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From: Duy Nguyen <pclouds@gmail.com>
To: Nicolas Pitre <nico@fluxnic.net>
Cc: Git Mailing List <git@vger.kernel.org>, Jeff King <peff@peff.net>
Subject: Re: pack corruption post-mortem
Date: Sat, 19 Oct 2013 17:32:43 +0700	[thread overview]
Message-ID: <CACsJy8ABdE8mZMVFZkqYMC4ZeN_baWw=XcYOZYBCZytWP97rRw@mail.gmail.com> (raw)
In-Reply-To: <20131016083400.GA31266@sigill.intra.peff.net>

On Wed, Oct 16, 2013 at 3:34 PM, Jeff King <peff@peff.net> wrote:
> I was recently presented with a repository with a corrupted packfile,
> and was asked if the data was recoverable. This post-mortem describes
> the steps I took to investigate and fix the problem. I thought others
> might find the process interesting, and it might help somebody in the
> same situation.
>
> I started with an fsck, which found a problem with exactly one object
> (I've used $pack and $obj below to keep the output readable, and also
> because I'll refer to them later):
>
>     $ git fsck
>     error: $pack SHA1 checksum mismatch
>     error: index CRC mismatch for object $obj from $pack at offset 51653873
>     error: inflate: data stream error (incorrect data check)
>     error: cannot unpack $obj from $pack at offset 51653873

I wonder if we should protect the sha-1 and pathname tables in packv4
with CRC too. A bit flipped in there could cause stream of corrupt
objects and make it hard to pinpoint the corrupt location..
-- 
Duy

  parent reply	other threads:[~2013-10-19 10:33 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-10-16  8:34 Jeff King
2013-10-16  8:59 ` Duy Nguyen
2013-10-16 15:41 ` Martin Fick
2013-10-17  0:35   ` Jeff King
2013-10-17 15:47     ` Junio C Hamano
2013-10-25  7:55       ` Jeff King
2013-10-17  1:06   ` Duy Nguyen
2013-10-19 10:32 ` Duy Nguyen [this message]
2013-10-19 14:41   ` Nicolas Pitre
2013-10-19 19:17     ` Shawn Pearce
2013-10-20 20:56       ` Nicolas Pitre
2013-10-20  4:44     ` Duy Nguyen
2013-10-20 21:08       ` Nicolas Pitre
2015-04-01 21:08 ` [PATCH] howto: document more tools for recovery corruption Jeff King
2015-04-01 22:21   ` Junio C Hamano
2015-04-02  0:49     ` Jeff King

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