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Date: Tue, 13 Sep 2011 16:14:14 +0200
From: Pavel Machek <pavel@ucw.cz>
To: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Nathan Lynch <ntl@pobox.com>, Oren Laadan <orenl@cs.columbia.edu>,
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        James Bottomley <jbottomley@parallels.com>
Subject: Re: [RFC] fs, proc: Introduce the /proc/<pid>/map_files/ directory
 v2
Message-ID: <20110913141412.GB7604@ucw.cz>
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Hi!

> This one behaves similarly to the /proc/<pid>/fd/ one - it contains symlinks
> one for each mapping with file, the name of a symlink is vma->vm_start, the
> target is the file. Opening a symlink results in a file that point exactly
> to the same inode as them vma's one.

Is it good idea security-wise? It looks like symlink but does not
behave like one. (And yes, I know we already have similar problems in
/proc..)

ptrace-may-trace is not good enough protection; I can do  this on my
own thread to get around read-only protection on fd. (File can be
protected from me by directory permissions.)


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