--- zzzz-none-000/linux-4.19.183/include/uapi/linux/netfilter/xt_tcpudp.h	2021-03-24 10:07:39.000000000 +0000
+++ bcm63-7530ax-756/linux-4.19.183/include/uapi/linux/netfilter/xt_tcpudp.h	2023-06-28 08:54:20.000000000 +0000
@@ -12,6 +12,9 @@
 	__u8 flg_mask;			/* TCP flags mask byte */
 	__u8 flg_cmp;			/* TCP flags compare byte */
 	__u8 invflags;			/* Inverse flags */
+#if defined(CONFIG_BCM_KF_NETFILTER)
+	__u8 pure_ack;			/* Pure ACK packet */
+#endif
 };
 
 /* Values for "inv" field in struct ipt_tcp. */