Update dd.md

Author: Managor

pages/linux/dd.md

@@ -22,7 +22,7 @@
 
 - Create a system backup, save it into an IMG file (can be restored later by swapping `if` and `of`), and show the progress:
 
-`dd if={{/dev/drive_device}} of={{path/to/file.img}} status=progress`
+`sudo dd if={{/dev/drive_device}} of={{path/to/file.img}} status=progress`
 
 - Check the progress of an ongoing `dd` operation (run this command from another shell):