Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932207Ab1DZVOP (ORCPT ); Tue, 26 Apr 2011 17:14:15 -0400 Received: from mga09.intel.com ([134.134.136.24]:58780 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758761Ab1DZVN7 (ORCPT ); Tue, 26 Apr 2011 17:13:59 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.64,270,1301900400"; d="scan'208";a="738831689" From: Andi Kleen References: <20110426212.641772347@firstfloor.org> In-Reply-To: <20110426212.641772347@firstfloor.org> To: segoon@openwall.com, kaber@trash.net, gregkh@suse.de, ak@linux.intel.com, linux-kernel@vger.kernel.org, stable@kernel.org, tim.bird@am.sony.com Subject: [PATCH] [31/106] netfilter: arp_tables: fix infoleak to userspace Message-Id: <20110426211310.5F4A33E1886@tassilo.jf.intel.com> Date: Tue, 26 Apr 2011 14:13:10 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2282 Lines: 61 2.6.35-longterm review patch. If anyone has any objections, please let me 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 Signed-off-by: Andi Kleen --- net/ipv4/netfilter/arp_tables.c | 3 +++ 1 file changed, 3 insertions(+) Index: linux-2.6.35.y/net/ipv4/netfilter/arp_tables.c =================================================================== --- linux-2.6.35.y.orig/net/ipv4/netfilter/arp_tables.c +++ linux-2.6.35.y/net/ipv4/netfilter/arp_tables.c @@ -1081,6 +1081,7 @@ static int do_replace(struct net *net, c /* 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) @@ -1502,6 +1503,7 @@ 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) @@ -1754,6 +1756,7 @@ 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), -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/