[NET]: IPV6 checksum offloading in network devices

The existing model for checksum offload does not correctly handle
devices that can offload IPV4 and IPV6 only. The NETIF_F_HW_CSUM flag
implies device can do any arbitrary protocol.

This patch:
 * adds NETIF_F_IPV6_CSUM for those devices
 * fixes bnx2 and tg3 devices that need it
 * add NETIF_F_IPV6_CSUM to ipv6 output (incl GSO)
 * fixes assumptions about NETIF_F_ALL_CSUM in nat
 * adjusts bridge union of checksumming computation

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 6 insertions, 3 deletions

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 041fba3fa0aa..06c08e5740fb 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1170,6 +1170,9 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int features)
         int ihl;
         int id;
 
+        if (!(features & NETIF_F_V4_CSUM))
+                features &= ~NETIF_F_SG;
+
         if (unlikely(skb_shinfo(skb)->gso_type &
                      ~(SKB_GSO_TCPV4 |
                        SKB_GSO_UDP |
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 34ea4547ebbe..a7dd343d3a03 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -837,7 +837,7 @@ int ip_append_data(struct sock *sk,
          */
         if (transhdrlen &&
             length + fragheaderlen <= mtu &&
-            rt->u.dst.dev->features & NETIF_F_ALL_CSUM &&
+            rt->u.dst.dev->features & NETIF_F_V4_CSUM &&
             !exthdrlen)
                 csummode = CHECKSUM_PARTIAL;
 
diff --git a/net/ipv4/netfilter/nf_nat_helper.c b/net/ipv4/netfilter/nf_nat_helper.c
index 15b6e5ce3a04..b1aa5983a95b 100644
--- a/net/ipv4/netfilter/nf_nat_helper.c
+++ b/net/ipv4/netfilter/nf_nat_helper.c
@@ -178,7 +178,7 @@ nf_nat_mangle_tcp_packet(struct sk_buff **pskb,
         datalen = (*pskb)->len - iph->ihl*4;
         if ((*pskb)->ip_summed != CHECKSUM_PARTIAL) {
                 if (!(rt->rt_flags & RTCF_LOCAL) &&
-                    (*pskb)->dev->features & NETIF_F_ALL_CSUM) {
+                    (*pskb)->dev->features & NETIF_F_V4_CSUM) {
                         (*pskb)->ip_summed = CHECKSUM_PARTIAL;
                         (*pskb)->csum_start = skb_headroom(*pskb) +
                                               skb_network_offset(*pskb) +
@@ -265,7 +265,7 @@ nf_nat_mangle_udp_packet(struct sk_buff **pskb,
 
         if ((*pskb)->ip_summed != CHECKSUM_PARTIAL) {
                 if (!(rt->rt_flags & RTCF_LOCAL) &&
-                    (*pskb)->dev->features & NETIF_F_ALL_CSUM) {
+                    (*pskb)->dev->features & NETIF_F_V4_CSUM) {
                         (*pskb)->ip_summed = CHECKSUM_PARTIAL;
                         (*pskb)->csum_start = skb_headroom(*pskb) +
                                               skb_network_offset(*pskb) +