coreutils/fuzz/fuzz_targets/fuzz_expr.rs
2023-11-09 17:40:27 +01:00

108 lines
3.3 KiB
Rust

// This file is part of the uutils coreutils package.
//
// For the full copyright and license information, please view the LICENSE
// file that was distributed with this source code.
// spell-checker:ignore parens
#![no_main]
use libfuzzer_sys::fuzz_target;
use uu_expr::uumain;
use rand::seq::SliceRandom;
use rand::Rng;
use std::{env, ffi::OsString};
mod fuzz_common;
use crate::fuzz_common::{compare_result, generate_and_run_uumain, run_gnu_cmd};
static CMD_PATH: &str = "expr";
fn generate_random_string(max_length: usize) -> String {
let mut rng = rand::thread_rng();
let valid_utf8: Vec<char> = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
.chars()
.collect();
let invalid_utf8 = [0xC3, 0x28]; // Invalid UTF-8 sequence
let mut result = String::new();
for _ in 0..rng.gen_range(1..=max_length) {
if rng.gen_bool(0.9) {
let ch = valid_utf8.choose(&mut rng).unwrap();
result.push(*ch);
} else {
let ch = invalid_utf8.choose(&mut rng).unwrap();
if let Some(c) = char::from_u32(*ch as u32) {
result.push(c);
}
}
}
result
}
fn generate_expr(max_depth: u32) -> String {
let mut rng = rand::thread_rng();
let ops = ["+", "-", "*", "/", "%", "<", ">", "=", "&", "|"];
let mut expr = String::new();
let mut depth = 0;
let mut last_was_operator = false;
while depth <= max_depth {
if last_was_operator || depth == 0 {
// Add a number
expr.push_str(&rng.gen_range(1..=100).to_string());
last_was_operator = false;
} else {
// 90% chance to add an operator followed by a number
if rng.gen_bool(0.9) {
let op = *ops.choose(&mut rng).unwrap();
expr.push_str(&format!(" {} ", op));
last_was_operator = true;
}
// 10% chance to add a random string (potentially invalid syntax)
else {
let random_str = generate_random_string(rng.gen_range(1..=10));
expr.push_str(&random_str);
last_was_operator = false;
}
}
depth += 1;
}
// Ensure the expression ends with a number if it ended with an operator
if last_was_operator {
expr.push_str(&rng.gen_range(1..=100).to_string());
}
expr
}
fuzz_target!(|_data: &[u8]| {
let mut rng = rand::thread_rng();
let expr = generate_expr(rng.gen_range(0..=20));
let mut args = vec![OsString::from("expr")];
args.extend(expr.split_whitespace().map(OsString::from));
// Use C locale to avoid false positives, like in https://github.com/uutils/coreutils/issues/5378,
// because uutils expr doesn't support localization yet
// TODO remove once uutils expr supports localization
env::set_var("LC_COLLATE", "C");
let (rust_stdout, rust_stderr, uumain_exit_code) = generate_and_run_uumain(&args, uumain);
let (gnu_stdout, gnu_stderr, gnu_exit_code) =
run_gnu_cmd(CMD_PATH, &args[1..], false).unwrap_or_else(|e| e);
compare_result(
"expr",
&format!("{:?}", &args[1..]),
&rust_stdout,
&gnu_stdout,
&rust_stderr,
&gnu_stderr,
uumain_exit_code,
gnu_exit_code,
false, // Set to true if you want to fail on stderr diff
);
});