From patchwork Thu Mar 10 18:12:07 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vasiliy Kulikov X-Patchwork-Id: 86325 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 8DE741007D1 for ; Fri, 11 Mar 2011 05:13:08 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753505Ab1CJSMS (ORCPT ); Thu, 10 Mar 2011 13:12:18 -0500 Received: from mail-bw0-f46.google.com ([209.85.214.46]:48933 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751713Ab1CJSMQ (ORCPT ); Thu, 10 Mar 2011 13:12:16 -0500 Received: by bwz15 with SMTP id 15so2047423bwz.19 for ; Thu, 10 Mar 2011 10:12:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:sender:from:to:cc:subject:date:message-id :x-mailer; bh=sj7ZtPSW8oxv9UwJOZYWU+zcLNPq4KsEf6/IohiOcTs=; b=uAEswjATkjAvba0vjPtS6+xMKMhd/wTUCj2FAfCb9KDHPcWLWOj6GVare08FcS5onR cIqjRiQVDXXhuCzmzwHHOOyJYthDoF8kgVpeJRf5ud4OtyUNvpWVtl/HQNTFMVt1H3hS iyU0CJz0Jf57kKMRJMGQjiRHfz13Pr1BDtqxY= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:from:to:cc:subject:date:message-id:x-mailer; b=YgouEJ5xE2l/pDDWGzyVUwc3BNVCrzABfPwu+A0WYYokGPzmguLoHKNcuhCa95ZYfF GhAKeq+/N/hG4lSkD0TNThGbjrnOyxQqfmcd8Gq3rzsJOiTnq98PdsYiEfYXEHV+bBZL PK45NXtGaiBy5HigBiIMEC7DvAccuT6HP8ueU= Received: by 10.204.20.74 with SMTP id e10mr134933bkb.148.1299780735002; Thu, 10 Mar 2011 10:12:15 -0800 (PST) Received: from localhost (ppp85-140-6-168.pppoe.mtu-net.ru [85.140.6.168]) by mx.google.com with ESMTPS id b6sm2330662bkb.22.2011.03.10.10.12.12 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 10 Mar 2011 10:12:13 -0800 (PST) From: Vasiliy Kulikov To: linux-kernel@vger.kernel.org Cc: security@kernel.org, Patrick McHardy , "David S. Miller" , Alexey Kuznetsov , James Morris , Hideaki YOSHIFUJI , netfilter-devel@vger.kernel.org, netfilter@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org Subject: [PATCH] ipv4: netfilter: arp_tables: fix infoleak to userspace Date: Thu, 10 Mar 2011 21:12:07 +0300 Message-Id: <1299780728-32565-1-git-send-email-segoon@openwall.com> X-Mailer: git-send-email 1.7.0.4 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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 --- Compile tested. net/ipv4/netfilter/arp_tables.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index e95054c..4b5d457 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -1066,6 +1066,7 @@ static int do_replace(struct net *net, const void __user *user, /* 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) @@ -1488,6 +1489,7 @@ static int compat_do_replace(struct net *net, void __user *user, 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) @@ -1740,6 +1742,7 @@ static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len 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),