Re: [PATCH 2/3] fsck: actually detect bad file modes in trees

From: Jeff King <peff@peff.net>
Date: Aug 10, 2022, 21:46 UTC
Message-ID: <YvQnIuVzMrOaM589@coredump.intra.peff.net>
In-Reply-To: <xmqq4jyjkcij.fsf@gitster.g>

On Wed, Aug 10, 2022 at 02:35:32PM -0700, Junio C Hamano wrote:

Show 11 quoted lines

> Jeff King <peff@peff.net> writes:
> 
> > We use the normal tree_desc code to iterate over trees in fsck, meaning
> > we only see the canonicalized modes it returns. And hence we'd never see
> > anything unexpected, since it will coerce literally any garbage into one
> > of our normal and accepted modes.
> 
> Wow.  I did know canon_mode() deliberately discarding the extra
> permission bits on trees and blobs, but it was that bad to mark
> whatever it does not understand as a gitlink.  That is simply
> horrible.

Yeah, I noticed that, as well. It might actually be reasonable to put a die() at the end of that canon_mode() function. It's rather unfriendly, but then, treating nonsense as a gitlink is likely to just result in the caller ending up aborting anyway.

Outside the scope of my patch, though. :)

-Peff