exFAT: Sometimes, icat only reads the first cluster of a file.

[HT-7]

From fls -l /dev/mmcblk0 (exFAT, 128K clusters):

++++ r/r * 19128323:	[redacted for privacy].zip	2021-01-30 14:40:16 (CET)	2021-01-30 00:00:00 (CET)	0000-00-00 00:00:00 (UTC)	2021-01-30 14:40:16 (CET)	25008503	0	0

When I run sudo icat /dev/mmcblk0p1 19128323 >>tmp.zip, the output file is 131072 bytes in size (which is 128 KiB), not 25008503 bytes.

The tmp.zip file starts with PK and contains binary data, so I presume the first 131072 bytes of the file were read correctly, but it doesn't read beyond that. But a MP4 file on the same device was read entirely.

I have no idea what causes this, nor how to reproduce this bug, but I will keep you updated when I find out more about this.