Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1754676AbdLFDPZ (ORCPT <rfc822;w@1wt.eu>);
        Tue, 5 Dec 2017 22:15:25 -0500
Received: from mail-qt0-f178.google.com ([209.85.216.178]:36779 "EHLO
        mail-qt0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1754345AbdLFDPV (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Tue, 5 Dec 2017 22:15:21 -0500
X-Google-Smtp-Source: AGs4zMaIvJZ6ouQp0NG5HOT0HDVPAX8hR0bx9BD6DFdQGdKChjU3ua0hEHu3kB0h8JTkIGmpx8M5Xg==
MIME-Version: 1.0
In-Reply-To: <ca498c45-a37a-ec2e-1faa-5a6ff81384f5@gmail.com>
References: <1512513982-20407-1-git-send-email-cernekee@chromium.org> <ca498c45-a37a-ec2e-1faa-5a6ff81384f5@gmail.com>
From: Kevin Cernekee <cernekee@chromium.org>
Date: Tue, 5 Dec 2017 19:14:59 -0800
X-Gmail-Original-Message-ID: <CAJzqFtZ+-aYuEcUTgH9hUDfZJQpUuaMKRFzV5pERH3_5GyHKFA@mail.gmail.com>
Message-ID: <CAJzqFtZ+-aYuEcUTgH9hUDfZJQpUuaMKRFzV5pERH3_5GyHKFA@mail.gmail.com>
Subject: Re: [PATCH] netlink: Add netns check on taps
To: David Ahern <dsahern@gmail.com>
Cc: davem@davemloft.net, "Berg, Johannes" <johannes.berg@intel.com>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 433
Lines: 10

On Tue, Dec 5, 2017 at 6:19 PM, David Ahern <dsahern@gmail.com> wrote:
>> +     if (!net_eq(dev_net(dev), sock_net(sk)) &&
>> +         !net_eq(dev_net(dev), &init_net)) {
>
> Why is init_net special? Seems like snooping should be limited to the
> namespace you are in.

Depends how important it is to preserve the current "typical use case"
behavior, where the root user in the init netns can see all netlink
traffic on the system.