mirror of
https://github.com/cloud-hypervisor/cloud-hypervisor.git
synced 2024-08-23 16:31:16 +00:00
135 lines
4.2 KiB
Rust
135 lines
4.2 KiB
Rust
|
// Copyright © 2022 Intel Corporation
|
||
|
//
|
||
|
// SPDX-License-Identifier: Apache-2.0
|
||
|
|
||
|
#![no_main]
|
||
|
|
||
|
use libfuzzer_sys::fuzz_target;
|
||
|
use seccompiler::SeccompAction;
|
||
|
use std::os::unix::io::{AsRawFd, FromRawFd};
|
||
|
use std::sync::Arc;
|
||
|
use virtio_devices::{VirtioDevice, VirtioInterrupt, VirtioInterruptType};
|
||
|
use virtio_queue::{Queue, QueueT};
|
||
|
use vm_memory::{bitmap::AtomicBitmap, Bytes, GuestAddress, GuestMemoryAtomic};
|
||
|
use vmm_sys_util::eventfd::{EventFd, EFD_NONBLOCK};
|
||
|
|
||
|
type GuestMemoryMmap = vm_memory::GuestMemoryMmap<AtomicBitmap>;
|
||
|
|
||
|
macro_rules! align {
|
||
|
($n:expr, $align:expr) => {{
|
||
|
(($n + $align - 1) / $align) * $align
|
||
|
}};
|
||
|
}
|
||
|
|
||
|
const QUEUE_DATA_SIZE: usize = 4;
|
||
|
const MEM_SIZE: usize = 1 * 1024 * 1024;
|
||
|
|
||
|
// Max entries in the queue.
|
||
|
const QUEUE_SIZE: u16 = 256;
|
||
|
// Descriptor table alignment
|
||
|
const DESC_TABLE_ALIGN_SIZE: u64 = 16;
|
||
|
// Avalable ring alignment
|
||
|
const AVAIL_RING_ALIGN_SIZE: u64 = 2;
|
||
|
// Used ring alignment
|
||
|
const USED_RING_ALIGN_SIZE: u64 = 4;
|
||
|
// Descriptor table size
|
||
|
const DESC_TABLE_SIZE: u64 = 16_u64 * QUEUE_SIZE as u64;
|
||
|
// Available ring size
|
||
|
const AVAIL_RING_SIZE: u64 = 6_u64 + 2 * QUEUE_SIZE as u64;
|
||
|
// Used ring size
|
||
|
const USED_RING_SIZE: u64 = 6_u64 + 8 * QUEUE_SIZE as u64;
|
||
|
|
||
|
// Guest memory gap
|
||
|
const GUEST_MEM_GAP: u64 = 1 * 1024 * 1024;
|
||
|
// Guest physical address for descriptor table.
|
||
|
const DESC_TABLE_ADDR: u64 = align!(MEM_SIZE as u64 + GUEST_MEM_GAP, DESC_TABLE_ALIGN_SIZE);
|
||
|
// Guest physical address for available ring
|
||
|
const AVAIL_RING_ADDR: u64 = align!(DESC_TABLE_ADDR + DESC_TABLE_SIZE, AVAIL_RING_ALIGN_SIZE);
|
||
|
// Guest physical address for used ring
|
||
|
const USED_RING_ADDR: u64 = align!(AVAIL_RING_ADDR + AVAIL_RING_SIZE, USED_RING_ALIGN_SIZE);
|
||
|
// Virtio-queue size in bytes
|
||
|
const QUEUE_BYTES_SIZE: usize = (USED_RING_ADDR + USED_RING_SIZE - DESC_TABLE_ADDR) as usize;
|
||
|
|
||
|
fuzz_target!(|bytes| {
|
||
|
if bytes.len() < (QUEUE_DATA_SIZE + QUEUE_BYTES_SIZE)
|
||
|
|| bytes.len() > (QUEUE_DATA_SIZE + QUEUE_BYTES_SIZE + MEM_SIZE)
|
||
|
{
