From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759445Ab2GLWgr (ORCPT ); Thu, 12 Jul 2012 18:36:47 -0400 Received: from mail-yw0-f46.google.com ([209.85.213.46]:40725 "EHLO mail-yw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759429Ab2GLWgl (ORCPT ); Thu, 12 Jul 2012 18:36:41 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg KH , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Paul Moore , "David S. Miller" Subject: [ 020/187] cipso: handle CIPSO options correctly when NetLabel is disabled Date: Thu, 12 Jul 2012 15:32:56 -0700 Message-Id: <20120712191524.135540029@linuxfoundation.org> X-Mailer: git-send-email 1.7.10.1.362.g242cab3 In-Reply-To: <20120712191522.742634173@linuxfoundation.org> References: <20120712192421.GA28926@kroah.com> <20120712191522.742634173@linuxfoundation.org> User-Agent: quilt/0.60-20.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Greg KH 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paul Moore [ Upstream commit 20e2a86485967c385d7c7befc1646e4d1d39362e ] When NetLabel is not enabled, e.g. CONFIG_NETLABEL=n, and the system receives a CIPSO tagged packet it is dropped (cipso_v4_validate() returns non-zero). In most cases this is the correct and desired behavior, however, in the case where we are simply forwarding the traffic, e.g. acting as a network bridge, this becomes a problem. This patch fixes the forwarding problem by providing the basic CIPSO validation code directly in ip_options_compile() without the need for the NetLabel or CIPSO code. The new validation code can not perform any of the CIPSO option label/value verification that cipso_v4_validate() does, but it can verify the basic CIPSO option format. The behavior when NetLabel is enabled is unchanged. Signed-off-by: Paul Moore Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/net/cipso_ipv4.h | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) --- a/include/net/cipso_ipv4.h +++ b/include/net/cipso_ipv4.h @@ -42,6 +42,7 @@ #include #include #include +#include /* known doi values */ #define CIPSO_V4_DOI_UNKNOWN 0x00000000 @@ -285,7 +286,33 @@ static inline int cipso_v4_skbuff_getatt static inline int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option) { - return -ENOSYS; + unsigned char *opt = *option; + unsigned char err_offset = 0; + u8 opt_len = opt[1]; + u8 opt_iter; + + if (opt_len < 8) { + err_offset = 1; + goto out; + } + + if (get_unaligned_be32(&opt[2]) == 0) { + err_offset = 2; + goto out; + } + + for (opt_iter = 6; opt_iter < opt_len;) { + if (opt[opt_iter + 1] > (opt_len - opt_iter)) { + err_offset = opt_iter + 1; + goto out; + } + opt_iter += opt[opt_iter + 1]; + } + +out: + *option = opt + err_offset; + return err_offset; + } #endif /* CONFIG_NETLABEL */