From mboxrd@z Thu Jan 1 00:00:00 1970 From: Randy Dunlap Subject: Re: network interfaces called "all", "default" or "config" Date: Wed, 23 Jul 2014 07:56:38 -0700 Message-ID: <53CFCD26.1020409@infradead.org> References: <20140723113314.GA7798@chaz.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: Stephane Chazelas , linux-kernel@vger.kernel.org, "netdev@vger.kernel.org" Return-path: In-Reply-To: <20140723113314.GA7798@chaz.gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org [adding netdev] On 07/23/2014 04:33 AM, Stephane Chazelas wrote: > Hiya, > > you may want to forbid the creation of interfaces whose name is > one of the special files in /proc/net and /proc/sys. > > I can see some characters (like space, tab, newline, slash, > dot...) are alread forbidden in interface names (EINVAL), but > one can do for instance: > > sudo ip link add link eth0 all type vlan id 2 > sudo ip link add link eth0 default type vlan id 3 > sudo ip link add link eth0 config type vlan id 4 > > Interestingly, after you add a "all" or "default", the > corresponding /proc/sys/net/ipv[46]/conf/(all|default) become > empty, and remain so even after you've removed the interface. > > Adding an interface called "config" masks /proc/net/vlan/config > > (tested with 3.14-1-amd64 on debian) > -- ~Randy