net: Save software checksum complete
In skb_checksum complete, if we need to compute the checksum for the
packet (via skb_checksum) save the result as CHECKSUM_COMPLETE.
Subsequent checksum verification can use this.
Also, added csum_complete_sw flag to distinguish between software and
hardware generated checksum complete, we should always be able to trust
the software computation.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/datagram.c b/net/core/datagram.c
index a16ed7b..6b1c04c 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -739,11 +739,15 @@
__sum16 sum;
sum = csum_fold(skb_checksum(skb, 0, len, skb->csum));
- if (likely(!sum)) {
- if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE))
- netdev_rx_csum_fault(skb->dev);
- skb->ip_summed = CHECKSUM_UNNECESSARY;
- }
+ if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) && !sum &&
+ !skb->csum_complete_sw)
+ netdev_rx_csum_fault(skb->dev);
+
+ /* Save checksum complete for later use */
+ skb->csum = sum;
+ skb->ip_summed = CHECKSUM_COMPLETE;
+ skb->csum_complete_sw = 1;
+
return sum;
}
EXPORT_SYMBOL(__skb_checksum_complete_head);
diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c
index 24deb39..eb92deb 100644
--- a/net/ipv4/gre_offload.c
+++ b/net/ipv4/gre_offload.c
@@ -131,10 +131,12 @@
csum_partial(skb->data, skb_gro_offset(skb), 0));
sum = csum_fold(NAPI_GRO_CB(skb)->csum);
if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE)) {
- if (unlikely(!sum))
+ if (unlikely(!sum) && !skb->csum_complete_sw)
netdev_rx_csum_fault(skb->dev);
- } else
+ } else {
skb->ip_summed = CHECKSUM_COMPLETE;
+ skb->csum_complete_sw = 1;
+ }
return sum;
}
diff --git a/net/sunrpc/socklib.c b/net/sunrpc/socklib.c
index 0a648c5..2df87f7 100644
--- a/net/sunrpc/socklib.c
+++ b/net/sunrpc/socklib.c
@@ -173,7 +173,8 @@
return -1;
if (csum_fold(desc.csum))
return -1;
- if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE))
+ if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
+ !skb->csum_complete_sw)
netdev_rx_csum_fault(skb->dev);
return 0;
no_checksum: