From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933087Ab1DMQRA (ORCPT ); Wed, 13 Apr 2011 12:17:00 -0400 Received: from kroah.org ([198.145.64.141]:53051 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932938Ab1DMQNd (ORCPT ); Wed, 13 Apr 2011 12:13:33 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Apr 13 09:10:49 2011 Message-Id: <20110413161048.971488108@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Wed, 13 Apr 2011 09:10:24 -0700 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" , Moritz Muehlenhoff Subject: [61/71] net: packet: fix information leak to userland In-Reply-To: <20110413161106.GA20405@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.33-longterm review patch. If anyone has any objections, please let us know. ------------------ From: Vasiliy Kulikov commit 67286640f638f5ad41a946b9a3dc75327950248f upstream. 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 Cc: Moritz Muehlenhoff 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 @@ -1523,7 +1523,7 @@ 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(); @@ -1546,6 +1546,7 @@ 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) {