v4.19.13 snapshot.
diff --git a/include/uapi/linux/socket.h b/include/uapi/linux/socket.h
new file mode 100644
index 0000000..8eb9602
--- /dev/null
+++ b/include/uapi/linux/socket.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _UAPI_LINUX_SOCKET_H
+#define _UAPI_LINUX_SOCKET_H
+
+/*
+ * Desired design of maximum size and alignment (see RFC2553)
+ */
+#define _K_SS_MAXSIZE 128 /* Implementation specific max size */
+#define _K_SS_ALIGNSIZE (__alignof__ (struct sockaddr *))
+ /* Implementation specific desired alignment */
+
+typedef unsigned short __kernel_sa_family_t;
+
+struct __kernel_sockaddr_storage {
+ __kernel_sa_family_t ss_family; /* address family */
+ /* Following field(s) are implementation specific */
+ char __data[_K_SS_MAXSIZE - sizeof(unsigned short)];
+ /* space to achieve desired size, */
+ /* _SS_MAXSIZE value minus size of ss_family */
+} __attribute__ ((aligned(_K_SS_ALIGNSIZE))); /* force desired alignment */
+
+#endif /* _UAPI_LINUX_SOCKET_H */