SPIRV-Tools/source/fuzz/fuzzer.cpp
Alastair Donaldson 96354f5047
spirv-fuzz: Fuzzer pass to merge blocks (#3097)
This change adds a transformation and associated fuzzer pass for
merging adjacent blocks in a module, re-using block merging code from
the optimizer.
2019-12-12 15:27:40 +00:00

250 lines
11 KiB
C++

// Copyright (c) 2019 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "source/fuzz/fuzzer.h"
#include <cassert>
#include <memory>
#include <sstream>
#include "fuzzer_pass_adjust_memory_operands_masks.h"
#include "source/fuzz/fact_manager.h"
#include "source/fuzz/fuzzer_context.h"
#include "source/fuzz/fuzzer_pass_add_dead_breaks.h"
#include "source/fuzz/fuzzer_pass_add_dead_continues.h"
#include "source/fuzz/fuzzer_pass_add_no_contraction_decorations.h"
#include "source/fuzz/fuzzer_pass_add_useful_constructs.h"
#include "source/fuzz/fuzzer_pass_adjust_function_controls.h"
#include "source/fuzz/fuzzer_pass_adjust_loop_controls.h"
#include "source/fuzz/fuzzer_pass_adjust_selection_controls.h"
#include "source/fuzz/fuzzer_pass_apply_id_synonyms.h"
#include "source/fuzz/fuzzer_pass_construct_composites.h"
#include "source/fuzz/fuzzer_pass_copy_objects.h"
#include "source/fuzz/fuzzer_pass_merge_blocks.h"
#include "source/fuzz/fuzzer_pass_obfuscate_constants.h"
#include "source/fuzz/fuzzer_pass_outline_functions.h"
#include "source/fuzz/fuzzer_pass_permute_blocks.h"
#include "source/fuzz/fuzzer_pass_split_blocks.h"
#include "source/fuzz/protobufs/spirvfuzz_protobufs.h"
#include "source/fuzz/pseudo_random_generator.h"
#include "source/opt/build_module.h"
#include "source/spirv_fuzzer_options.h"
#include "source/util/make_unique.h"
namespace spvtools {
namespace fuzz {
namespace {
const uint32_t kIdBoundGap = 100;
const uint32_t kTransformationLimit = 500;
const uint32_t kChanceOfApplyingAnotherPass = 85;
template <typename T>
void MaybeAddPass(
std::vector<std::unique_ptr<FuzzerPass>>* passes,
opt::IRContext* ir_context, FactManager* fact_manager,
FuzzerContext* fuzzer_context,
protobufs::TransformationSequence* transformation_sequence_out) {
if (fuzzer_context->ChooseEven()) {
passes->push_back(MakeUnique<T>(ir_context, fact_manager, fuzzer_context,
transformation_sequence_out));
}
}
} // namespace
struct Fuzzer::Impl {
explicit Impl(spv_target_env env, uint32_t random_seed,
bool validate_after_each_pass)
: target_env(env),
seed(random_seed),
validate_after_each_fuzzer_pass(validate_after_each_pass) {}
bool ApplyPassAndCheckValidity(FuzzerPass* pass,
const opt::IRContext& ir_context,
const spvtools::SpirvTools& tools) const;
const spv_target_env target_env; // Target environment.
const uint32_t seed; // Seed for random number generator.
bool validate_after_each_fuzzer_pass; // Determines whether the validator
// should be invoked after every fuzzer pass.
MessageConsumer consumer; // Message consumer.
};
Fuzzer::Fuzzer(spv_target_env env, uint32_t seed,
bool validate_after_each_fuzzer_pass)
: impl_(MakeUnique<Impl>(env, seed, validate_after_each_fuzzer_pass)) {}
Fuzzer::~Fuzzer() = default;
void Fuzzer::SetMessageConsumer(MessageConsumer c) {
impl_->consumer = std::move(c);
}
bool Fuzzer::Impl::ApplyPassAndCheckValidity(
FuzzerPass* pass, const opt::IRContext& ir_context,
const spvtools::SpirvTools& tools) const {
pass->Apply();
if (validate_after_each_fuzzer_pass) {
std::vector<uint32_t> binary_to_validate;
ir_context.module()->ToBinary(&binary_to_validate, false);
if (!tools.Validate(&binary_to_validate[0], binary_to_validate.size())) {
consumer(SPV_MSG_INFO, nullptr, {},
"Binary became invalid during fuzzing (set a breakpoint to "
"inspect); stopping.");
return false;
}
}
return true;
}
Fuzzer::FuzzerResultStatus Fuzzer::Run(
const std::vector<uint32_t>& binary_in,
const protobufs::FactSequence& initial_facts,
std::vector<uint32_t>* binary_out,
protobufs::TransformationSequence* transformation_sequence_out) const {
// Check compatibility between the library version being linked with and the
// header files being used.
