[IPV4] SNMP: Support InTruncatedPkts

An IP datagram which is being discarded because the datagram frame
didn't carry enough data should be counted as InTruncatedPkts.

Signed-off-by: Mitsuru Chinen <mitch@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 1 deletions

diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 63ab5230c611..c8c455dd9caf 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -416,7 +416,10 @@ int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
                 goto inhdr_error;
 
         len = ntohs(iph->tot_len);
-        if (skb->len < len || len < (iph->ihl*4))
+        if (skb->len < len) {
+                IP_INC_STATS_BH(IPSTATS_MIB_INTRUNCATEDPKTS);
+                goto drop;
+        } else if (len < (iph->ihl*4))
                 goto inhdr_error;
 
         /* Our transport medium may have padded the buffer out. Now we know it