net: Handle encapsulated offloads before fragmentation or handing to lower dev

This change allows the VXLAN to enable Tx checksum offloading even on
devices that do not support encapsulated checksum offloads. The
advantage to this is that it allows for the lower device to change due
to routing table changes without impacting features on the VXLAN itself.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 0 deletions

diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 6537a408a4f..3e98ed2bff5 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -595,6 +595,10 @@ slow_path_clean:
         }
 
 slow_path:
+        /* for offloaded checksums cleanup checksum before fragmentation */
+        if ((skb->ip_summed == CHECKSUM_PARTIAL) && skb_checksum_help(skb))
+                goto fail;
+
         left = skb->len - hlen;         /* Space per frame */
         ptr = hlen;             /* Where to start from */