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
let mut rng = virtio_devices::Rng::new(
|
||
|
"fuzzer_rng".to_owned(),
|
||
|
"/dev/urandom",
|
||
|
false,
|
||
|
SeccompAction::Allow,
|
||
|
EventFd::new(EFD_NONBLOCK).unwrap(),
|
||
|
)
|
||
|
.unwrap();
|
||
|
|
||
|
let queue_data = &bytes[..QUEUE_DATA_SIZE];
|
||
|
let queue_bytes = &bytes[QUEUE_DATA_SIZE..QUEUE_DATA_SIZE + QUEUE_BYTES_SIZE];
|
||
|
let mem_bytes = &bytes[QUEUE_DATA_SIZE + QUEUE_BYTES_SIZE..];
|
||
|
|
||
|
// Setup the virt queue with the input bytes
|
||
|
let q = setup_virt_queue(queue_data.try_into().unwrap());
|
||
|
|
||
|
// Setup the guest memory with the input bytes
|
||
|
let mem = GuestMemoryMmap::from_ranges(&[
|
||
|
(GuestAddress(0), MEM_SIZE),
|
||
|
(GuestAddress(DESC_TABLE_ADDR), QUEUE_BYTES_SIZE),
|
||
|
])
|
||
|
.unwrap();
|
||
|
if mem
|
||
|
.write_slice(queue_bytes, GuestAddress(DESC_TABLE_ADDR))
|
||
|
.is_err()
|
||
|
{
|
||
|
return;
|
||
|
}
|
||
|
if mem.write_slice(mem_bytes, GuestAddress(0 as u64)).is_err() {
|
||
|
return;
|
||
|
}
|
||
|
let guest_memory = GuestMemoryAtomic::new(mem);
|
||
|
|
||
|
let evt = EventFd::new(0).unwrap();
|
||
|
let queue_evt = unsafe { EventFd::from_raw_fd(libc::dup(evt.as_raw_fd())) };
|
||
|
|
||
|
// Kick the 'queue' event before activate the rng device
|
||
|
queue_evt.write(1).unwrap();
|
||
|
|
||
|
rng.activate(
|
||
|
guest_memory,
|
||
|
Arc::new(NoopVirtioInterrupt {}),
|
||
|
vec![(0, q, evt)],
|
||
|
)
|
||
|
.ok();
|
||
|
|
||
|
// Wait for the events to finish and rng device worker thread to return
|
||
|
rng.reset();
|
||
|
});
|
||
|
|
||
|
pub struct NoopVirtioInterrupt {}
|
||
|
|
||
|
impl VirtioInterrupt for NoopVirtioInterrupt {
|
||
|
fn trigger(&self, _int_type: VirtioInterruptType) -> std::result::Result<(), std::io::Error> {
|
||
|
Ok(())
|
||
|
}
|
||
|
}
|
||
|
|
||
|
fn setup_virt_queue(bytes: &[u8; QUEUE_DATA_SIZE]) -> Queue {
|
||
|
let mut q = Queue::new(QUEUE_SIZE).unwrap();
|
||
|
q.set_next_avail(bytes[0] as u16); // 'u8' is enough given the 'QUEUE_SIZE' is small
|
||
|
q.set_next_used(bytes[1] as u16);
|
||
|
q.set_event_idx(bytes[2] % 2 != 0);
|
||
|
q.set_size(bytes[3] as u16 % QUEUE_SIZE);
|
||
|
|
||
|
q.try_set_desc_table_address(GuestAddress(DESC_TABLE_ADDR))
|
||
|
.unwrap();
|
||
|
q.try_set_avail_ring_address(GuestAddress(AVAIL_RING_ADDR))
|
||
|
.unwrap();
|
||
|
q.try_set_used_ring_address(GuestAddress(USED_RING_ADDR))
|
||
|
.unwrap();
|
||
|
q.set_ready(true);
|
||
|
|
||
|
q
|
||
|
}
|