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410 lines
20 KiB
410 lines
20 KiB
// Copyright (c) 2019 Google LLC
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#include "source/fuzz/fuzzer.h"
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#include <cassert>
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#include <memory>
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#include <numeric>
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#include <sstream>
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#include "source/fuzz/fact_manager/fact_manager.h"
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#include "source/fuzz/fuzzer_context.h"
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#include "source/fuzz/fuzzer_pass_add_access_chains.h"
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#include "source/fuzz/fuzzer_pass_add_bit_instruction_synonyms.h"
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#include "source/fuzz/fuzzer_pass_add_composite_extract.h"
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#include "source/fuzz/fuzzer_pass_add_composite_inserts.h"
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#include "source/fuzz/fuzzer_pass_add_composite_types.h"
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#include "source/fuzz/fuzzer_pass_add_copy_memory.h"
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#include "source/fuzz/fuzzer_pass_add_dead_blocks.h"
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#include "source/fuzz/fuzzer_pass_add_dead_breaks.h"
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#include "source/fuzz/fuzzer_pass_add_dead_continues.h"
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#include "source/fuzz/fuzzer_pass_add_equation_instructions.h"
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#include "source/fuzz/fuzzer_pass_add_function_calls.h"
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#include "source/fuzz/fuzzer_pass_add_global_variables.h"
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#include "source/fuzz/fuzzer_pass_add_image_sample_unused_components.h"
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#include "source/fuzz/fuzzer_pass_add_loads.h"
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#include "source/fuzz/fuzzer_pass_add_local_variables.h"
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#include "source/fuzz/fuzzer_pass_add_loop_preheaders.h"
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#include "source/fuzz/fuzzer_pass_add_loops_to_create_int_constant_synonyms.h"
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#include "source/fuzz/fuzzer_pass_add_no_contraction_decorations.h"
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#include "source/fuzz/fuzzer_pass_add_opphi_synonyms.h"
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#include "source/fuzz/fuzzer_pass_add_parameters.h"
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#include "source/fuzz/fuzzer_pass_add_relaxed_decorations.h"
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#include "source/fuzz/fuzzer_pass_add_stores.h"
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#include "source/fuzz/fuzzer_pass_add_synonyms.h"
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#include "source/fuzz/fuzzer_pass_add_vector_shuffle_instructions.h"
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#include "source/fuzz/fuzzer_pass_adjust_branch_weights.h"
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#include "source/fuzz/fuzzer_pass_adjust_function_controls.h"
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#include "source/fuzz/fuzzer_pass_adjust_loop_controls.h"
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#include "source/fuzz/fuzzer_pass_adjust_memory_operands_masks.h"
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#include "source/fuzz/fuzzer_pass_adjust_selection_controls.h"
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#include "source/fuzz/fuzzer_pass_apply_id_synonyms.h"
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#include "source/fuzz/fuzzer_pass_construct_composites.h"
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#include "source/fuzz/fuzzer_pass_copy_objects.h"
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#include "source/fuzz/fuzzer_pass_donate_modules.h"
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#include "source/fuzz/fuzzer_pass_duplicate_regions_with_selections.h"
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#include "source/fuzz/fuzzer_pass_expand_vector_reductions.h"
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#include "source/fuzz/fuzzer_pass_flatten_conditional_branches.h"
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#include "source/fuzz/fuzzer_pass_inline_functions.h"
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#include "source/fuzz/fuzzer_pass_interchange_signedness_of_integer_operands.h"
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#include "source/fuzz/fuzzer_pass_interchange_zero_like_constants.h"
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#include "source/fuzz/fuzzer_pass_invert_comparison_operators.h"
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#include "source/fuzz/fuzzer_pass_make_vector_operations_dynamic.h"
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#include "source/fuzz/fuzzer_pass_merge_blocks.h"
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#include "source/fuzz/fuzzer_pass_merge_function_returns.h"
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#include "source/fuzz/fuzzer_pass_mutate_pointers.h"
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#include "source/fuzz/fuzzer_pass_obfuscate_constants.h"
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#include "source/fuzz/fuzzer_pass_outline_functions.h"
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#include "source/fuzz/fuzzer_pass_permute_blocks.h"
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#include "source/fuzz/fuzzer_pass_permute_function_parameters.h"
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#include "source/fuzz/fuzzer_pass_permute_instructions.h"
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#include "source/fuzz/fuzzer_pass_permute_phi_operands.h"
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#include "source/fuzz/fuzzer_pass_propagate_instructions_down.h"
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#include "source/fuzz/fuzzer_pass_propagate_instructions_up.h"
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#include "source/fuzz/fuzzer_pass_push_ids_through_variables.h"
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#include "source/fuzz/fuzzer_pass_replace_adds_subs_muls_with_carrying_extended.h"
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#include "source/fuzz/fuzzer_pass_replace_branches_from_dead_blocks_with_exits.h"
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#include "source/fuzz/fuzzer_pass_replace_copy_memories_with_loads_stores.h"
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#include "source/fuzz/fuzzer_pass_replace_copy_objects_with_stores_loads.h"
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#include "source/fuzz/fuzzer_pass_replace_irrelevant_ids.h"
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#include "source/fuzz/fuzzer_pass_replace_linear_algebra_instructions.h"
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#include "source/fuzz/fuzzer_pass_replace_loads_stores_with_copy_memories.h"
