From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:37154 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933779AbeAXNuw (ORCPT ); Wed, 24 Jan 2018 08:50:52 -0500 Subject: Patch "netfilter: nfnetlink_cthelper: Add missing permission checks" has been added to the 4.9-stable tree To: cernekee@chromium.org, gregkh@linuxfoundation.org, mkubecek@suse.cz, pablo@netfilter.org Cc: , From: Date: Wed, 24 Jan 2018 14:50:12 +0100 Message-ID: <151680181213131@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled netfilter: nfnetlink_cthelper: Add missing permission checks to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: netfilter-nfnetlink_cthelper-add-missing-permission-checks.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 4b380c42f7d00a395feede754f0bc2292eebe6e5 Mon Sep 17 00:00:00 2001 From: Kevin Cernekee Date: Sun, 3 Dec 2017 12:12:45 -0800 Subject: netfilter: nfnetlink_cthelper: Add missing permission checks From: Kevin Cernekee commit 4b380c42f7d00a395feede754f0bc2292eebe6e5 upstream. The capability check in nfnetlink_rcv() verifies that the caller has CAP_NET_ADMIN in the namespace that "owns" the netlink socket. However, nfnl_cthelper_list is shared by all net namespaces on the system. An unprivileged user can create user and net namespaces in which he holds CAP_NET_ADMIN to bypass the netlink_net_capable() check: $ nfct helper list nfct v1.4.4: netlink error: Operation not permitted $ vpnns -- nfct helper list { .name = ftp, .queuenum = 0, .l3protonum = 2, .l4protonum = 6, .priv_data_len = 24, .status = enabled, }; Add capable() checks in nfnetlink_cthelper, as this is cleaner than trying to generalize the solution. Signed-off-by: Kevin Cernekee Signed-off-by: Pablo Neira Ayuso Acked-by: Michal Kubecek Signed-off-by: Greg Kroah-Hartman --- net/netfilter/nfnetlink_cthelper.c | 10 ++++++++++ 1 file changed, 10 insertions(+) --- a/net/netfilter/nfnetlink_cthelper.c +++ b/net/netfilter/nfnetlink_cthelper.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -392,6 +393,9 @@ static int nfnl_cthelper_new(struct net struct nfnl_cthelper *nlcth; int ret = 0; + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + if (!tb[NFCTH_NAME] || !tb[NFCTH_TUPLE]) return -EINVAL; @@ -595,6 +599,9 @@ static int nfnl_cthelper_get(struct net struct nfnl_cthelper *nlcth; bool tuple_set = false; + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + if (nlh->nlmsg_flags & NLM_F_DUMP) { struct netlink_dump_control c = { .dump = nfnl_cthelper_dump_table, @@ -661,6 +668,9 @@ static int nfnl_cthelper_del(struct net struct nfnl_cthelper *nlcth, *n; int j = 0, ret; + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + if (tb[NFCTH_NAME]) helper_name = nla_data(tb[NFCTH_NAME]); Patches currently in stable-queue which might be from cernekee@chromium.org are queue-4.9/netfilter-xt_osf-add-missing-permission-checks.patch queue-4.9/netfilter-nfnetlink_cthelper-add-missing-permission-checks.patch