From mboxrd@z Thu Jan 1 00:00:00 1970 From: Duan Jiong Subject: [PATCH v3] ipv6: Change skb->data before using icmpv6_notify() to propagate redirect Date: Fri, 14 Dec 2012 20:59:59 +0800 Message-ID: <50CB22CF.9010505@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=GB2312 Content-Transfer-Encoding: 7bit Cc: Steffen Klassert , netdev@vger.kernel.org To: davem@davemloft.net Return-path: Received: from mail-da0-f46.google.com ([209.85.210.46]:62666 "EHLO mail-da0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752147Ab2LNNAF (ORCPT ); Fri, 14 Dec 2012 08:00:05 -0500 Received: by mail-da0-f46.google.com with SMTP id p5so1475388dak.19 for ; Fri, 14 Dec 2012 05:00:04 -0800 (PST) Sender: netdev-owner@vger.kernel.org List-ID: In function ndisc_redirect_rcv(), the skb->data points to the transport header, but function icmpv6_notify() need the skb->data points to the inner IP packet. So before using icmpv6_notify() to propagate redirect, change skb->data to point the inner IP packet that triggered the sending of the Redirect, and introduce struct rd_msg to make it easy. Signed-off-by: Duan Jiong --- include/net/ndisc.h | 7 +++++++ net/ipv6/ndisc.c | 17 +++++++++++++++++ 2 files changed, 24 insertions(+), 0 deletions(-) diff --git a/include/net/ndisc.h b/include/net/ndisc.h index 980d263..6b305d7 100644 --- a/include/net/ndisc.h +++ b/include/net/ndisc.h @@ -78,6 +78,13 @@ struct ra_msg { __be32 retrans_timer; }; +struct rd_msg { + struct icmp6hdr icmph; + struct in6_addr target; + struct in6_addr dest; + __u8 opt[0]; +}; + struct nd_opt_hdr { __u8 nd_opt_type; __u8 nd_opt_len; diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index 2edce30..89dab79 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -1314,6 +1314,12 @@ out: static void ndisc_redirect_rcv(struct sk_buff *skb) { + u8 *hdr; + struct ndisc_options ndopts; + struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb); + u32 ndoptlen = skb->tail - (skb->transport_header + + offsetof(struct rd_msg, opt)); + #ifdef CONFIG_IPV6_NDISC_NODETYPE switch (skb->ndisc_nodetype) { case NDISC_NODETYPE_HOST: @@ -1330,6 +1336,17 @@ static void ndisc_redirect_rcv(struct sk_buff *skb) return; } + if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) + return; + + if (!ndopts.nd_opts_rh) + return; + + hdr = (u8 *)ndopts.nd_opts_rh; + hdr += 8; + if (!pskb_pull(skb, hdr - skb_transport_header(skb))) + return; + icmpv6_notify(skb, NDISC_REDIRECT, 0, 0); } -- 1.7.1