From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Duan Jiong , "David S. Miller" Subject: [ 086/123] ipv6: Change skb->data before using icmpv6_notify() to propagate redirect Date: Wed, 9 Jan 2013 12:35:25 -0800 Message-Id: <20130109201509.644094471@linuxfoundation.org> In-Reply-To: <20130109201458.392601412@linuxfoundation.org> References: <20130109201458.392601412@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Duan Jiong [ Upstream commit 093d04d42fa094f6740bb188f0ad0c215ff61e2c ] 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 Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/net/ndisc.h | 7 +++++++ net/ipv6/ndisc.c | 17 +++++++++++++++++ 2 files changed, 24 insertions(+) --- 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; --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -1333,6 +1333,12 @@ 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: @@ -1349,6 +1355,17 @@ static void ndisc_redirect_rcv(struct sk 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); }