fm10k: Check tunnel header length in encap offload

fm10k supports up to 184 bytes of inner+outer headers. Add an initial
check to fail encap offload if these are too large.

Signed-off-by: Joe Stringer <joestringer@nicira.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_main.c b/drivers/net/ethernet/intel/fm10k/fm10k_main.c
index c7a19a5e0ec9..84ab9eea2768 100644
--- a/drivers/net/ethernet/intel/fm10k/fm10k_main.c
+++ b/drivers/net/ethernet/intel/fm10k/fm10k_main.c
@@ -727,6 +727,12 @@ static __be16 fm10k_tx_encap_offload(struct sk_buff *skb)
         struct ethhdr *eth_hdr;
         u8 l4_hdr = 0;
 
+/* fm10k supports 184 octets of outer+inner headers. Minus 20 for inner L4. */
+#define FM10K_MAX_ENCAP_TRANSPORT_OFFSET        164
+        if (skb_inner_transport_header(skb) - skb_mac_header(skb) >
+            FM10K_MAX_ENCAP_TRANSPORT_OFFSET)
+                return 0;
+
         switch (vlan_get_protocol(skb)) {
         case htons(ETH_P_IP):
                 l4_hdr = ip_hdr(skb)->protocol;