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#include "source/fuzz/fuzzer_pass_replace_opphi_ids_from_dead_predecessors.h"
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#include "source/fuzz/fuzzer_pass_replace_opselects_with_conditional_branches.h"
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#include "source/fuzz/fuzzer_pass_replace_parameter_with_global.h"
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#include "source/fuzz/fuzzer_pass_replace_params_with_struct.h"
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#include "source/fuzz/fuzzer_pass_split_blocks.h"
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#include "source/fuzz/fuzzer_pass_swap_commutable_operands.h"
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#include "source/fuzz/fuzzer_pass_swap_conditional_branch_operands.h"
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#include "source/fuzz/fuzzer_pass_toggle_access_chain_instruction.h"
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#include "source/fuzz/fuzzer_pass_wrap_regions_in_selections.h"
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#include "source/fuzz/pass_management/repeated_pass_manager.h"
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#include "source/fuzz/pass_management/repeated_pass_manager_looped_with_recommendations.h"
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#include "source/fuzz/pass_management/repeated_pass_manager_random_with_recommendations.h"
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#include "source/fuzz/pass_management/repeated_pass_manager_simple.h"
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#include "source/fuzz/pass_management/repeated_pass_recommender_standard.h"
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#include "source/fuzz/protobufs/spirvfuzz_protobufs.h"
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#include "source/fuzz/transformation_context.h"
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#include "source/opt/build_module.h"
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#include "source/spirv_fuzzer_options.h"
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#include "source/util/make_unique.h"
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namespace spvtools {
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namespace fuzz {
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namespace {
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const uint32_t kIdBoundGap = 100;
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} // namespace
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Fuzzer::Fuzzer(spv_target_env target_env, MessageConsumer consumer,
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const std::vector<uint32_t>& binary_in,
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const protobufs::FactSequence& initial_facts,
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const std::vector<fuzzerutil::ModuleSupplier>& donor_suppliers,
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std::unique_ptr<RandomGenerator> random_generator,
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bool enable_all_passes,
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RepeatedPassStrategy repeated_pass_strategy,
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bool validate_after_each_fuzzer_pass,
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spv_validator_options validator_options)
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: target_env_(target_env),
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consumer_(std::move(consumer)),
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binary_in_(binary_in),
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initial_facts_(initial_facts),
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donor_suppliers_(donor_suppliers),
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random_generator_(std::move(random_generator)),
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enable_all_passes_(enable_all_passes),
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repeated_pass_strategy_(repeated_pass_strategy),
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validate_after_each_fuzzer_pass_(validate_after_each_fuzzer_pass),
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validator_options_(validator_options),
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num_repeated_passes_applied_(0),
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ir_context_(nullptr),
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fuzzer_context_(nullptr),
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transformation_context_(nullptr),
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transformation_sequence_out_() {}
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Fuzzer::~Fuzzer() = default;
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template <typename FuzzerPassT, typename... Args>
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void Fuzzer::MaybeAddRepeatedPass(uint32_t percentage_chance_of_adding_pass,
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RepeatedPassInstances* pass_instances,
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Args&&... extra_args) {
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if (enable_all_passes_ ||
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fuzzer_context_->ChoosePercentage(percentage_chance_of_adding_pass)) {
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pass_instances->SetPass(MakeUnique<FuzzerPassT>(
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ir_context_.get(), transformation_context_.get(), fuzzer_context_.get(),
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&transformation_sequence_out_, std::forward<Args>(extra_args)...));
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}
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}
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template <typename FuzzerPassT, typename... Args>
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void Fuzzer::MaybeAddFinalPass(std::vector<std::unique_ptr<FuzzerPass>>* passes,
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Args&&... extra_args) {
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if (enable_all_passes_ || fuzzer_context_->ChooseEven()) {
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passes->push_back(MakeUnique<FuzzerPassT>(
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ir_context_.get(), transformation_context_.get(), fuzzer_context_.get(),
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&transformation_sequence_out_, std::forward<Args>(extra_args)...));
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}
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}
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bool Fuzzer::ApplyPassAndCheckValidity(FuzzerPass* pass) const {
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pass->Apply();
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return !validate_after_each_fuzzer_pass_ ||
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fuzzerutil::IsValidAndWellFormed(ir_context_.get(), validator_options_,
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consumer_);
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}
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Fuzzer::FuzzerResult Fuzzer::Run() {
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// Check compatibility between the library version being linked with and the
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// header files being used.
