From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <dj@redhat.com>
Received: from us-smtp-delivery-124.mimecast.com
 (us-smtp-delivery-124.mimecast.com [170.10.133.124])
 by sourceware.org (Postfix) with ESMTPS id 66D4C3858422
 for <libc-alpha@sourceware.org>; Thu, 18 Nov 2021 20:25:40 +0000 (GMT)
DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 66D4C3858422
Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com
 [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS
 (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id
 us-mta-70-5doyugQKNImlqTshioPZUg-1; Thu, 18 Nov 2021 15:25:38 -0500
X-MC-Unique: 5doyugQKNImlqTshioPZUg-1
Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com
 [10.5.11.12])
 (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))
 (No client certificate requested)
 by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D0652804141
 for <libc-alpha@sourceware.org>; Thu, 18 Nov 2021 20:25:37 +0000 (UTC)
Received: from greed.delorie.com (ovpn-112-12.phx2.redhat.com [10.3.112.12])
 by smtp.corp.redhat.com (Postfix) with ESMTPS id A416E60BF1;
 Thu, 18 Nov 2021 20:25:37 +0000 (UTC)
Received: from greed.delorie.com.redhat.com (localhost [127.0.0.1])
 by greed.delorie.com (8.15.2/8.15.2) with ESMTP id 1AIKPahi2960229;
 Thu, 18 Nov 2021 15:25:36 -0500
From: DJ Delorie <dj@redhat.com>
To: Florian Weimer <fweimer@redhat.com>
Cc: libc-alpha@sourceware.org
Subject: Re: [patch v3] Allow for unpriviledged nested containers
In-Reply-To: <87k0h5cj1c.fsf@oldenburg.str.redhat.com>
Date: Thu, 18 Nov 2021 15:25:36 -0500
Message-ID: <xnpmqx1a9r.fsf@greed.delorie.com>
MIME-Version: 1.0
X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12
X-Mimecast-Spam-Score: 0
X-Mimecast-Originator: redhat.com
Content-Type: text/plain
X-Spam-Status: No, score=-6.5 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH,
 DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW,
 RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NONE,
 TXREP autolearn=ham autolearn_force=no version=3.4.4
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on
 server2.sourceware.org
X-BeenThere: libc-alpha@sourceware.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Libc-alpha mailing list <libc-alpha.sourceware.org>
List-Unsubscribe: <https://sourceware.org/mailman/options/libc-alpha>,
 <mailto:libc-alpha-request@sourceware.org?subject=unsubscribe>
List-Archive: <https://sourceware.org/pipermail/libc-alpha/>
List-Post: <mailto:libc-alpha@sourceware.org>
List-Help: <mailto:libc-alpha-request@sourceware.org?subject=help>
List-Subscribe: <https://sourceware.org/mailman/listinfo/libc-alpha>,
 <mailto:libc-alpha-request@sourceware.org?subject=subscribe>
X-List-Received-Date: Thu, 18 Nov 2021 20:25:41 -0000

Florian Weimer <fweimer@redhat.com> writes:
> There is no new security issue because the patch could as well change
> support/test-container.c.

Right.  Our problem is a side-effect of the build container's security,
not extra security we're trying to impose to the test-container.

> The bind mount doesn't give you the /proc from the host, but from the
> container running the glibc build.  That still doesn't match the new PID
> namespace created by test-container, though.

Right.

>> Florian Weimer <fweimer@redhat.com> writes:
>>>> One process can have different PIDs depending on how you look at it.
>>>
>>> Then elf/tst-pldd should be fine with 4.
>>
>> Sure, but ...
>
> Sorry I meant 3b there.

Ah.

Hmmm... yes, I suppose if we don't create a new namespace, we'd lose the
ability to test pid 1 things, but /proc/<pid> would be consistent with
getpid().