4376cf2609
* Add differential fuzzing against V8 This commit adds a differential fuzzing target to Wasmtime along the lines of the wasmi and spec interpreters we already have, but with V8 instead. The intention here is that wasmi is unlikely to receive updates over time (e.g. for SIMD), and the spec interpreter is not suitable for fuzzing against in general due to its performance characteristics. The hope is that V8 is indeed appropriate to fuzz against because it's naturally receiving updates and it also is expected to have good performance. Here the `rusty_v8` crate is used which provides bindings to V8 as well as precompiled binaries by default. This matches exactly the use case we need and at least for now I think the `rusty_v8` crate will be maintained by the Deno folks as they continue to develop it. If it becomes an issue though maintaining we can evaluate other options to have differential fuzzing against. For now this commit enables the SIMD and bulk-memory feature of fuzz-target-generation which should enable them to get differentially-fuzzed with V8 in addition to the compilation fuzzing we're already getting. * Use weak linkage for GDB jit helpers This should help us deduplicate our symbol with other JIT runtimes, if any. For now this leans on some C helpers to define the weak linkage since Rust doesn't support that on stable yet. * Don't use rusty_v8 on MinGW They don't have precompiled libraries there. * Fix msvc build * Comment about execution
Fuzzing Infrastructure for Wasmtime
This crate provides test case generators and oracles for use with fuzzing.
These generators and oracles are generally independent of the fuzzing engine
that might be using them and driving the whole fuzzing process (e.g. libFuzzer
or AFL). As such, this crate does not contain any actual fuzz targets
itself. Those are generally just a couple lines of glue code that plug raw input
from (for example) libFuzzer into a generator, and then run one or more
oracles on the generated test case.
If you're looking for the actual fuzz target definitions we currently have, they
live in wasmtime/fuzz/fuzz_targets/* and are driven by cargo fuzz and
libFuzzer.