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Date: Tue, 27 Feb 2024 22:42:15 -0300
From: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
To: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	Gwendal Grignou <gwendal@chromium.org>, dlunev@chromium.org
Subject: Re: [PATCH] fat: ignore .. subdir and always add a link to dirs
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On Fri, Feb 23, 2024 at 09:29:35PM +0900, OGAWA Hirofumi wrote:
> Thadeu Lima de Souza Cascardo <cascardo@igalia.com> writes:
> 
> > So far, I have only seen expected correct behavior here: mkdir/rmdir inside the
> > "bogus" directory works. rmdir of the "bogus" directory works.
> >
> > The only idiosyncrasies I can think of is that if neither "." or ".." are
> > present, the directory will have a link of 1, instead of 2. And when listing
> > the directory, those entries will not show up.
> >
> > Do you expect any of these to be corrected? It will require a more convoluted
> > change.
> >
> > Right now, I think accepting the idiosyncratic behavior for the bogus
> > filesystems is fine, as long as the correct filesystems continue to behave as
> > before. Which seems to be the case here as far as my testing has shown.
> 
> There are many corrupted images, and attacks. Allowing too wide is
> danger for fs.
> 
> BTW, this image works and pass fsck on windows? When I quickly tested
> ev3fs.zip (https://github.com/microsoft/pxt-ev3/issues/980) on windows
> on qemu, it didn't seem recognized as FAT. I can wrongly tested though.
> 
> Thanks.
> -- 
> OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>

The test image I managed to create mounts just fine on Windows. New
subdirectories can be created there just as well.

Regards.
Cascardo.