crosvm/crosvm-fuzz/qcow_fuzzer.rs
Dennis Kempin a6e7d6f139 Enable compilation of fuzzing targets
Adds a fall-back to cros_fuzz when compiled without
fuzzing enabled that will just produce a main fn entrypoint
with the fuzzing code.
This allows the fuzzing code to be compiled, but won't produce
functional fuzzing binaries.

BUG=b:265829867
FIXES=b:244631591
TEST=crosvm CQ
cargo +nightly fuzz run --fuzz-dir crosvm-fuzz --features upstream-fuzz crosvm_block_fuzzer

Change-Id: Ib2602aab5c5373cb2a71dca0d8419640a00c6725
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/4167143
Commit-Queue: Dennis Kempin <denniskempin@google.com>
Reviewed-by: Zihan Chen <zihanchen@google.com>
2023-01-17 23:18:22 +00:00

45 lines
1.4 KiB
Rust

// Copyright 2019 The ChromiumOS Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#![cfg(not(test))]
#![no_main]
use std::io::Cursor;
use std::io::Read;
use std::io::Seek;
use std::io::SeekFrom;
use std::io::Write;
use std::mem::size_of;
use base::FileReadWriteAtVolatile;
use cros_fuzz::fuzz_target;
use data_model::VolatileSlice;
use disk::QcowFile;
// 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.
fuzz_target!(|bytes| {
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 max_nesting_depth = 10;
let mut disk_file = tempfile::tempfile().unwrap();
disk_file.write_all(&bytes[16..]).unwrap();
disk_file.seek(SeekFrom::Start(0)).unwrap();
if let Ok(mut qcow) = QcowFile::from(disk_file, max_nesting_depth) {
let mut mem = value.to_le_bytes().to_owned();
let vslice = VolatileSlice::new(&mut mem);
let _ = qcow.write_all_at_volatile(vslice, addr);
}
});
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)
}