Weird cramfs header in a flashdump

[DrmnSamoLiu]

Hi, my apologies for opening a issue here for a question not really related to this project. But this repo is the only way I can find to contact people who knows cramfs....

So I was looking at a NAND flash dump I obtained from a device, and noticed there are cramfs in it. However, the header looks really weird and I hope to gain some insight from professionals here.

Above is the header I'm talking about.
From what I read here: https://www.kernel.org/doc/html/latest/filesystems/cramfs.html
The first 4 bytes after 0x28cd3d45 magic is the size of this fs, which is 0x10000 in this case (which is already weird).
Other headers also show strange values, especially all those fsid header. It results in this "file" command output:

All seems quite wrong to me, and it does not pass cramfsck for sure.

Do you have any idea how and why this happen?
My thoughts for now is that this is a NAND dump and NAND chips have bad block management going on, so this could be a potential cause.
Also NAND dumps are not always 100% correct, but I'm sure at least the header I posted above is not in a bad block, and I've dumped the NAND multiple times and the cramfs headers are the same.

[npitre]

You'd have to get the corresponding cramfs driver source code to figure that out. Maybe it was modified somehow.