f3read crash

```
Creating file 52.h2w ... OK!
Creating file 53.h2w ... OK!
Creating file 54.h2w ... OK!
Creating file 55.h2w ... Write failure: Input/output error

WARNING:
The write error above may be due to your memory card overheating
under constant, maximum write rate. You can test this hypothesis
touching your memory card. If it is hot, you can try f3write
again, once your card has cooled down, using parameter --max-write-rate=2048
to limit the maximum write rate to 2MB/s, or another suitable rate.

Creating file 56.h2w ... f3write: Can't create file /mnt/56.h2w: Input/output error
F3 read 8.0
Copyright (C) 2010 Digirati Internet LTDA.
This is free software; see the source for copying conditions.

SECTORS ok/corrupted/changed/overwritten
Validating file 1.h2w ... f3read: f3read.c:260: validate_file: Assertion `!fdatasync(fd)' failed.
./bin/flashtest: line 72: 23262 Aborted (core dumped) ${STDBUF[@]} f3read ${PP[@]} "$M"
```