nft_dup_ipv6
struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
.size = NFT_EXPR_SIZE(sizeof(struct nft_dup_ipv6)),