From: Josef Wolf <jw@raven.inka.de>
To: git@vger.kernel.org
Subject: Re: What about SHA-1 collisions?
Date: Tue, 6 Nov 2012 23:09:38 +0100 [thread overview]
Message-ID: <20121106220938.GH28437@raven.wolf.lan> (raw)
In-Reply-To: <loom.20121106T223000-502@post.gmane.org>
On Tue, Nov 06, 2012 at 09:41:29PM +0000, John McKown wrote:
> Josef Wolf <jw <at> raven.inka.de> writes:
> > Just for curiosity: what would happen if such a collision would occur within
> > one repository?
> In a sense, this cannot happen.
In the scenario you described, contents of this version of file "b" are lost
and replaced by the contents of file "a". So file "b" is broken.
What happens when files "a" and "b" are added into different repositories?
File "a" is added to repos "A", and file "b" is added to repos "B". Now it
depends from which repository you fetch the collided blob first. If you fetch
it from "A", file "b" will be broken. If you fetch first from "B", your "a"
will be broken.
It becomes even more interesting, if some commit or tree object would have
the same SHA1 as some other object. I guess, in such a case the repository
would be completely hosed?
next prev parent reply other threads:[~2012-11-06 22:10 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-06 20:26 What about SHA-1 collisions? Josef Wolf
2012-11-06 21:41 ` John McKown
2012-11-06 22:09 ` Josef Wolf [this message]
2012-11-07 15:42 ` Shawn Pearce
2012-11-07 23:44 ` Andrew Ardill
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