On Tue, May 23, 2023 at 11:08 PM Jakub Kicinski <kuba@xxxxxxxxxx> wrote:
>
> On Tue, 23 May 2023 11:44:01 +0100 Luca Boccassi wrote:
> > > I really would like to avoid that because it will just mean that someone
> > > else will abuse that function and then make an argument why we should
> > > export the other function.
> > >
> > > I think it would be ok if we required that unix support is built in
> > > because it's not unprecedented either and we're not breaking anything.
> > > Bpf has the same requirement:
> > >
> > > #if IS_BUILTIN(CONFIG_UNIX) && defined(CONFIG_BPF_SYSCALL)
> > > struct bpf_unix_iter_state {
> > > struct seq_net_private p;
> > > unsigned int cur_sk;
> > > unsigned int end_sk;
> > > unsigned int max_sk;
> > > struct sock **batch;
> > > bool st_bucket_done;
> > > };
> > >
> > > and
> > >
> > > #if IS_BUILTIN(CONFIG_UNIX) && defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
> > > DEFINE_BPF_ITER_FUNC(unix, struct bpf_iter_meta *meta,
> > > struct unix_sock *unix_sk, uid_t uid)
>
> Don't think we should bring BPF into arguments about uAPI consistency :S
>
> > Some data points: Debian, Ubuntu, Fedora, RHEL, CentOS, Archlinux all
> > ship with CONFIG_UNIX=y, so a missing SCM_PIDFD in unlikely to have a
> > widespread impact, and if it does, it might encourage someone to
> > review their kconfig.
>
> IDK how you can argue that everyone sets UNIX to =y so hiding SCM_PIDFD
> is fine and at the same time not be okay with making UNIX a bool :S
>
> > As mentioned on the v5 thread, we are waiting for this API to get the
> > userspace side sorted (systemd/dbus/dbus-broker/polkit), so I'd be
> > really grateful if we could start with the simplest and most
> > conservative approach (which seems to be the current one in v6 to me),
> > and then eventually later decide whether to export more functions, or
> > to deprecate CONFIG_UNIX=m, or something else entirely, as that
> > doesn't really affect the shape of the UAPI, just the details of its
> > availability. Thank you.
>
> Just throw in a patch to make UNIX a bool and stop arguing then.
Dear Jakub,
Thanks for your attention to these patch series!
I'm ready to prepare/send a patch to make CONFIG_UNIX bool.
I will send SO_PEERPIDFD as an independent patch too, because it
doesn't require this change with CONFIG_UNIX
and we can avoid waiting until CONFIG_UNIX change will be merged.
I've a feeling that the discussion around making CONFIG_UNIX to be a
boolean won't be easy and fast ;-)
Kind regards,
Alex