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GOOGLE_PROTOBUF_VERIFY_VERSION;
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assert(ir_context_ == nullptr && fuzzer_context_ == nullptr &&
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transformation_context_ == nullptr &&
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transformation_sequence_out_.transformation_size() == 0 &&
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"'Run' must not be invoked more than once.");
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spvtools::SpirvTools tools(target_env_);
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tools.SetMessageConsumer(consumer_);
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if (!tools.IsValid()) {
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consumer_(SPV_MSG_ERROR, nullptr, {},
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"Failed to create SPIRV-Tools interface; stopping.");
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return {Fuzzer::FuzzerResultStatus::kFailedToCreateSpirvToolsInterface,
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std::vector<uint32_t>(), protobufs::TransformationSequence()};
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}
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// Initial binary should be valid.
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if (!tools.Validate(&binary_in_[0], binary_in_.size(), validator_options_)) {
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consumer_(SPV_MSG_ERROR, nullptr, {},
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"Initial binary is invalid; stopping.");
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return {Fuzzer::FuzzerResultStatus::kInitialBinaryInvalid,
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std::vector<uint32_t>(), protobufs::TransformationSequence()};
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}
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// Build the module from the input binary.
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ir_context_ =
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BuildModule(target_env_, consumer_, binary_in_.data(), binary_in_.size());
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assert(ir_context_);
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// The fuzzer will introduce new ids into the module. The module's id bound
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// gives the smallest id that can be used for this purpose. We add an offset
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// to this so that there is a sizeable gap between the ids used in the
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// original module and the ids used for fuzzing, as a readability aid.
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//
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// TODO(https://github.com/KhronosGroup/SPIRV-Tools/issues/2541) consider the
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// case where the maximum id bound is reached.
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auto minimum_fresh_id = ir_context_->module()->id_bound() + kIdBoundGap;
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fuzzer_context_ =
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MakeUnique<FuzzerContext>(random_generator_.get(), minimum_fresh_id);
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transformation_context_ = MakeUnique<TransformationContext>(
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MakeUnique<FactManager>(ir_context_.get()), validator_options_);
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transformation_context_->GetFactManager()->AddInitialFacts(consumer_,
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initial_facts_);
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RepeatedPassInstances pass_instances{};
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// The following passes are likely to be very useful: many other passes
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// introduce synonyms, irrelevant ids and constants that these passes can work
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// with. We thus enable them with high probability.
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MaybeAddRepeatedPass<FuzzerPassObfuscateConstants>(90, &pass_instances);
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MaybeAddRepeatedPass<FuzzerPassApplyIdSynonyms>(90, &pass_instances);
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MaybeAddRepeatedPass<FuzzerPassReplaceIrrelevantIds>(90, &pass_instances);
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do {
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// Each call to MaybeAddRepeatedPass randomly decides whether the given pass
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// should be enabled, and adds an instance of the pass to |pass_instances|
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// if it is enabled.
