Re: [PATCH 2/4] rpcbind: allow broadcast RPC to be disabled.

[Petr Vorel <pvorel@suse.cz>]

Hi Neil,

> From: NeilBrown <neilb@suse.com>

> Support for broadcast RPC involves binding a second privileged
> port.  It is possible that rpcbind might choose a port that some
> other service will need, and that can cause problems.

> Having this port open increases the attack surface of rpcbind.  RPC
> replies can be sent to it by any host, and they will only be rejected
> once they have been parsed enough to determine that the xid doesn't
> match.

> Boardcast is not widely used.  It is not used at all for NFS.  For NIS
> (previously yellow pages) it can be used to find a local NIS server,
> though this can also be statically configured.

> In cases where broadcast-RPC is not needed, it is best to disable the
> port.  This patch adds a new "-b" option to disable broadcast RPC.

If this feature is wanted, I would suggest "-B". "-b" is used in ping for
broadcast, therefore this option looks like *enabling* broadcast instead of
disabling.

Otherwise LGTM.

Reviewed-by: Petr Vorel <pvorel@suse.cz>

Kind regards,
Petr