From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932338Ab1DMP4F (ORCPT ); Wed, 13 Apr 2011 11:56:05 -0400 Received: from kroah.org ([198.145.64.141]:54589 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932224Ab1DMP4B (ORCPT ); Wed, 13 Apr 2011 11:56:01 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Apr 13 08:51:49 2011 Message-Id: <20110413155149.863699915@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Wed, 13 Apr 2011 08:51:28 -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: [64/74] net: packet: fix information leak to userland In-Reply-To: <20110413155406.GA22568@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-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 [jmm: Backported to 2.6.32] 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 @@ -1526,7 +1526,7 @@ static int packet_getname_spkt(struct so uaddr->sa_family = AF_PACKET; dev = dev_get_by_index(sock_net(sk), pkt_sk(sk)->ifindex); if (dev) { - strlcpy(uaddr->sa_data, dev->name, 15); + strncpy(uaddr->sa_data, dev->name, 14); dev_put(dev); } else memset(uaddr->sa_data, 0, 14); @@ -1549,6 +1549,7 @@ 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; dev = dev_get_by_index(sock_net(sk), po->ifindex); if (dev) { sll->sll_hatype = dev->type;