Re: [PATCH v3 1/2] clone3: add CLONE_CLEAR_SIGHAND

From: Oleg Nesterov
Date: Mon Oct 21 2019 - 10:46:56 EST


On 10/14, Christian Brauner wrote:
>
> The child helper process on Linux posix_spawn must ensure that no signal
> handlers are enabled, so the signal disposition must be either SIG_DFL
> or SIG_IGN. However, it requires a sigprocmask to obtain the current
> signal mask and at least _NSIG sigaction calls to reset the signal
> handlers for each posix_spawn call

Plus the caller has to block/unblock all signals around clone(VM|VFORK).

Can this justify the new CLONE_ flag? Honestly, I have no idea. But the
patch is simple and looks technically correct to me. FWIW,

Reviewed-by: Oleg Nesterov <oleg@xxxxxxxxxx>