Re: [RFC] bridge: STP timer management range checking

Alan Cox
2008-09-01T08:56:05Z

> > Seems bogus extra code to me - stops things working that should be
> > allowed too.
> >
> The timer configuration is propagated in network protocol, so
> misconfigured Linux box
> could survive but effect other devices on the network that are less
> robust. Maybe the

That would be irrelevant. CAP_NET_ADMIN lets you make that size mess
anyway.

> small values would cause some other bridge to crash, go infinite loop, ...
> More likely robust devices might ignore our packets (because values out
> of range), leading to
> routing loops and other disasters.

Spamming tree isn't secure, news at 11.

> The kernel does need to stop administrative settings from taking out a
> network.

If you have CAP_NET_ADMIN you can trivially take out the network unless
it is properly switched.

Now you might want your pretty little GUI and/or config tools to warn
people that their configuration is outside 802 specs but that is a
different matter altogether

Alan