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Date: Thu, 15 Jan 2015 00:16:13 +0300
From: Cyrill Gorcunov <gorcunov@gmail.com>
To: Calvin Owens <calvinowens@fb.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>,
        Andrew Morton <akpm@linux-foundation.org>,
        Alexey Dobriyan <adobriyan@gmail.com>, Oleg Nesterov <oleg@redhat.com>,
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        Al Viro <viro@zeniv.linux.org.uk>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Peter Feiner <pfeiner@google.com>,
        Grant Likely <grant.likely@secretlab.ca>,
        Siddhesh Poyarekar <siddhesh.poyarekar@gmail.com>,
        linux-kernel@vger.kernel.org, kernel-team@fb.com,
        Pavel Emelyanov <xemul@openvz.org>
Subject: Re: [RFC][PATCH] procfs: Add /proc/<pid>/mapped_files
Message-ID: <20150114211613.GH2253@moon>
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On Wed, Jan 14, 2015 at 12:46:53PM -0800, Calvin Owens wrote:
> > > 
> > > Restriction to CAP_SYSADMIN for follow_link is undertansble, but why do we
> > > restrict readdir and readlink?
> > 
> > We didn't think this functionality might be needed someone but us (criu camp),
> > so that the rule of thumb was CONFIG_CHECKPOINT_RESTORE + CAP_SYSADMIN, until
> > otherwise strictly needed. So I think now we can relax security rules a bit
> > and allow to readdir and such for owners.
> 
> Ah, I feel silly for missing that. I'll send a patch to move map_files
> out from behind CONFIG_CHECKPOINT_RESTORE and change the permissions.

Sure