diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index f001bad..d3ebc0e 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -574,6 +574,8 @@
 			   int fd_out, loff_t __user *off_out,
 			   size_t len, unsigned int flags);
 
+asmlinkage long sys_tee(int fdin, int fdout, size_t len, unsigned int flags);
+
 asmlinkage long sys_sync_file_range(int fd, loff_t offset, loff_t nbytes,
 					unsigned int flags);