[PATCH v3,net-next 2/2] ip6_gre: fix error path when ip6erspan_rcv failed

[Haishuang Yan]

Same as ipv4 code, when ip6erspan_rcv call return PACKET_REJECT, we
should call icmpv6_send to send icmp unreachable message in error path.

Fixes: 5a963eb61b7c ("ip6_gre: Add ERSPAN native tunnel support")
Acked-by: William Tu <u9012...@gmail.com>
Cc: William Tu <u9012...@gmail.com>
Signed-off-by: Haishuang Yan <yanhaishu...@cmss.chinamobile.com>

---
Change since v2:
  * Rebase on latest master branch.
  * Fix wrong commit information.
---
 net/ipv6/ip6_gre.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 45038a9..8451d00 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -604,12 +604,13 @@ static int gre_rcv(struct sk_buff *skb)
                     tpi.proto == htons(ETH_P_ERSPAN2))) {
                if (ip6erspan_rcv(skb, hdr_len, &tpi) == PACKET_RCVD)
                        return 0;
-               goto drop;
+               goto out;
        }
 
        if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
                return 0;
 
+out:
        icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
 drop:
        kfree_skb(skb);
-- 
1.8.3.1