GOOGLE_PROTOBUF_VERIFY_VERSION;
spvtools::SpirvTools tools(impl_->target_env);
tools.SetMessageConsumer(impl_->consumer);
if (!tools.IsValid()) {
impl_->consumer(SPV_MSG_ERROR, nullptr, {},
"Failed to create SPIRV-Tools interface; stopping.");
return Fuzzer::FuzzerResultStatus::kFailedToCreateSpirvToolsInterface;
}
// Initial binary should be valid.
if (!tools.Validate(&binary_in[0], binary_in.size())) {
impl_->consumer(SPV_MSG_ERROR, nullptr, {},
"Initial binary is invalid; stopping.");
return Fuzzer::FuzzerResultStatus::kInitialBinaryInvalid;
}
// Build the module from the input binary.
std::unique_ptr<opt::IRContext> ir_context = BuildModule(
impl_->target_env, impl_->consumer, binary_in.data(), binary_in.size());
assert(ir_context);
// Make a PRNG from the seed passed to the fuzzer on creation.
PseudoRandomGenerator random_generator(impl_->seed);
// The fuzzer will introduce new ids into the module. The module's id bound
// gives the smallest id that can be used for this purpose. We add an offset
// to this so that there is a sizeable gap between the ids used in the
// original module and the ids used for fuzzing, as a readability aid.
//
// TODO(https://github.com/KhronosGroup/SPIRV-Tools/issues/2541) consider the
// case where the maximum id bound is reached.
auto minimum_fresh_id = ir_context->module()->id_bound() + kIdBoundGap;
FuzzerContext fuzzer_context(&random_generator, minimum_fresh_id);
FactManager fact_manager;
fact_manager.AddFacts(impl_->consumer, initial_facts, ir_context.get());
// Add some essential ingredients to the module if they are not already
// present, such as boolean constants.
FuzzerPassAddUsefulConstructs add_useful_constructs(
ir_context.get(), &fact_manager, &fuzzer_context,
transformation_sequence_out);
if (!impl_->ApplyPassAndCheckValidity(&add_useful_constructs, *ir_context,
tools)) {
return Fuzzer::FuzzerResultStatus::kFuzzerPassLedToInvalidModule;
}
// Apply some semantics-preserving passes.
std::vector<std::unique_ptr<FuzzerPass>> passes;
while (passes.empty()) {
MaybeAddPass<FuzzerPassAddDeadBreaks>(&passes, ir_context.get(),
&fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassAddDeadContinues>(&passes, ir_context.get(),
&fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassApplyIdSynonyms>(&passes, ir_context.get(),
&fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassConstructComposites>(&passes, ir_context.get(),
&fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassCopyObjects>(&passes, ir_context.get(),
&fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassMergeBlocks>(&passes, ir_context.get(),
&fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassObfuscateConstants>(&passes, ir_context.get(),
&fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassOutlineFunctions>(&passes, ir_context.get(),
&fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassPermuteBlocks>(&passes, ir_context.get(),
&fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassSplitBlocks>(&passes, ir_context.get(),
&fact_manager, &fuzzer_context,
transformation_sequence_out);
}
bool is_first = true;
while (static_cast<uint32_t>(
transformation_sequence_out->transformation_size()) <
kTransformationLimit &&
(is_first ||
fuzzer_context.ChoosePercentage(kChanceOfApplyingAnotherPass))) {
is_first = false;
if (!impl_->ApplyPassAndCheckValidity(
passes[fuzzer_context.RandomIndex(passes)].get(), *ir_context,
tools)) {
return Fuzzer::FuzzerResultStatus::kFuzzerPassLedToInvalidModule;
}
}
// Now apply some passes that it does not make sense to apply repeatedly,
// as they do not unlock other passes.
std::vector<std::unique_ptr<FuzzerPass>> final_passes;
MaybeAddPass<FuzzerPassAdjustFunctionControls>(
&final_passes, ir_context.get(), &fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassAdjustLoopControls>(&final_passes, ir_context.get(),
&fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassAdjustMemoryOperandsMasks>(
&final_passes, ir_context.get(), &fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassAdjustSelectionControls>(
&final_passes, ir_context.get(), &fact_manager, &fuzzer_context,
transformation_sequence_out);
MaybeAddPass<FuzzerPassAddNoContractionDecorations>(
&final_passes, ir_context.get(), &fact_manager, &fuzzer_context,
transformation_sequence_out);
for (auto& pass : final_passes) {
if (!impl_->ApplyPassAndCheckValidity(pass.get(), *ir_context, tools)) {
return Fuzzer::FuzzerResultStatus::kFuzzerPassLedToInvalidModule;
}
}
// Encode the module as a binary.
ir_context->module()->ToBinary(binary_out, false);
return Fuzzer::FuzzerResultStatus::kComplete;
}
} // namespace fuzz
} // namespace spvtools