[PATCH 3/3] capabilities: add cap userns sysctl mask

[Jonathan Calmels]

On Mon, May 20, 2024 at 07:30:14AM GMT, Tycho Andersen wrote:
> there is an ongoing effort (started at [0]) to constify the first arg
> here, since you're not supposed to write to it. Your usage looks
> correct to me, so I think all it needs is a literal "const" here.

Will do, along with the suggestions from Jarkko

> > +	struct ctl_table t;
> > +	unsigned long mask_array[2];
> > +	kernel_cap_t new_mask, *mask;
> > +	int err;
> > +
> > +	if (write && (!capable(CAP_SETPCAP) ||
> > +		      !capable(CAP_SYS_ADMIN)))
> > +		return -EPERM;
> 
> ...why CAP_SYS_ADMIN? You mention it in the changelog, but don't
> explain why.

No reason really, I was hoping we could decide what we want here.
UMH uses CAP_SYS_MODULE, Serge mentioned adding a new cap maybe.