audit: log 32-bit socketcalls

32-bit socketcalls were not being logged by audit on x86_64 systems.
Log them.  This is basically a duplicate of the call from
net/socket.c:sys_socketcall(), but it addresses the impedance mismatch
between 32-bit userspace process and 64-bit kernel audit.

See: https://github.com/linux-audit/audit-kernel/issues/14

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Moore <paul@paul-moore.com>
diff --git a/include/linux/audit.h b/include/linux/audit.h
index 9d4443f..2be99b2 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -387,6 +387,20 @@
 		return __audit_socketcall(nargs, args);
 	return 0;
 }
+
+static inline int audit_socketcall_compat(int nargs, u32 *args)
+{
+	unsigned long a[AUDITSC_ARGS];
+	int i;
+
+	if (audit_dummy_context())
+		return 0;
+
+	for (i = 0; i < nargs; i++)
+		a[i] = (unsigned long)args[i];
+	return __audit_socketcall(nargs, a);
+}
+
 static inline int audit_sockaddr(int len, void *addr)
 {
 	if (unlikely(!audit_dummy_context()))
@@ -513,6 +527,12 @@
 {
 	return 0;
 }
+
+static inline int audit_socketcall_compat(int nargs, u32 *args)
+{
+	return 0;
+}
+
 static inline void audit_fd_pair(int fd1, int fd2)
 { }
 static inline int audit_sockaddr(int len, void *addr)