diff --git a/libc/kernel/uapi/linux/mptcp.h b/libc/kernel/uapi/linux/mptcp.h
index 6f5d272..3c9ba5e 100644
--- a/libc/kernel/uapi/linux/mptcp.h
+++ b/libc/kernel/uapi/linux/mptcp.h
@@ -52,6 +52,7 @@
   __u64 mptcpi_bytes_sent;
   __u64 mptcpi_bytes_received;
   __u64 mptcpi_bytes_acked;
+  __u8 mptcpi_subflows_total;
 };
 #define MPTCP_RST_EUNSPEC 0
 #define MPTCP_RST_EMPTCP 1