v8/test/fuzzer/wasm.cc
Clemens Backes a024ea4ba7 [wasm][fuzzer] Fix data race when setting flags
Fuzzers are executed in their own process, so instead of resetting flags
after execution, we can just keep the flag values.
This CL introduces a shared function to enable all staged features,
without ever resetting the value. This fixes a data race.

R=ahaas@chromium.org

Bug: v8:10979
Change-Id: I82ea35b887841850edd8b394a3644cf8df1e3bf8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2449969
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70320}
2020-10-05 16:31:11 +00:00

72 lines
2.5 KiB
C++

// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <limits.h>
#include <stddef.h>
#include <stdint.h>
#include "include/v8.h"
#include "src/execution/isolate-inl.h"
#include "src/heap/factory.h"
#include "src/objects/objects-inl.h"
#include "src/wasm/wasm-engine.h"
#include "src/wasm/wasm-feature-flags.h"
#include "src/wasm/wasm-module.h"
#include "test/common/wasm/flag-utils.h"
#include "test/common/wasm/wasm-module-runner.h"
#include "test/fuzzer/fuzzer-support.h"
#include "test/fuzzer/wasm-fuzzer-common.h"
namespace i = v8::internal;
extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
// We explicitly enable staged WebAssembly features here to increase fuzzer
// coverage. For libfuzzer fuzzers it is not possible that the fuzzer enables
// the flag by itself.
i::wasm::fuzzer::OneTimeEnableStagedWasmFeatures();
// We reduce the maximum memory size and table size of WebAssembly instances
// to avoid OOMs in the fuzzer.
i::FLAG_wasm_max_mem_pages = 32;
i::FLAG_wasm_max_table_size = 100;
v8_fuzzer::FuzzerSupport* support = v8_fuzzer::FuzzerSupport::Get();
v8::Isolate* isolate = support->GetIsolate();
i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
// Clear any pending exceptions from a prior run.
if (i_isolate->has_pending_exception()) {
i_isolate->clear_pending_exception();
}
v8::Isolate::Scope isolate_scope(isolate);
v8::HandleScope handle_scope(isolate);
v8::Context::Scope context_scope(support->GetContext());
v8::TryCatch try_catch(isolate);
i::wasm::testing::SetupIsolateForWasmModule(i_isolate);
i::wasm::ModuleWireBytes wire_bytes(data, data + size);
i::HandleScope scope(i_isolate);
i::wasm::ErrorThrower thrower(i_isolate, "wasm fuzzer");
i::Handle<i::WasmModuleObject> module_object;
auto enabled_features = i::wasm::WasmFeatures::FromIsolate(i_isolate);
bool compiles =
i_isolate->wasm_engine()
->SyncCompile(i_isolate, enabled_features, &thrower, wire_bytes)
.ToHandle(&module_object);
if (i::FLAG_wasm_fuzzer_gen_test) {
i::wasm::fuzzer::GenerateTestCase(i_isolate, wire_bytes, compiles);
}
if (compiles) {
i::wasm::fuzzer::InterpretAndExecuteModule(i_isolate, module_object);
}
// Pump the message loop and run micro tasks, e.g. GC finalization tasks.
support->PumpMessageLoop(v8::platform::MessageLoopBehavior::kDoNotWait);
isolate->PerformMicrotaskCheckpoint();
return 0;
}