[PATCH net-next] icmp: pass RFC 8335 reply messages to ping_rcv

[Andreas Roeseler <andreas.a.roeseler@gmail.com>]

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>
---
 net/ipv4/icmp.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 76990e13a2f9..8bd988fbcb31 100644
--- a/net/ipv4/icmp.c
+++ b/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
 	 *
-- 
2.30.0