net: Add MIB counters for checksum errors

Add MIB counters for checksum errors in IP layer,
and TCP/UDP/ICMP layers, to help diagnose problems.

$ nstat -a | grep  Csum
IcmpInCsumErrors                72                 0.0
TcpInCsumErrors                 382                0.0
UdpInCsumErrors                 463221             0.0
Icmp6InCsumErrors               75                 0.0
Udp6InCsumErrors                173442             0.0
IpExtInCsumErrors               10884              0.0

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 15 insertions, 6 deletions

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index da6019b63730..d4defdd44937 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -483,12 +483,17 @@ out:
 csum_copy_err:
         slow = lock_sock_fast(sk);
         if (!skb_kill_datagram(sk, skb, flags)) {
-                if (is_udp4)
+                if (is_udp4) {
+                        UDP_INC_STATS_USER(sock_net(sk),
+                                        UDP_MIB_CSUMERRORS, is_udplite);
                         UDP_INC_STATS_USER(sock_net(sk),
                                         UDP_MIB_INERRORS, is_udplite);
-                else
+                } else {
+                        UDP6_INC_STATS_USER(sock_net(sk),
+                                        UDP_MIB_CSUMERRORS, is_udplite);
                         UDP6_INC_STATS_USER(sock_net(sk),
                                         UDP_MIB_INERRORS, is_udplite);
+                }
         }
         unlock_sock_fast(sk, slow);
 
@@ -637,7 +642,7 @@ int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 
         if (rcu_access_pointer(sk->sk_filter)) {
                 if (udp_lib_checksum_complete(skb))
-                        goto drop;
+                        goto csum_error;
         }
 
         if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf))
@@ -656,6 +661,8 @@ int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
         bh_unlock_sock(sk);
 
         return rc;
+csum_error:
+        UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
 drop:
         UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
         atomic_inc(&sk->sk_drops);
@@ -817,7 +824,7 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
         }
 
         if (udp6_csum_init(skb, uh, proto))
-                goto discard;
+                goto csum_error;
 
         /*
          *      Multicast receive code
@@ -850,7 +857,7 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
                 goto discard;
 
         if (udp_lib_checksum_complete(skb))
-                goto discard;
+                goto csum_error;
 
         UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
@@ -867,7 +874,9 @@ short_packet:
                        skb->len,
                        daddr,
                        ntohs(uh->dest));
-
+        goto discard;
+csum_error:
+        UDP6_INC_STATS_BH(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
 discard:
         UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
         kfree_skb(skb);