Re: [PATCH 1/2] fs/exec: allow to unshare a time namespace on vfork+exec

From: Kees Cook
Date: Wed Jun 15 2022 - 11:02:10 EST


On Sun, 12 Jun 2022 23:07:22 -0700, Andrei Vagin wrote:
> Right now, a new process can't be forked in another time namespace
> if it shares mm with its parent. It is prohibited, because each time
> namespace has its own vvar page that is mapped into a process address
> space.
>
> When a process calls exec, it gets a new mm and so it could be "legal"
> to switch time namespace in that case. This was not implemented and
> now if we want to do this, we need to add another clone flag to not
> break backward compatibility.
>
> [...]

Applied to for-next/execve, thanks!

[1/2] fs/exec: allow to unshare a time namespace on vfork+exec
https://git.kernel.org/kees/c/133e2d3e81de
[2/2] testing/timens: add a test for vfork+exit
https://git.kernel.org/kees/c/6342140db660

--
Kees Cook