4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Haishuang Yan <yanhaishuang@xxxxxxxxxxxxxxxxxxxx> [ Upstream commit dd8d5b8c5b22e31079b259b8bfb686f1fac1080a ] When erspan_rcv call return PACKET_REJECT, we shoudn't call ipgre_rcv to process packets again, instead send icmp unreachable message in error path. Fixes: 84e54fe0a5ea ("gre: introduce native tunnel support for ERSPAN") Acked-by: William Tu <u9012063@xxxxxxxxx> Cc: William Tu <u9012063@xxxxxxxxx> Signed-off-by: Haishuang Yan <yanhaishuang@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/ipv4/ip_gre.c | 2 ++ 1 file changed, 2 insertions(+) --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -408,11 +408,13 @@ static int gre_rcv(struct sk_buff *skb) if (unlikely(tpi.proto == htons(ETH_P_ERSPAN))) { if (erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD) return 0; + goto out; } if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD) return 0; +out: icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); drop: kfree_skb(skb);