Re: [PATCH v4 1/2] kernel: Implement selective syscall userspace redirection

[Matthew Wilcox]

On Thu, Jul 16, 2020 at 03:31:40PM -0400, Gabriel Krisman Bertazi wrote:
> selector is an optional pointer to a char-sized userspace memory region
> that has a key switch for the mechanism. This key switch is set to
> either PR_SYS_DISPATCH_ON, PR_SYS_DISPATCH_OFF to enable and disable the
> redirection without calling the kernel.
> 
> The feature is meant to be set per-thread and it is disabled on
> fork/clone/execv.

Disabled on exec.  Disabled in the child on clone/fork (and vfork, I
think).

That means we don't need to worry about it interacting badly with
a setuid program, right?