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/proc filesystem allows bypassing directory permissions on Linux Oct 23 2009 05:16PM
Pavel Machek (pavel ucw cz) (4 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 26 2009 04:01PM
Tony Finch (dot dotat at) (3 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 27 2009 01:06PM
Pavel Machek (pavel ucw cz)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 26 2009 10:48PM
Matthew Dempsky (matthew dempsky org) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 27 2009 11:29AM
Tony Finch (dot dotat at) (2 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 27 2009 08:39PM
psz maths usyd edu au (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 28 2009 10:31PM
Glynn Clements (glynn gclements plus com)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 27 2009 04:59PM
Matthew Dempsky (matthew dempsky org)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 25 2009 10:13AM
Pavel Kankovsky (peak argo troja mff cuni cz)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 24 2009 01:55AM
Daryl Tester (dt-bugtraq handcraftedcomputers com au)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 23 2009 07:57PM
Dan Yefimov (dan lightwave net ru) (2 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 24 2009 06:46AM
Derek Martin (code pizzashack org) (1 replies)
Re: /proc filesystem allows bypassing directory permissions onLinux Oct 26 2009 06:37PM
Ansgar Wiechers (bugtraq planetcobalt net) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 27 2009 08:34PM
Derek Martin (code pizzashack org) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 23 2009 09:08PM
Pavel Machek (pavel ucw cz) (2 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 23 2009 11:47PM
psz maths usyd edu au (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 24 2009 07:02PM
Pavel Machek (pavel ucw cz) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 25 2009 12:40AM
psz maths usyd edu au (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 26 2009 10:42AM
Dan Yefimov (dan lightwave net ru)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 23 2009 09:24PM
Dan Yefimov (dan lightwave net ru) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 23 2009 09:56PM
Pavel Machek (pavel ucw cz) (2 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 26 2009 06:14PM
Joel Maslak (jmaslak antelope net)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 23 2009 10:31PM
Dan Yefimov (dan lightwave net ru) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 26 2009 04:14PM
Stephen Harris (bugtraq spuddy org) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 27 2009 11:04AM
Vincent Zweije vincent+bugtraq (at) sense.xs4all (dot) nl [email concealed] (vincent+bugtraq sense xs4all nl) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 27 2009 05:09PM
Dan Yefimov (dan lightwave net ru) (3 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 28 2009 09:27PM
Pavel Machek (pavel ucw cz) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 29 2009 03:24PM
Dan Yefimov (dan lightwave net ru) (1 replies)
Re: /proc filesystem allows bypassing directory permissions onLinux Oct 29 2009 07:20PM
Pavel Machek (pavel ucw cz) (1 replies)
Re: /proc filesystem allows bypassing directory permissions onLinux Oct 29 2009 08:10PM
Jim Paris (jim jtan com) (2 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 30 2009 05:57PM
Marco Verschuur (marco osp nl)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 30 2009 05:22PM
Marco Verschuur (marco osp nl) (2 replies)
Re: /proc filesystem allows bypassing directory permissions onLinux Oct 30 2009 05:40PM
Jim Paris (jim jtan com) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Nov 02 2009 05:53PM
Martin Rex (Martin Rex sap com) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Nov 02 2009 07:53PM
Pavel Machek (pavel ucw cz) (1 replies)
On Mon 2009-11-02 18:53:19, Martin Rex wrote:
> Jim Paris wrote:
> >
> > > Therefor it's totally of no influence what you do with the original
> > > directory permission. File access has nothing to do with directory
> > > permissions...!
> >
> > Right. However the whole point of this discussion is that that is a
> > non-obvious point, there was no other way that the user could have
> > opened that file without the use of /proc.
>
> The actual fallacy of the "problem report" is the flawed assumption
> about what a link count of 1 tells you.
>
> The link count of a files tells you the number of hard links that
> are persisted within the same filesystem. It is _NOT_ a promise
> that there are no other means to access the inode of the file.

It used to be promise before /proc was mounted.

> /proc creates a virtual reference to an inode, and since it is
> virtual (and in a different filesystem) and not persisted in the
> original filesystem, you will not see it in the link count of
> the original filesystem.

Well, there _may_ be other filesystems with similar features, but they
are neither common nor mounted by default.

Normally, mounting filesystems does not change security properties of
rest of the system; and it should be possible to fix in this case.

Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

[ reply ]
Re: /proc filesystem allows bypassing directory permissions on Nov 02 2009 08:56PM
Gabor Gombas (gombasg sztaki hu) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Nov 02 2009 11:33PM
Martin Rex (Martin Rex sap com) (3 replies)
Re: /proc filesystem allows bypassing directory permissions on Nov 04 2009 08:29PM
Pavel Kankovsky (peak argo troja mff cuni cz)
Re: /proc filesystem allows bypassing directory permissions on Nov 03 2009 01:06PM
Dan Yefimov (dan lightwave net ru)
Re: /proc filesystem allows bypassing directory permissions on Nov 03 2009 09:32AM
Gabor Gombas (gombasg sztaki hu) (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Nov 03 2009 11:17PM
psz maths usyd edu au (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Nov 04 2009 08:06AM
Gabor Gombas (gombasg sztaki hu) (3 replies)
Re: /proc filesystem allows bypassing directory permissions on Nov 04 2009 10:15AM
psz maths usyd edu au (1 replies)
Re: /proc filesystem allows bypassing directory permissions on Nov 04 2009 11:40AM
Gabor Gombas (gombasg sztaki hu)
Re: /proc filesystem allows bypassing directory permissions on Nov 04 2009 08:32AM
Pavel Machek (pavel ucw cz)
Re: /proc filesystem allows bypassing directory permissions on Nov 04 2009 08:31AM
Pavel Machek (pavel ucw cz)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 30 2009 05:38PM
Pavel Machek (pavel ucw cz) (2 replies)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 30 2009 06:27PM
Marco Verschuur (marco osp nl)
Re: /proc filesystem allows bypassing directory permissions on Linux Oct 28 2009 08:28PM
Vincent Zweije (vzweije zweije nl)







 

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