From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nicolas Pitre <nico@cam.org>
Subject: Re: Performance issue: initial git clone causes massive repack
Date: Wed, 15 Apr 2009 07:51:22 -0400 (EDT)
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Cc: Nguyen Thai Ngoc Duy <pclouds@gmail.com>,
	"Robin H. Johnson" <robbat2@gentoo.org>,
	Johannes Schindelin <Johannes.Schindelin@gmx.de>,
	Git Mailing List <git@vger.kernel.org>
To: Junio C Hamano <gitster@pobox.com>
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On Tue, 14 Apr 2009, Junio C Hamano wrote:

> Nguyen Thai Ngoc Duy <pclouds@gmail.com> writes:
> 
> > How can you do that? If I understand git protocol correctly, there is
> > no difference between a fetch request and a clone one.
> 
> At the protocol level, you can tell a clone request by noticing that the
> downloading side does not have any "have" lines, but it is a different
> matter what the software does out of the box.
> 
> You can patch upload-pack to reject such requests.  I am sure gentoo folks
> are capable of doing that ;-)
> 
> Also a rogue client can send a bogus "have" to fool that logic, and that
> is the primary reason why we do not have such a patch to upload-pack.  It
> is not worth it as a protection against determined people who want to DoS.

Implementing a minimum treshold with merge-base to ensure that the 
client has at least commit X should be easy to do.  Unfortunately we 
don't have any hook for such a purpose yet.


Nicolas