect calls in kernel

[Willy Tarreau]

On Mon, Jan 08, 2018 at 05:22:41PM +0100, Borislav Petkov wrote:
> On Sun, Jan 07, 2018 at 11:10:38PM +0100, Willy Tarreau wrote:
> >  I just want to be clear that the big drop some of us are facing is
> > not an option *at all* for certain processes in certain environments
> > and that we'll either continue to run with pti=off or with pti=on + a
> > finer grained setting ASAP.
> 
> And that's all I'm saying: do pti=off in that case. The finer-grained
> "solution" is just silly.

I disagree because I want that, as much as possible, occasional
unprivileged local users can't exploit it. pti=off gives them full
access. The finer-grained solution ensures that only a few processes
share the same risk as the kernel as they work together to deliver
the service. And that's what I've implemented in a patch series I
sent in another thread :-)

   https://www.mail-archive.com/linux-kernel@xxxxxxxxxxxxxxx/msg1580131.html

Cheers,
Willy