diff --git a/src/vnet/udp/udp.c b/src/vnet/udp/udp.c
index daab453..8f26b57 100644
--- a/src/vnet/udp/udp.c
+++ b/src/vnet/udp/udp.c
@@ -241,15 +241,12 @@
 
   vlib_buffer_push_udp (b, uc->c_lcl_port, uc->c_rmt_port, 1);
   if (tc->is_ip4)
-    vlib_buffer_push_ip4 (vm, b, &uc->c_lcl_ip4, &uc->c_rmt_ip4,
-			  IP_PROTOCOL_UDP, 1);
+    vlib_buffer_push_ip4_custom (vm, b, &uc->c_lcl_ip4, &uc->c_rmt_ip4,
+				 IP_PROTOCOL_UDP, 1 /* csum offload */ ,
+				 0 /* is_df */ );
   else
-    {
-      ip6_header_t *ih;
-      ih = vlib_buffer_push_ip6 (vm, b, &uc->c_lcl_ip6, &uc->c_rmt_ip6,
-				 IP_PROTOCOL_UDP);
-      vnet_buffer (b)->l3_hdr_offset = (u8 *) ih - b->data;
-    }
+    vlib_buffer_push_ip6 (vm, b, &uc->c_lcl_ip6, &uc->c_rmt_ip6,
+			  IP_PROTOCOL_UDP);
   vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
   vnet_buffer (b)->sw_if_index[VLIB_TX] = uc->c_fib_index;
   b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
diff --git a/src/vnet/udp/udp.h b/src/vnet/udp/udp.h
index f7985c9..ddc9a0e 100644
--- a/src/vnet/udp/udp.h
+++ b/src/vnet/udp/udp.h
@@ -308,10 +308,9 @@
   uh->checksum = 0;
   uh->length = clib_host_to_net_u16 (udp_len);
   if (offload_csum)
-    {
-      b->flags |= VNET_BUFFER_F_OFFLOAD_UDP_CKSUM;
-      vnet_buffer (b)->l4_hdr_offset = (u8 *) uh - b->data;
-    }
+    b->flags |= VNET_BUFFER_F_OFFLOAD_UDP_CKSUM;
+  vnet_buffer (b)->l4_hdr_offset = (u8 *) uh - b->data;
+  b->flags |= VNET_BUFFER_F_L4_HDR_OFFSET_VALID;
   return uh;
 }