Re: [PATCH] signal: Extend exec_id to 64bits

[Linus Torvalds]

On Wed, Apr 1, 2020 at 4:51 PM Linus Torvalds
<torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> It's literally testing a sequence counter for equality. If you get
> tearing in the high bits on the write (or the read), you'd still need
> to have the low bits turn around 4G times to get a matching value.

Put another way: first you'd have to work however many weeks to do 4
billion execve() calls, and then you need to hit basically a
single-instruction race to take advantage of it.

Good luck with that. If you have that kind of God-like capability,
whoever you're attacking stands no chance in the first place.

                  Linus