On Thu, Mar 26, 2020 at 07:58:29AM +0100, Michal Hocko wrote:
> On Wed 25-03-20 17:20:40, Eric W. Biederman wrote:
> > Vlastimil Babka <vbabka@xxxxxxx> writes:
> [...]
> > > + if (strncmp(param, "sysctl.", sizeof("sysctl.") - 1))
> > > + return 0;
> >
> > Is there any way we can use a slash separated path. I know
> > in practice there are not any sysctl names that don't have
> > a '.' in them but why should we artifically limit ourselves?
>
> Because this is the normal userspace interface? Why should it be any
> different from calling sysctl?
Right. The common method from userspace is dot-separated (which I agree
is weird, but it's been like this for ages: see manpages sysctl(8) and
sysctl.conf(5) for the details and examples). While "/" is accepted by
sysctl, the files shipped in /etc/sysctl.d/ are all using "." separators.
--
Kees Cook
