Why does badblocks check more blocks than the disk has?

badblocks finds 80,475,544 bad blocks.

Code:dumpe2fs -b returns no blocks.

Code: e2fsck -L BadBlockList returns Quote:

Bad block xxxx out of range; ignored

for every entry in BadBlockList.

Code: dumpe2fs -x returns Quote:

Block count 29,304,950

.

The lowest block in BadBlockList is 36,744,256.

I see a problem: Code: badblocks reports Quote:

Checking blocks 0 to 117219799

- way too many. Where does it get this number?