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From: Junio C Hamano <gitster@pobox.com>
To: Jonathan Tan <jonathantanmy@google.com>
Cc: git@vger.kernel.org, markbt@efaref.net, git@jeffhostetler.com,
	kevin.david@microsoft.com
Subject: Re: Proposal for missing blob support in Git repos
Date: Mon, 01 May 2017 16:29:20 -0700	[thread overview]
Message-ID: <xmqq1ss8gnqn.fsf@gitster.mtv.corp.google.com> (raw)
In-Reply-To: <193d1d84-2386-c4c8-81ef-0042f0d8bb02@google.com> (Jonathan Tan's message of "Mon, 1 May 2017 12:12:27 -0700")

Jonathan Tan <jonathantanmy@google.com> writes:

> Thanks for your comments. If you're referring to the codepath
> involving write_sha1_file() (for example, builtin/hash-object ->
> index_fd or builtin/unpack-objects), that is fine because
> write_sha1_file() invokes freshen_packed_object() and
> freshen_loose_object() directly to check if the object already exists
> (and thus does not invoke the new mechanism in this patch).

Is that a good thing, though?  It means that you an attacker can
feed one version to the remote object store your "grab blob" hook
gets the blobs from, and have you add a colliding object locally,
and the usual "are we recording the same object as existing one?"
check is bypassed.


  reply	other threads:[~2017-05-01 23:29 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-04-26 22:13 Proposal for missing blob support in Git repos Jonathan Tan
2017-05-01  3:57 ` Junio C Hamano
2017-05-01 19:12   ` Jonathan Tan
2017-05-01 23:29     ` Junio C Hamano [this message]
2017-05-02  0:33       ` Jonathan Tan
2017-05-02  0:38         ` Brandon Williams
2017-05-02  1:41         ` Junio C Hamano
2017-05-02 17:21           ` Jonathan Tan
2017-05-02 18:32             ` Ævar Arnfjörð Bjarmason
2017-05-02 21:45               ` Jonathan Tan
2017-05-04  4:29                 ` Junio C Hamano
2017-05-04 17:09                   ` Jonathan Tan

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