Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752195Ab3CREbE (ORCPT ); Mon, 18 Mar 2013 00:31:04 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33407 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750852Ab3CREaF (ORCPT ); Mon, 18 Mar 2013 00:30:05 -0400 Message-Id: <20130318042145.447908587@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Mon, 18 Mar 2013 04:21:56 +0000 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: akpm@linux-foundation.org, Kees Cook , Evgeniy Polyakov , Matt Helsley , "David S. Miller" Subject: [ 12/82] proc connector: reject unprivileged listener bumps In-Reply-To: <20130318042144.234468645@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:d98f:da4e:f620:7bea X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1658 Lines: 56 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kees Cook commit e70ab977991964a5a7ad1182799451d067e62669 upstream. While PROC_CN_MCAST_LISTEN/IGNORE is entirely advisory, it was possible for an unprivileged user to turn off notifications for all listeners by sending PROC_CN_MCAST_IGNORE. Instead, require the same privileges as required for a multicast bind. Signed-off-by: Kees Cook Cc: Evgeniy Polyakov Cc: Matt Helsley Acked-by: Evgeniy Polyakov Acked-by: Matt Helsley Signed-off-by: David S. Miller [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- drivers/connector/cn_proc.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/connector/cn_proc.c +++ b/drivers/connector/cn_proc.c @@ -303,6 +303,12 @@ static void cn_proc_mcast_ctl(struct cn_ if (msg->len != sizeof(*mc_op)) return; + /* Can only change if privileged. */ + if (!capable(CAP_NET_ADMIN)) { + err = EPERM; + goto out; + } + mc_op = (enum proc_cn_mcast_op*)msg->data; switch (*mc_op) { case PROC_CN_MCAST_LISTEN: @@ -315,6 +321,8 @@ static void cn_proc_mcast_ctl(struct cn_ err = EINVAL; break; } + +out: cn_proc_ack(err, msg->seq, msg->ack); } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/