Re: [PATCH 2/4] receive-pack: implement advertising and receiving push options

From: Jeff King <peff@peff.net>
Date: Jul 8, 2016, 21:46 UTC
Message-ID: <20160708214637.GB9820@sigill.intra.peff.net>
In-Reply-To: <CAGZ79ka8eHOx28Ja+S6DOGEOrV_ijUvi_NnjprhuzQ+3O9BAoQ@mail.gmail.com>

On Fri, Jul 08, 2016 at 11:57:20AM -0700, Stefan Beller wrote:

Show 11 quoted lines

> >> Sorry to butt into the conversation late, but: I am not yet convinced.
> >>
> >> Is the idea that if the push options were very large, this would save
> >> the client from the cost of sending them?
> >
> > Not really.  I have no strong opinion on the benefit of limiting
> > number/size.  Stefan limited the number/size at the receiving end
> > and made receiving end die with its message.
> 
> Jeff claimed we'd need some sort of DoS protection for this feature,
> so I considered just die-ing enough for an initial implementation.

I do not think we need to worry too much about niceties for these limits. The point is to protect servers from malicious nonsense, like somebody sending gigabytes of push options, or trying to overflow a buffer in a hook with a large value. If people are seeing these in routine use, then the limits are set too low, and this should happen roughly as often as a BUG assertion, and IMHO should be treated roughly the same: don't bother with translation, and don't worry about optimizing wasted bandwidth for this case. It won't happen enough to matter.

-Peff