From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932353Ab3HMQEa (ORCPT ); Tue, 13 Aug 2013 12:04:30 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:18357 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758685Ab3HMP6c (ORCPT ); Tue, 13 Aug 2013 11:58:32 -0400 X-Authority-Analysis: v=2.0 cv=KJ7Y/S5o c=1 sm=0 a=Sro2XwOs0tJUSHxCKfOySw==:17 a=Drc5e87SC40A:10 a=Ciwy3NGCPMMA:10 a=n02W3ty1l3cA:10 a=5SG0PmZfjMsA:10 a=bbbx4UPp9XUA:10 a=meVymXHHAAAA:8 a=KGjhK52YXX0A:10 a=9zDUfKRsAmgA:10 a=20KFwNOVAAAA:8 a=J1Y8HTJGAAAA:8 a=okgtKhY1cvBJsHPla7wA:9 a=jEp0ucaQiEUA:10 a=4N9Db7Z2_RYA:10 a=jeBq3FmKZ4MA:10 a=Sro2XwOs0tJUSHxCKfOySw==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 67.255.60.225 Message-Id: <20130813155828.008964167@goodmis.org> User-Agent: quilt/0.60-1 Date: Tue, 13 Aug 2013 11:57:22 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Daniel Borkmann , "David S. Miller" Subject: [28/88] packet: packet_getname_spkt: make sure string is always 0-terminated References: <20130813155654.069291373@goodmis.org> Content-Disposition: inline; filename=0028-packet-packet_getname_spkt-make-sure-string-is-alway.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.6.11.7-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: Daniel Borkmann [ Upstream commit 2dc85bf323515e59e15dfa858d1472bb25cad0fe ] uaddr->sa_data is exactly of size 14, which is hard-coded here and passed as a size argument to strncpy(). A device name can be of size IFNAMSIZ (== 16), meaning we might leave the destination string unterminated. Thus, use strlcpy() and also sizeof() while we're at it. We need to memset the data area beforehand, since strlcpy does not padd the remaining buffer with zeroes for user space, so that we do not possibly leak anything. Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller Signed-off-by: Steven Rostedt --- net/packet/af_packet.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 13dee6a..a10ee11 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -2848,12 +2848,11 @@ static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr, return -EOPNOTSUPP; uaddr->sa_family = AF_PACKET; + memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data)); rcu_read_lock(); dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex); if (dev) - strncpy(uaddr->sa_data, dev->name, 14); - else - memset(uaddr->sa_data, 0, 14); + strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data)); rcu_read_unlock(); *uaddr_len = sizeof(*uaddr); -- 1.7.10.4