crosvm/crosvm-fuzz/block_fuzzer.rs
Dennis Kempin 4fea399df9 Reformat imports
crosvm is switching the import style to use one import per line.
While more verbose, this will greatly reduce the occurence of merge
conflicts going forward.

Note: This is using a nightly feature of rustfmt. So it's a one-off
re-format only. We are considering adding a nightly toolchain to
enable the feature permanently.

BUG=b:239937122
TEST=CQ

Change-Id: Id2dd4dbdc0adfc4f8f3dd1d09da1daafa2a39992
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3784345
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Tested-by: Dennis Kempin <denniskempin@google.com>
Commit-Queue: Dennis Kempin <denniskempin@google.com>
2022-07-28 00:15:50 +00:00

114 lines
3.1 KiB
Rust

// Copyright 2018 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#![no_main]
use std::io::Cursor;
use std::io::Read;
use std::io::Seek;
use std::io::SeekFrom;
use std::mem::size_of;
use std::sync::atomic::AtomicUsize;
use std::sync::Arc;
use base::Event;
use cros_fuzz::fuzz_target;
use devices::virtio::base_features;
use devices::virtio::Block;
use devices::virtio::Interrupt;
use devices::virtio::Queue;
use devices::virtio::VirtioDevice;
use devices::IrqLevelEvent;
use hypervisor::ProtectionType;
use vm_memory::GuestAddress;
use vm_memory::GuestMemory;
const MEM_SIZE: u64 = 256 * 1024 * 1024;
const DESC_SIZE: u64 = 16; // Bytes in one virtio descriptor.
const QUEUE_SIZE: u16 = 16; // Max entries in the queue.
const CMD_SIZE: usize = 16; // Bytes in the command.
fuzz_target!(|bytes| {
let size_u64 = size_of::<u64>();
let mem = GuestMemory::new(&[(GuestAddress(0), MEM_SIZE)]).unwrap();
// The fuzz data is interpreted as:
// starting index 8 bytes
// command location 8 bytes
// command 16 bytes
// descriptors circular buffer 16 bytes * 3
if bytes.len() < 4 * size_u64 {
// Need an index to start.
return;
}
let mut data_image = Cursor::new(bytes);
let first_index = read_u64(&mut data_image);
if first_index > MEM_SIZE / DESC_SIZE {
return;
}
let first_offset = first_index * DESC_SIZE;
if first_offset as usize + size_u64 > bytes.len() {
return;
}
let command_addr = read_u64(&mut data_image);
if command_addr > MEM_SIZE - CMD_SIZE as u64 {
return;
}
if mem
.write_all_at_addr(
&bytes[2 * size_u64..(2 * size_u64) + CMD_SIZE],
GuestAddress(command_addr as u64),
)
.is_err()
{
return;
}
data_image.seek(SeekFrom::Start(first_offset)).unwrap();
let desc_table = read_u64(&mut data_image);
if mem
.write_all_at_addr(&bytes[32..], GuestAddress(desc_table as u64))
.is_err()
{
return;
}
let mut q = Queue::new(QUEUE_SIZE);
q.set_ready(true);
q.set_size(QUEUE_SIZE / 2);
q.max_size = QUEUE_SIZE;
let queue_evts: Vec<Event> = vec![Event::new().unwrap()];
let queue_evt = queue_evts[0].try_clone().unwrap();
let features = base_features(ProtectionType::Unprotected);
let disk_file = tempfile::tempfile().unwrap();
let mut block =
Block::new(features, Box::new(disk_file), false, true, 512, None, None).unwrap();
block.activate(
mem,
Interrupt::new(
Arc::new(AtomicUsize::new(0)),
IrqLevelEvent::new().unwrap(),
None, // msix_config
0xFFFF, // VIRTIO_MSI_NO_VECTOR
),
vec![q],
queue_evts,
);
queue_evt.write(77).unwrap(); // Rings the doorbell, any byte will do.
});
fn read_u64<T: Read>(readable: &mut T) -> u64 {
let mut buf = [0u8; size_of::<u64>()];
readable.read_exact(&mut buf[..]).unwrap();
u64::from_le_bytes(buf)
}