From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754385Ab1AFAaR (ORCPT ); Wed, 5 Jan 2011 19:30:17 -0500 Received: from kroah.org ([198.145.64.141]:35812 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754354Ab1AFAaM (ORCPT ); Wed, 5 Jan 2011 19:30:12 -0500 X-Mailbox-Line: From gregkh@clark.site Wed Jan 5 16:23:04 2011 Message-Id: <20110106002304.076081785@clark.site> User-Agent: quilt/0.48-11.2 Date: Wed, 05 Jan 2011 16:22:57 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Vasiliy Kulikov , "David S. Miller" Subject: [078/152] net: packet: fix information leak to userland In-Reply-To: <20110106002500.GA3172@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.36-stable review patch. If anyone has any objections, please let us know. ------------------ From: Vasiliy Kulikov [ Upstream commit 67286640f638f5ad41a946b9a3dc75327950248f ] packet_getname_spkt() doesn't initialize all members of sa_data field of sockaddr struct if strlen(dev->name) < 13. This structure is then copied to userland. It leads to leaking of contents of kernel stack memory. We have to fully fill sa_data with strncpy() instead of strlcpy(). The same with packet_getname(): it doesn't initialize sll_pkttype field of sockaddr_ll. Set it to zero. Signed-off-by: Vasiliy Kulikov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/packet/af_packet.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1721,7 +1721,7 @@ static int packet_getname_spkt(struct so rcu_read_lock(); dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex); if (dev) - strlcpy(uaddr->sa_data, dev->name, 15); + strncpy(uaddr->sa_data, dev->name, 14); else memset(uaddr->sa_data, 0, 14); rcu_read_unlock(); @@ -1744,6 +1744,7 @@ static int packet_getname(struct socket sll->sll_family = AF_PACKET; sll->sll_ifindex = po->ifindex; sll->sll_protocol = po->num; + sll->sll_pkttype = 0; rcu_read_lock(); dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex); if (dev) {