Comment 1 for bug 2010598

I think it's related to image size. Here's an image that mtools 4.0.32 fails on:

 $ fdisk -l foo.img
Disk foo.img: 69.89 MiB, 73285632 bytes, 143136 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x00000000

Device Boot Start End Sectors Size Id Type
foo.img1 * 63 143135 143073 69.9M 6 FAT16
 $ hexdump -C foo.img
00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
000001b0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 80 01 |................|
000001c0 01 00 06 0f 3f 8d 3f 00 00 00 e1 2e 02 00 00 00 |....?.?.........|
000001d0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
000001f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 55 aa |..............U.|
00000200 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
00007e00 eb 3c 90 4d 54 4f 4f 34 30 34 32 00 02 04 01 00 |.<.MTOO4042.....|
00007e10 02 00 02 00 00 f8 8c 00 3f 00 10 00 00 00 00 00 |........?.......|
00007e20 e1 2e 02 00 00 00 29 9d cd 3d 6d 4e 4f 20 4e 41 |......)..=mNO NA|
00007e30 4d 45 20 20 20 20 46 41 54 31 36 20 20 20 fa 31 |ME FAT16 .1|
00007e40 c0 8e d8 8e c0 fc b9 00 01 be 00 7c bf 00 80 f3 |...........|....|
00007e50 a5 ea 56 00 00 08 b8 01 02 bb 00 7c ba 80 00 b9 |..V........|....|
00007e60 01 00 cd 13 72 05 ea 00 7c 00 00 cd 19 00 00 00 |....r...|.......|
00007e70 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
00007ff0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 55 aa |..............U.|
00008000 f8 ff ff ff 00 00 00 00 00 00 00 00 00 00 00 00 |................|
00008010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
00019800 f8 ff ff ff 00 00 00 00 00 00 00 00 00 00 00 00 |................|
00019810 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
045e4000