diff --git a/kernel/syscall.c b/kernel/syscall.c
index bff2f279..8cee87e6 100644
--- a/kernel/syscall.c
+++ b/kernel/syscall.c
@@ -76,7 +76,9 @@ static int sys_lseek(int fd, off_t pos, int origin)
 {
 	int ret = -EINVAL;
 
-	/* Beware: still not checking the filetype & size*/
+	if (BUILTIN_EXPECT(per_core(current_task)->fildes_table[fd].node->type != FS_FILE, 0))
+		return -EINVAL;
+	
 
 	switch(origin) 
 	{