From: Pavel Machek <pavel@ucw.cz>
To: Jeff Layton <jlayton@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] procfs: make /proc style symlinks behave like "normal" symlinks
Date: Thu, 19 Nov 2009 22:39:35 +0100 [thread overview]
Message-ID: <20091119213935.GA11212@elf.ucw.cz> (raw)
In-Reply-To: <20091119143555.7851953f@barsoom.rdu.redhat.com>
> > Adding all of the short comings to followlink that readlink has is a problem,
> > especially as followlink does much better now.
> >
> > At a practical level I think your changes are much easier to exploit than
> > Pavels contrived example.
> >
> > I really don't have any problems with your first patch to proc to add the
> > missing revalidate.
> >
>
> Thanks, that makes sense. The raciness was evident once you pointed it
> out, so I think you're correct that we can't take this approach.
>
> Adding the missing revalidations is fine, but I don't believe that
> helps to fix Pavel's issue. I'll go back and take a more careful look
> at the suggestion that Miklos made and see whether it makes sense to
> implement a new FS_* flag for this, and see what it'll take to fix
> Pavel's issue.
One posibility would be to make open(/proc/XX/fd/XX) behave like
dup(). That should solve the NFS problems, too, no?
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
next prev parent reply other threads:[~2009-11-19 21:39 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-11-19 13:44 [PATCH] procfs: make /proc style symlinks behave like "normal" symlinks Jeff Layton
2009-11-19 17:07 ` Eric W. Biederman
2009-11-19 18:28 ` Jeff Layton
2009-11-19 18:57 ` Eric W. Biederman
2009-11-19 19:35 ` Jeff Layton
2009-11-19 21:31 ` Eric W. Biederman
2009-11-19 21:39 ` Pavel Machek [this message]
2009-11-19 21:56 ` Eric W. Biederman
2009-11-19 22:30 ` Pavel Machek
2009-11-20 9:31 ` Miklos Szeredi
2009-11-20 9:51 ` Pavel Machek
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