net: fix the counter ICMP_MIB_INERRORS/ICMP6_MIB_INERRORS

When dealing with ICMPv[46] Error Message, function icmp_socket_deliver()
and icmpv6_notify() do some valid checks on packet's length, but then some
protocols check packet's length redaudantly. So remove those duplicated
statements, and increase counter ICMP_MIB_INERRORS/ICMP6_MIB_INERRORS in
function icmp_socket_deliver() and icmpv6_notify() respectively.

In addition, add missed counter in udp6/udplite6 when socket is NULL.

Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 1 deletions

diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 42b7bcf8045b..092400ef88d0 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -663,8 +663,10 @@ static void icmp_socket_deliver(struct sk_buff *skb, u32 info)
         /* Checkin full IP header plus 8 bytes of protocol to
          * avoid additional coding at protocol handlers.
          */
-        if (!pskb_may_pull(skb, iph->ihl * 4 + 8))
+        if (!pskb_may_pull(skb, iph->ihl * 4 + 8)) {
+                ICMP_INC_STATS_BH(dev_net(skb->dev), ICMP_MIB_INERRORS);
                 return;
+        }
 
         raw_icmp_error(skb, protocol, info);