From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm@xmission.com (Eric W. Biederman) Subject: Re: [PATCH] sysctl: allow override of /proc/sys/net with CAP_NET_ADMIN Date: Fri, 30 May 2008 18:59:26 -0700 Message-ID: References: <200805292349.m4TNneua029348@imap1.linux-foundation.org> <20080530161857.25e3fbc5@extreme> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: akpm@linuxfoundation.org, Chris Wright , stephen.hemminger@vyatta.com, adobriyan@gmail.com, morgan@kernel.org, xemul@openvz.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org To: Stephen Hemminger Return-path: Received: from out02.mta.xmission.com ([166.70.13.232]:49052 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750714AbYEaCBB (ORCPT ); Fri, 30 May 2008 22:01:01 -0400 In-Reply-To: <20080530161857.25e3fbc5@extreme> (Stephen Hemminger's message of "Fri, 30 May 2008 16:18:57 -0700") Sender: netdev-owner@vger.kernel.org List-ID: Stephen Hemminger writes: > Extend the permission check for networking sysctl's to allow > modification when current process has CAP_NET_ADMIN capability and > is not root. This version uses the until now unused permissions hook > to override the mode value for /proc/sys/net if accessed by a user > with capabilities. Looks reasonable but a little incomplete. Could you modify register_net_sysctl_table to set this attribute? Or alternatively all of the tables registered with register_net_sysctl. Otherwise I this will not affect all of the sysctls under /proc/sys/net. Which appears to be your intent. > Found while working with Quagga. It is impossible to turn forwarding > on/off through the command interface because Quagga uses secure coding > practice of dropping privledges during initialization and only raising > via capabilities when necessary. Since the dameon has reset real/effective > uid after initialization, all attempts to access /proc/sys/net variables > will fail. Eric