From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from msux-gh1-uea01.nsa.gov (msux-gh1-uea01.nsa.gov [63.239.67.1]) by tarius.tycho.ncsc.mil (8.13.1/8.13.1) with ESMTP id n62LRXND014312 for ; Thu, 2 Jul 2009 17:27:33 -0400 Received: from g5t0006.atlanta.hp.com (localhost [127.0.0.1]) by msux-gh1-uea01.nsa.gov (8.12.10/8.12.10) with ESMTP id n62LRGNx026638 for ; Thu, 2 Jul 2009 21:27:16 GMT Received: from g5t0029.atlanta.hp.com (g5t0029.atlanta.hp.com [16.228.8.141]) by g5t0006.atlanta.hp.com (Postfix) with ESMTP id 22801C645 for ; Thu, 2 Jul 2009 21:27:33 +0000 (UTC) From: Paul Moore Subject: [RFC PATCH v2] selinux: Fix a problem with socket labels and the TUN driver To: selinux@tycho.nsa.gov Date: Thu, 02 Jul 2009 17:27:24 -0400 Message-ID: <20090702212724.7080.70214.stgit@flek.lan> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: owner-selinux@tycho.nsa.gov List-Id: selinux@tycho.nsa.gov There is a problem where packets being sent by the TUN driver are not correctly handled by SELinux in the postrouting code. The issue is that the SELinux network access controls rely on a packet's associated sock, when present, for it's security label. The TUN driver does create a sock to send network traffic but it only calls into the LSM/SELinux code once via the security_sk_alloc() hook which never fully initializes the sock's label. This patch attempts to correct this problem by adding the normal LSM socket creation hooks to the TUN driver. NOTE: this is an RFC patch intended to demonstrate a possible solution completely different from the v1 patch, but it is still crude, untested and not fully hashed out just yet. Please take a look and see if this approach is even worth pursuing ... thanks. --- drivers/net/tun.c | 10 ++++++++++ 1 files changed, 10 insertions(+), 0 deletions(-) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 11a0ba4..7db4b13 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -946,6 +946,10 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) if (!capable(CAP_NET_ADMIN)) return -EPERM; + err = security_socket_create(AF_UNSPEC, SOCK_RAW, 0, 0); + if (err < 0) + return err; + /* Set dev type */ if (ifr->ifr_flags & IFF_TUN) { /* TUN device */ @@ -987,6 +991,12 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) tun->sk = sk; container_of(sk, struct tun_sock, sk)->tun = tun; + /* XXX - correct placement? */ + err = security_socket_post_create(tun->socket, + AF_UNSPEC, SOCK_RAW, 0, 0); + if (err < 0) + goto err_free_sk; + tun_net_init(dev); if (strchr(dev->name, '%')) { -- This message was distributed to subscribers of the selinux mailing list. If you no longer wish to subscribe, send mail to majordomo@tycho.nsa.gov with the words "unsubscribe selinux" without quotes as the message.