Re: [net-next PATCH v6 0/3] net: reserve ports for applications using fixed port numbers

[Cong Wang <amwang@redhat.com>]

Eric W. Biederman wrote:
> 
> I would add the restriction that the values in the list of ranges
> always must be increasing, and in general restrict the set of accepted
> values as much as possible.  If we don't accept it now we don't have
> to worry about some userspace application relying on some unitended
> side effect a few years into the future.

I don't think this is good.

Suppose that when I just want to add one port into the list and keep the
original ones, I want to do this:

orig=$(cat ip_local_reserved_ports)
new_list="$orig, $new_one"
echo "$new_list" > ip_local_reserved_ports

If we add this restriction, the above could be failed if the new port
is lower than the original ones. This will be not convenient.

> 
> 
> I think it is a serious bug that you clear the destination bitmap
> in the middle of parsing it.  That will either open or close all
> ports in the middle of parsing, and I can't see how that would
> ever be a good thing.
> 

Agreed.

By the way, Octavian, any new updates?