[NET]: Treat CHECKSUM_PARTIAL as CHECKSUM_UNNECESSARY

When a transmitted packet is looped back directly, CHECKSUM_PARTIAL
maps to the semantics of CHECKSUM_UNNECESSARY.  Therefore we should
treat it as such in the stack.

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

3 files changed, 5 insertions, 6 deletions

diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 2b3be68b70a7..f65fcd7704ca 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -368,7 +368,7 @@ int rawv6_rcv(struct sock *sk, struct sk_buff *skb)
                                      skb->len, inet->num, skb->csum))
                         skb->ip_summed = CHECKSUM_UNNECESSARY;
         }
-        if (skb->ip_summed != CHECKSUM_UNNECESSARY)
+        if (!skb_csum_unnecessary(skb))
                 skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
                                                          &ipv6_hdr(skb)->daddr,
                                                          skb->len,
@@ -421,7 +421,7 @@ static int rawv6_recvmsg(struct kiocb *iocb, struct sock *sk,
                 msg->msg_flags |= MSG_TRUNC;
         }
 
-        if (skb->ip_summed==CHECKSUM_UNNECESSARY) {
+        if (skb_csum_unnecessary(skb)) {
                 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
         } else if (msg->msg_flags&MSG_TRUNC) {
                 if (__skb_checksum_complete(skb))
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 7e824b97126d..2b668a6ae698 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1707,8 +1707,7 @@ static int tcp_v6_rcv(struct sk_buff **pskb)
         if (!pskb_may_pull(skb, th->doff*4))
                 goto discard_it;
 
-        if ((skb->ip_summed != CHECKSUM_UNNECESSARY &&
-             tcp_v6_checksum_init(skb)))
+        if (!skb_csum_unnecessary(skb) && tcp_v6_checksum_init(skb))
                 goto bad_packet;
 
         th = tcp_hdr(skb);
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 1e3dfb20b1cf..b083c09e3d2d 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -153,7 +153,7 @@ try_again:
                         goto csum_copy_err;
         }
 
-        if (skb->ip_summed == CHECKSUM_UNNECESSARY)
+        if (skb_csum_unnecessary(skb))
                 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
                                               msg->msg_iov, copied       );
         else {
@@ -397,7 +397,7 @@ static inline int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh,
                              skb->len, proto, skb->csum))
                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 
-        if (skb->ip_summed != CHECKSUM_UNNECESSARY)
+        if (!skb_csum_unnecessary(skb))
                 skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
                                                          &ipv6_hdr(skb)->daddr,
                                                          skb->len, proto, 0));