blob: f76e5d0aed190e9259fb2b5aad80ef8beaf41586 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
// Copyright 2019 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 qcow::QcowFile;
use sys_util::SharedMemory;
use std::fs::File;
use std::io::{Cursor, Read, Seek, SeekFrom, Write};
use std::mem::size_of;
use std::panic;
use std::process;
use std::slice;
// Take the first 64 bits of data as an address and the next 64 bits as data to
// store there. The rest of the data is used as a qcow image.
#[export_name = "LLVMFuzzerTestOneInput"]
pub fn test_one_input(data: *const u8, size: usize) -> i32 {
// We cannot unwind past ffi boundaries.
panic::catch_unwind(|| {
// Safe because the libfuzzer runtime will guarantee that `data` is at least
// `size` bytes long and that it will be valid for the lifetime of this
// function.
let bytes = unsafe { slice::from_raw_parts(data, size) };
if bytes.len() < 16 {
// Need an address and data, each are 8 bytes.
return;
}
let mut disk_image = Cursor::new(bytes);
let addr = read_u64(&mut disk_image);
let value = read_u64(&mut disk_image);
let shm = SharedMemory::anon().unwrap();
let mut disk_file: File = shm.into();
disk_file.write_all(&bytes[16..]).unwrap();
disk_file.seek(SeekFrom::Start(0)).unwrap();
if let Ok(mut qcow) = QcowFile::from(disk_file) {
if qcow.seek(SeekFrom::Start(addr)).is_ok() {
let _ = qcow.write_all(&value.to_le_bytes());
}
}
})
.err()
.map(|_| process::abort());
0
}
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)
}
|