[UDP]: Clean up UDP-Lite receive checksum

This patch eliminates some duplicate code for the verification of
receive checksums between UDP-Lite and UDP.  It does this by
introducing __skb_checksum_complete_head which is identical to
__skb_checksum_complete_head apart from the fact that it takes
a length parameter rather than computing the first skb->len bytes.

As a result UDP-Lite will be able to use hardware checksum offload
for packets which do not use partial coverage checksums.  It also
means that UDP-Lite loopback no longer does unnecessary checksum
verification.

If any NICs start support UDP-Lite this would also start working
automatically.

This patch removes the assumption that msg_flags has MSG_TRUNC clear
upon entry in recvmsg.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 1 deletions

diff --git a/net/ipv4/udplite.c b/net/ipv4/udplite.c
index b28fe1edf98b..f34fd686a8f1 100644
--- a/net/ipv4/udplite.c
+++ b/net/ipv4/udplite.c
@@ -31,7 +31,7 @@ static int udplite_v4_get_port(struct sock *sk, unsigned short snum)
 
 static int udplite_rcv(struct sk_buff *skb)
 {
-        return __udp4_lib_rcv(skb, udplite_hash, 1);
+        return __udp4_lib_rcv(skb, udplite_hash, IPPROTO_UDPLITE);
 }
 
 static void udplite_err(struct sk_buff *skb, u32 info)