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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Thu, 29 Sep 2022 14:13:57 -0700
Message-ID: <CAHk-=wgiBBXeY9ioZ8GtsxAcd42c265zwN7bYVY=cir01OimzA@mail.gmail.com>
Subject: Re: [PATCH 3/4] proc: Point /proc/net at /proc/thread-self/net
 instead of /proc/self/net
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     David Laight <David.Laight@aculab.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        "Serge E. Hallyn" <serge@hallyn.com>
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On Thu, Sep 29, 2022 at 12:34 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> Apparmor takes mount+dentry and turns that into pathname.  Then acts
> upon the resulting string.  *AFTER* the original had been resolved.

Ok. So it would have to act like a bind mount.

Which is probably not too bad.

In fact, maybe it would be ok for this to act like a hardlink and just
fill in the inode - not safe for a filesystem in general due to the
whole rename loop issue, but for /proc it might be fine?

                              Linus