Segmentation fault when using “-s max”

[Bill Yikes]

I'm starting with a 2.5gb image of a TomTom device which was created using dd. There is no partition table, so the vfat filesystem begins on the very first sector.

$ dd if=/dev/sdd of=image_file_2.5gb.dd

This is a migration to a 4gb sd card. So I used fdisk to see the full size of the target media, and allocated a file to match:

$ fallocate -l 4008706048 image_file_4gb.img

Copied the contents bit-for-bit:

$ dd if=image_file_2.5gb.dd of=image_file_4gb.img conv=notrunc

Finally the vfat filesystem thereon must be stretched:

$ fatresize -s max image_file_4gb.img
fatresize 1.1.0 (20201114)
part(start=0, end=7829503, length=7829504)
Segmentation fault

It resembles this bug:

https://github.com/ya-mouse/fatresize/issues/6

but that bug was supposedly fixed 3 yrs prior to version 1.1.0.

Workaround:

It's worth noting that the segfault can be avoided if the smaller image is copied to a larger SD card, and “fatresize -s max” is run on the unmounted device (e.g. /dev/sdd) instead of running it on an image file.