I don't think you have any option but to reinstall. After you have reinstalled, apply the patch before stopping the operating system in ANY way. Now, the wiki also states that you must have this patch on a CD or readable partition of some type (not SATA).
Well perhaps you can boot with -s option at startup. (single mode you will have a command shell as root)
Then after mount drive and then applied patch.
This may work butyou need some command prompt skill.