diff --git a/crates/fuzzing/Cargo.toml b/crates/fuzzing/Cargo.toml index b0711d63df..c949a063e7 100644 --- a/crates/fuzzing/Cargo.toml +++ b/crates/fuzzing/Cargo.toml @@ -9,3 +9,9 @@ version = "0.1.0" # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html [dependencies] +arbitrary = "0.2.0" +binaryen = "0.8.1" +cranelift-codegen = "0.50.0" +cranelift-native = "0.50.0" +wasmparser = "0.42.1" +wasmtime-jit = { path = "../jit" } diff --git a/crates/fuzzing/src/generators.rs b/crates/fuzzing/src/generators.rs new file mode 100644 index 0000000000..e9ff714ce6 --- /dev/null +++ b/crates/fuzzing/src/generators.rs @@ -0,0 +1,29 @@ +//! Test case generators. +//! +//! Test case generators take raw, unstructured input from a fuzzer +//! (e.g. libFuzzer) and translate that into a structured test case (e.g. a +//! valid Wasm binary). +//! +//! These are generally implementations of the `Arbitrary` trait, or some +//! wrapper over an external tool, such that the wrapper implements the +//! `Arbitrary` trait for the wrapped external tool. + +use arbitrary::{Arbitrary, Unstructured}; + +/// A Wasm test case generator that is powered by Binaryen's `wasm-opt -ttf`. +pub struct WasmOptTtf { + /// The raw, encoded Wasm bytes. + pub wasm: Vec, +} + +impl Arbitrary for WasmOptTtf { + fn arbitrary(input: &mut U) -> Result + where + U: Unstructured + ?Sized, + { + let seed: Vec = Arbitrary::arbitrary(input)?; + let module = binaryen::tools::translate_to_fuzz_mvp(&seed); + let wasm = module.write(); + Ok(WasmOptTtf { wasm }) + } +} diff --git a/crates/fuzzing/src/lib.rs b/crates/fuzzing/src/lib.rs index e69de29bb2..c523a9bfbd 100644 --- a/crates/fuzzing/src/lib.rs +++ b/crates/fuzzing/src/lib.rs @@ -0,0 +1,2 @@ +pub mod generators; +pub mod oracles; diff --git a/crates/fuzzing/src/oracles.rs b/crates/fuzzing/src/oracles.rs new file mode 100644 index 0000000000..d47952dc8b --- /dev/null +++ b/crates/fuzzing/src/oracles.rs @@ -0,0 +1,66 @@ +//! Oracles. +//! +//! Oracles take a test case and determine whether we have a bug. For example, +//! one of the simplest oracles is to take a Wasm binary as our input test case, +//! validate and instantiate it, and (implicitly) check that no assertions +//! failed or segfaults happened. A more complicated oracle might compare the +//! result of executing a Wasm file with and without optimizations enabled, and +//! make sure that the two executions are observably identical. +//! +//! When an oracle finds a bug, it should report it to the fuzzing engine by +//! panicking. + +use cranelift_codegen::settings; +use std::cell::RefCell; +use std::collections::HashMap; +use std::rc::Rc; +use wasmtime_jit::{CompilationStrategy, CompiledModule, Compiler, NullResolver}; + +fn host_isa() -> Box { + let flag_builder = settings::builder(); + let isa_builder = cranelift_native::builder().expect("host machine is not a supported target"); + isa_builder.finish(settings::Flags::new(flag_builder)) +} + +/// Instantiate the Wasm buffer, and implicitly fail if we have an unexpected +/// panic or segfault or anything else that can be detected "passively". +/// +/// Performs initial validation, and returns early if the Wasm is invalid. +/// +/// You can control which compiler is used via passing a `CompilationStrategy`. +pub fn instantiate(wasm: &[u8], compilation_strategy: CompilationStrategy) { + if wasmparser::validate(wasm, None).is_err() { + return; + } + + let isa = host_isa(); + let mut compiler = Compiler::new(isa, compilation_strategy); + let mut imports_resolver = NullResolver {}; + + wasmtime_jit::instantiate( + &mut compiler, + wasm, + &mut imports_resolver, + Default::default(), + true, + ) + .expect("failed to instantiate valid Wasm!"); +} + +/// Compile the Wasm buffer, and implicitly fail if we have an unexpected +/// panic or segfault or anything else that can be detected "passively". +/// +/// Performs initial validation, and returns early if the Wasm is invalid. +/// +/// You can control which compiler is used via passing a `CompilationStrategy`. +pub fn compile(wasm: &[u8], compilation_strategy: CompilationStrategy) { + if wasmparser::validate(wasm, None).is_err() { + return; + } + + let isa = host_isa(); + let mut compiler = Compiler::new(isa, compilation_strategy); + let mut resolver = NullResolver {}; + let global_exports = Rc::new(RefCell::new(HashMap::new())); + let _ = CompiledModule::new(&mut compiler, wasm, &mut resolver, global_exports, false); +} diff --git a/fuzz/Cargo.toml b/fuzz/Cargo.toml index 15a63019dc..e0bc9ba101 100644 --- a/fuzz/Cargo.toml +++ b/fuzz/Cargo.toml @@ -9,14 +9,10 @@ publish = false cargo-fuzz = true [dependencies] -wasmtime-environ = { path = "../crates/environ" } +arbitrary = "0.2.0" +wasmtime-fuzzing = { path = "../crates/fuzzing" } wasmtime-jit = { path = "../crates/jit" } -cranelift-codegen = "0.50" -cranelift-wasm = "0.50" -cranelift-native = "0.50" libfuzzer-sys = { git = "https://github.com/rust-fuzz/libfuzzer-sys.git" } -wasmparser = { version = "0.39.2", default-features = false, features = ["core"] } -binaryen = "0.8.1" # Prevent this from interfering with workspaces [workspace] diff --git a/fuzz/fuzz_targets/compile.rs b/fuzz/fuzz_targets/compile.rs index 134facb43a..1f283b1ceb 100644 --- a/fuzz/fuzz_targets/compile.rs +++ b/fuzz/fuzz_targets/compile.rs @@ -2,49 +2,15 @@ extern crate libfuzzer_sys; -use cranelift_codegen::settings; use libfuzzer_sys::fuzz_target; -use std::cell::RefCell; -use std::collections::HashMap; -use std::rc::Rc; -use wasmparser::validate; -use wasmtime_jit::{CompilationStrategy, CompiledModule, Compiler, NullResolver}; +use wasmtime_fuzzing::oracles; +use wasmtime_jit::CompilationStrategy; fuzz_target!(|data: &[u8]| { - if validate(data, None).is_err() { - return; - } - let flag_builder = settings::builder(); - let isa_builder = cranelift_native::builder().unwrap_or_else(|_| { - panic!("host machine is not a supported target"); - }); - let isa = isa_builder.finish(settings::Flags::new(flag_builder)); - let mut compiler = Compiler::new(isa, CompilationStrategy::Cranelift); - let mut resolver = NullResolver {}; - let global_exports = Rc::new(RefCell::new(HashMap::new())); - let _compiled = - match CompiledModule::new(&mut compiler, data, &mut resolver, global_exports, false) { - Ok(x) => x, - Err(_) => return, - }; + oracles::compile(data, CompilationStrategy::Cranelift); }); #[cfg(feature = "lightbeam")] fuzz_target!(|data: &[u8]| { - if validate(data, None).is_err() { - return; - } - let flag_builder = settings::builder(); - let isa_builder = cranelift_native::builder().unwrap_or_else(|_| { - panic!("host machine is not a supported target"); - }); - let isa = isa_builder.finish(settings::Flags::new(flag_builder)); - let mut compiler = Compiler::new(isa, CompilationStrategy::Lightbeam); - let mut resolver = NullResolver {}; - let global_exports = Rc::new(RefCell::new(HashMap::new())); - let _compiled = - match CompiledModule::new(&mut compiler, data, &mut resolver, global_exports, false) { - Ok(x) => x, - Err(_) => return, - }; + oracles::compile(data, CompilationStrategy::Lightbeam); }); diff --git a/fuzz/fuzz_targets/instantiate.rs b/fuzz/fuzz_targets/instantiate.rs index 0c29cfc426..78d5cfe504 100644 --- a/fuzz/fuzz_targets/instantiate.rs +++ b/fuzz/fuzz_targets/instantiate.rs @@ -2,28 +2,10 @@ extern crate libfuzzer_sys; -use cranelift_codegen::settings; use libfuzzer_sys::fuzz_target; -use wasmparser::validate; -use wasmtime_jit::{instantiate, CompilationStrategy, Compiler, NullResolver}; +use wasmtime_fuzzing::oracles; +use wasmtime_jit::{CompilationStrategy}; fuzz_target!(|data: &[u8]| { - if validate(data, None).is_err() { - return; - } - let flag_builder = settings::builder(); - let isa_builder = cranelift_native::builder().unwrap_or_else(|_| { - panic!("host machine is not a supported target"); - }); - let isa = isa_builder.finish(settings::Flags::new(flag_builder)); - let mut compiler = Compiler::new(isa, CompilationStrategy::Auto); - let mut imports_resolver = NullResolver {}; - let _instance = instantiate( - &mut compiler, - data, - &mut imports_resolver, - Default::default(), - true, - ) - .unwrap(); + oracles::instantiate(data, CompilationStrategy::Auto); }); diff --git a/fuzz/fuzz_targets/instantiate_translated.rs b/fuzz/fuzz_targets/instantiate_translated.rs index 565b75cd13..ab1a17968d 100644 --- a/fuzz/fuzz_targets/instantiate_translated.rs +++ b/fuzz/fuzz_targets/instantiate_translated.rs @@ -2,26 +2,10 @@ extern crate libfuzzer_sys; -use cranelift_codegen::settings; use libfuzzer_sys::fuzz_target; -use wasmtime_jit::{instantiate, CompilationStrategy, Compiler, NullResolver}; +use wasmtime_fuzzing::{generators, oracles}; +use wasmtime_jit::CompilationStrategy; -fuzz_target!(|data: &[u8]| { - let binaryen_module = binaryen::tools::translate_to_fuzz_mvp(data); - let wasm = binaryen_module.write(); - let flag_builder = settings::builder(); - let isa_builder = cranelift_native::builder().unwrap_or_else(|_| { - panic!("host machine is not a supported target"); - }); - let isa = isa_builder.finish(settings::Flags::new(flag_builder)); - let mut compiler = Compiler::new(isa, CompilationStrategy::Auto); - let mut imports_resolver = NullResolver {}; - let _instance = instantiate( - &mut compiler, - &wasm, - &mut imports_resolver, - Default::default(), - true, - ) - .unwrap(); +fuzz_target!(|data: generators::WasmOptTtf| { + oracles::instantiate(&data.wasm, CompilationStrategy::Auto); });