Re: [RFC PATCH for 4.18 1/2] rseq: validate rseq_cs fields are < TASK_SIZE

From: Linus Torvalds
Date: Mon Jul 02 2018 - 15:31:54 EST

On Mon, Jul 2, 2018 at 12:02 PM Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote:
> Works for me. Linus, any objection?

I think the 4.19 stage may be overkill, but I don't hate it, so no
real objections.

If the main reason for this is that we silently clear the upper bits
when returning to compat mode, I actually think that a better fix
would be to just fix that. We shouldn't silently ignore bogus data in
the return path.

But I don't care enough, I think.