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Subject: Re: [PATCH] private mounts
From: Ram <linuxram@us.ibm.com>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: lmb@suse.de, mj@ucw.cz, linux-fsdevel@vger.kernel.org,
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On Wed, 2005-04-27 at 10:47, Miklos Szeredi wrote:
> > I think you need to disallow overmounts on invisible mounts by any user
> > other than the owner. If not, some other user (including root) can
> > overmount on your mount and the user will end up with DoS.
> 
> I'm not following you here.  How would an overmount cause DoS?

eg:
 
user 1 does a invisible mount on /mnt/mnt1
root does a visible mount on /mnt/mnt1

user 1 will no longer be able to access his /mnt/mnt1

in fact even if root mounts something on /mnt, the problem still exists.

RP

> 
> Thanks,
> Miklos

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