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Date:   Thu, 16 Jul 2020 00:17:19 +0300
From:   Cyrill Gorcunov <gorcunov@gmail.com>
To:     Adrian Reber <areber@redhat.com>
Cc:     Christian Brauner <christian.brauner@ubuntu.com>,
        Eric Biederman <ebiederm@xmission.com>,
        Pavel Emelyanov <ovzxemul@gmail.com>,
        Oleg Nesterov <oleg@redhat.com>,
        Dmitry Safonov <0x7f454c46@gmail.com>,
        Andrei Vagin <avagin@gmail.com>,
        Nicolas Viennot <Nicolas.Viennot@twosigma.com>,
        =?utf-8?B?TWljaGHFgiBDxYJhcGnFhHNraQ==?= <mclapinski@google.com>,
        Kamil Yurtsever <kyurtsever@google.com>,
        Dirk Petersen <dipeit@gmail.com>,
        Christine Flood <chf@redhat.com>,
        Casey Schaufler <casey@schaufler-ca.com>,
        Mike Rapoport <rppt@linux.ibm.com>,
        Radostin Stoyanov <rstoyanov1@gmail.com>,
        Serge Hallyn <serge@hallyn.com>,
        Stephen Smalley <stephen.smalley.work@gmail.com>,
        Sargun Dhillon <sargun@sargun.me>,
        Arnd Bergmann <arnd@arndb.de>,
        linux-security-module@vger.kernel.org,
        linux-kernel@vger.kernel.org, selinux@vger.kernel.org,
        Eric Paris <eparis@parisplace.org>,
        Jann Horn <jannh@google.com>, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v5 4/6] proc: allow access in init userns for map_files
 with CAP_CHECKPOINT_RESTORE
Message-ID: <20200715211719.GH296695@grain>
References: <20200715144954.1387760-1-areber@redhat.com>
 <20200715144954.1387760-5-areber@redhat.com>
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On Wed, Jul 15, 2020 at 04:49:52PM +0200, Adrian Reber wrote:
> Opening files in /proc/pid/map_files when the current user is
> CAP_CHECKPOINT_RESTORE capable in the root namespace is useful for
> checkpointing and restoring to recover files that are unreachable via
> the file system such as deleted files, or memfd files.
> 
> Signed-off-by: Adrian Reber <areber@redhat.com>
> Signed-off-by: Nicolas Viennot <Nicolas.Viennot@twosigma.com>

I still have a plan to make this code been usable without
capabilities requirements but due to lack of spare time
for deep investigation this won't happen anytime soon.
Thus the patch looks OK to me, fwiw

Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com>