From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758205Ab1DMPzt (ORCPT ); Wed, 13 Apr 2011 11:55:49 -0400 Received: from kroah.org ([198.145.64.141]:54424 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758137Ab1DMPzk (ORCPT ); Wed, 13 Apr 2011 11:55:40 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Apr 13 08:51:47 2011 Message-Id: <20110413155147.447736395@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Wed, 13 Apr 2011 08:51:06 -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 , Patrick McHardy Subject: [42/74] netfilter: arp_tables: fix infoleak to userspace 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 42eab94fff18cb1091d3501cd284d6bd6cc9c143 upstream. Structures ipt_replace, compat_ipt_replace, and xt_get_revision are copied from userspace. Fields of these structs that are zero-terminated strings are not checked. When they are used as argument to a format string containing "%s" in request_module(), some sensitive information is leaked to userspace via argument of spawned modprobe process. The first bug was introduced before the git epoch; the second is introduced by 6b7d31fc (v2.6.15-rc1); the third is introduced by 6b7d31fc (v2.6.15-rc1). To trigger the bug one should have CAP_NET_ADMIN. Signed-off-by: Vasiliy Kulikov Signed-off-by: Patrick McHardy Signed-off-by: Greg Kroah-Hartman --- net/ipv4/netfilter/arp_tables.c | 3 +++ 1 file changed, 3 insertions(+) --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -1086,6 +1086,7 @@ static int do_replace(struct net *net, v /* overflow check */ if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) return -ENOMEM; + tmp.name[sizeof(tmp.name)-1] = 0; newinfo = xt_alloc_table_info(tmp.size); if (!newinfo) @@ -1508,6 +1509,7 @@ static int compat_do_replace(struct net return -ENOMEM; if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) return -ENOMEM; + tmp.name[sizeof(tmp.name)-1] = 0; newinfo = xt_alloc_table_info(tmp.size); if (!newinfo) @@ -1763,6 +1765,7 @@ static int do_arpt_get_ctl(struct sock * ret = -EFAULT; break; } + rev.name[sizeof(rev.name)-1] = 0; try_then_request_module(xt_find_revision(NFPROTO_ARP, rev.name, rev.revision, 1, &ret),