From mboxrd@z Thu Jan  1 00:00:00 1970
From: "J. R. Okajima" <hooanon05@yahoo.co.jp>
Subject: Re: [Patch] Support overriding uid/gid in overlayfs
Date: Fri, 01 Feb 2013 13:45:34 +0900
Message-ID: <7500.1359693934@jrobl>
References: <1358254695.3380.16.camel@avalon> <CAJfpegt-3=dxqbSLykAF4M9OJn9TAnwEgGfr67wZaxYsuXKN1Q@mail.gmail.com> <1359388685.2499.16.camel@avalon> <CAJfpegtYpbBoErC22f1bJQrr_ZZQpredan89DckusBXDoCk6Xw@mail.gmail.com> <4997.1359651713@jrobl> <CAJfpegt4=BBXM4rGzT6WqSZUhn8vLjbFU0mPHUSkysL9_VQTWA@mail.gmail.com>
Cc: Alessandro Pignotti <alexpigna.dev@gmail.com>,
	Linux-Fsdevel <linux-fsdevel@vger.kernel.org>
To: Miklos Szeredi <miklos@szeredi.hu>
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Miklos Szeredi:
> They don't "solve" this, it's a fundamental property of the
> implementation.  Overlayfs and union-mounts behave as if copy-up was a
> "bind mount" over the file in question.  Yes, it's a namespace trick
> but it seems to work in most situations.

It must be a sad news for overlayfs users who have every met "non-most"
situations.


> The point was that uid/gid was to be overridden with *different*
> values for each overlayfs instance.  So implementing uid/gid
> overriding in the lower fs doesn't help.

For the scenario which Alessandro Pignotti posted,
- everything on the lower fs are owned by a single user, by the
  overriding feature.
- everything on the upper fs are owned by the user natively.
Isn't it enough?


J. R. Okajima