icmp: ICMPV6: pass RFC 8335 reply messages to ping_rcv

The current icmp_rcv function drops all unknown ICMP types, including
ICMP_EXT_ECHOREPLY (type 43). In order to parse Extended Echo Reply messages, we have
to pass these packets to the ping_rcv function, which does not do any
other filtering and passes the packet to the designated socket.

Pass incoming RFC 8335 ICMP Extended Echo Reply packets to the ping_rcv
handler instead of discarding the packet.
Signed-off-by: Andreas Roeseler <andreas.a.roeseler@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/icmp.c

@@ -1196,6 +1196,11 @@ int icmp_rcv(struct sk_buff *skb)
 		goto success_check;
 	}
 
+	if (icmph->type == ICMP_EXT_ECHOREPLY) {
+		success = ping_rcv(skb);
+		goto success_check;
+	}
+
 	/*
 	 *	18 is the highest 'known' ICMP type. Anything else is a mystery
 	 *

net/ipv6/icmp.c

@@ -916,6 +916,10 @@ static int icmpv6_rcv(struct sk_buff *skb)
 		success = ping_rcv(skb);
 		break;
 
+	case ICMPV6_EXT_ECHO_REPLY:
+		success = ping_rcv(skb);
+		break;
+
 	case ICMPV6_PKT_TOOBIG:
 		/* BUGGG_FUTURE: if packet contains rthdr, we cannot update
 		   standard destination cache. Seems, only "advanced"