From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759236AbcEFXFK (ORCPT ); Fri, 6 May 2016 19:05:10 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:47063 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759207AbcEFXFI (ORCPT ); Fri, 6 May 2016 19:05:08 -0400 From: Tyler Hicks To: linux-security-module@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Serge Hallyn , "David S . Miller" Subject: [PATCH 2/2] net: Use ns_capable_noaudit() when determining net sysctl permissions Date: Fri, 6 May 2016 18:04:14 -0500 Message-Id: <1462575854-4301-3-git-send-email-tyhicks@canonical.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1462575854-4301-1-git-send-email-tyhicks@canonical.com> References: <1462575854-4301-1-git-send-email-tyhicks@canonical.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The capability check should not be audited since it is only being used to determine the inode permissions. A failed check does not indicate a violation of security policy but, when an LSM is enabled, a denial audit message was being generated. The denial audit message caused confusion for some application authors because root-running Go applications always triggered the denial. To prevent this confusion, the capability check in net_ctl_permissions() is switched to the noaudit variant. BugLink: https://launchpad.net/bugs/1465724 Signed-off-by: Tyler Hicks --- net/sysctl_net.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/sysctl_net.c b/net/sysctl_net.c index ed98c1f..46a71c7 100644 --- a/net/sysctl_net.c +++ b/net/sysctl_net.c @@ -46,7 +46,7 @@ static int net_ctl_permissions(struct ctl_table_header *head, kgid_t root_gid = make_kgid(net->user_ns, 0); /* Allow network administrator to have same access as root. */ - if (ns_capable(net->user_ns, CAP_NET_ADMIN) || + if (ns_capable_noaudit(net->user_ns, CAP_NET_ADMIN) || uid_eq(root_uid, current_euid())) { int mode = (table->mode >> 6) & 7; return (mode << 6) | (mode << 3) | mode; -- 2.7.4