From 9b8c6d7bf2e08a7d3eb6660a2bfaf29b8b49c329 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 18 Jun 2016 21:52:05 -0700 Subject: [PATCH] gre: better support for ICMP messages for gre+ipv6 ipgre_err() can call ip6_err_gen_icmpv6_unreach() for proper support of ipv4+gre+icmp+ipv6+... frames, used for example by traceroute/mtr. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/ip_tunnels.h | 1 + net/ipv4/gre_demux.c | 1 + net/ipv4/ip_gre.c | 6 ++++++ 3 files changed, 8 insertions(+) diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h index 9222678426a1..a5e7035fb93f 100644 --- a/include/net/ip_tunnels.h +++ b/include/net/ip_tunnels.h @@ -157,6 +157,7 @@ struct tnl_ptk_info { __be16 proto; __be32 key; __be32 seq; + int hdr_len; }; #define PACKET_RCVD 0 diff --git a/net/ipv4/gre_demux.c b/net/ipv4/gre_demux.c index 4c39f4fd332a..c4c3e439f424 100644 --- a/net/ipv4/gre_demux.c +++ b/net/ipv4/gre_demux.c @@ -117,6 +117,7 @@ int gre_parse_header(struct sk_buff *skb, struct tnl_ptk_info *tpi, if ((*(u8 *)options & 0xF0) != 0x40) hdr_len += 4; } + tpi->hdr_len = hdr_len; return hdr_len; } EXPORT_SYMBOL(gre_parse_header); diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 0f8ca3fca00a..ab4cff8e563d 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -187,6 +187,12 @@ static void ipgre_err(struct sk_buff *skb, u32 info, if (!t) return; +#if IS_ENABLED(CONFIG_IPV6) + if (tpi->proto == htons(ETH_P_IPV6) && + !ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len, type)) + return; +#endif + if (t->parms.iph.daddr == 0 || ipv4_is_multicast(t->parms.iph.daddr)) return; -- 2.39.2