vnet_buffer (b0)->l4_hdr_offset = hdr->csum_start;
b0->flags |= (VNET_BUFFER_F_L2_HDR_OFFSET_VALID |
VNET_BUFFER_F_L3_HDR_OFFSET_VALID |
vnet_buffer (b0)->l4_hdr_offset = hdr->csum_start;
b0->flags |= (VNET_BUFFER_F_L2_HDR_OFFSET_VALID |
VNET_BUFFER_F_L3_HDR_OFFSET_VALID |