fuzz_storvsp: remove last round of TODO: [use-arbitrary-input]

[mattkur]

Changes in storvsp fuzzer to increase code coverage in key areas and remove some TODO: [use-arbitrary-input].

[gurasinghMS]

data_in: (cdb.operation_code == ScsiOp::READ) as u8 could be a more concise way of doing this. (Credits: Copilot)

[mattkur]

Thanks

[gurasinghMS]

This is sounding quite repetitive. If possible, consider writing a generic function for this?

fn get_buffer<T: FromBytes>(u: &mut Unstructured<'_>) -> Result<T, arbitrary::Error> {
            let mut bytes = vec![0; size_of::<T>()];
            u.fill_buffer(&mut bytes)?;

            let val = T::mut_from_bytes(bytes.as_mut_slice())
                .map_err(|_| arbitrary::Error::IncorrectFormat)?;
           
            Ok(val)
}

[mattkur]

Thanks. I actually worked up a better way to do this (incoming), but this is helpful :)

[gurasinghMS]

Maybe have the match function return the bytes as well to move this outside the match function. Something like:

let bytes = match op {
        TargetScsiOp::Inquiry => {
                .....
                bytes
        }
};

scsi_req.payload[0..(bytes.len())].copy_from_slice(bytes.as_slice());

[mattkur]

Yeah, I tried this already. The bytes does not live long enough to be returned from the match (I guess I could figure out a way to copy them out, but I couldn't seem to get that to work)

[gurasinghMS]

Is this the correct type? TestWorker::start takes in : &ScsiController. &controller is of type &Arc<ScsiController>.

[mattkur]

hm, it complies? Let me check.