Redboot FIS entry upgrade from Linux

[Jacob Avraham]

Hi,

Say I have a zImage or ramdisk image as a file listed in FIS,
which I use to  "fis load" from Redboot.
Now I want to upgrade an image from Linux, so in addition to
writing into the specific mtd partition I need to update the FIS
directory entry checksum value.

Are there any utils to facilitate that?
Or maybe such where not developed because it's not a good idea?

Thanks,

Jacob