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MaybeAddRepeatedPass<FuzzerPassAddAccessChains>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddBitInstructionSynonyms>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddCompositeExtract>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddCompositeInserts>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddCompositeTypes>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddCopyMemory>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddDeadBlocks>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddDeadBreaks>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddDeadContinues>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddEquationInstructions>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddFunctionCalls>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddGlobalVariables>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddImageSampleUnusedComponents>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddLoads>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddLocalVariables>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddLoopPreheaders>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddLoopsToCreateIntConstantSynonyms>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddOpPhiSynonyms>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddParameters>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddRelaxedDecorations>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddStores>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddSynonyms>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassAddVectorShuffleInstructions>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassConstructComposites>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassCopyObjects>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassDonateModules>(&pass_instances,
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donor_suppliers_);
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MaybeAddRepeatedPass<FuzzerPassDuplicateRegionsWithSelections>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassExpandVectorReductions>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassFlattenConditionalBranches>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassInlineFunctions>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassInvertComparisonOperators>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassMakeVectorOperationsDynamic>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassMergeBlocks>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassMergeFunctionReturns>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassMutatePointers>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassOutlineFunctions>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassPermuteBlocks>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassPermuteFunctionParameters>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassPermuteInstructions>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassPropagateInstructionsDown>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassPropagateInstructionsUp>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassPushIdsThroughVariables>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassReplaceAddsSubsMulsWithCarryingExtended>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassReplaceBranchesFromDeadBlocksWithExits>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassReplaceCopyMemoriesWithLoadsStores>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassReplaceCopyObjectsWithStoresLoads>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassReplaceLoadsStoresWithCopyMemories>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassReplaceParameterWithGlobal>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassReplaceLinearAlgebraInstructions>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassReplaceOpPhiIdsFromDeadPredecessors>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassReplaceOpSelectsWithConditionalBranches>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassReplaceParamsWithStruct>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassSplitBlocks>(&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassSwapBranchConditionalOperands>(
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&pass_instances);
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MaybeAddRepeatedPass<FuzzerPassWrapRegionsInSelections>(&pass_instances);
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// There is a theoretical possibility that no pass instances were created
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// until now; loop again if so.
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} while (pass_instances.GetPasses().empty());
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RepeatedPassRecommenderStandard pass_recommender(&pass_instances,
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fuzzer_context_.get());
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std::unique_ptr<RepeatedPassManager> repeated_pass_manager = nullptr;
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switch (repeated_pass_strategy_) {
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case RepeatedPassStrategy::kSimple:
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repeated_pass_manager = MakeUnique<RepeatedPassManagerSimple>(
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fuzzer_context_.get(), &pass_instances);
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break;
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case RepeatedPassStrategy::kLoopedWithRecommendations:
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repeated_pass_manager =
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MakeUnique<RepeatedPassManagerLoopedWithRecommendations>(
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fuzzer_context_.get(), &pass_instances, &pass_recommender);
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break;
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case RepeatedPassStrategy::kRandomWithRecommendations:
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repeated_pass_manager =
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MakeUnique<RepeatedPassManagerRandomWithRecommendations>(
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fuzzer_context_.get(), &pass_instances, &pass_recommender);
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break;
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}
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do {
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if (!ApplyPassAndCheckValidity(
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repeated_pass_manager->ChoosePass(transformation_sequence_out_))) {
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return {Fuzzer::FuzzerResultStatus::kFuzzerPassLedToInvalidModule,
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std::vector<uint32_t>(), protobufs::TransformationSequence()};
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}
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} while (ShouldContinueFuzzing());
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// Now apply some passes that it does not make sense to apply repeatedly,
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// as they do not unlock other passes.
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std::vector<std::unique_ptr<FuzzerPass>> final_passes;
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MaybeAddFinalPass<FuzzerPassAdjustBranchWeights>(&final_passes);
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MaybeAddFinalPass<FuzzerPassAdjustFunctionControls>(&final_passes);
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MaybeAddFinalPass<FuzzerPassAdjustLoopControls>(&final_passes);
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MaybeAddFinalPass<FuzzerPassAdjustMemoryOperandsMasks>(&final_passes);
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MaybeAddFinalPass<FuzzerPassAdjustSelectionControls>(&final_passes);
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MaybeAddFinalPass<FuzzerPassAddNoContractionDecorations>(&final_passes);
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MaybeAddFinalPass<FuzzerPassInterchangeSignednessOfIntegerOperands>(
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&final_passes);
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MaybeAddFinalPass<FuzzerPassInterchangeZeroLikeConstants>(&final_passes);
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MaybeAddFinalPass<FuzzerPassPermutePhiOperands>(&final_passes);
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MaybeAddFinalPass<FuzzerPassSwapCommutableOperands>(&final_passes);
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MaybeAddFinalPass<FuzzerPassToggleAccessChainInstruction>(&final_passes);
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for (auto& pass : final_passes) {
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if (!ApplyPassAndCheckValidity(pass.get())) {
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return {Fuzzer::FuzzerResultStatus::kFuzzerPassLedToInvalidModule,
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std::vector<uint32_t>(), protobufs::TransformationSequence()};
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}
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}
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// Encode the module as a binary.
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std::vector<uint32_t> binary_out;
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ir_context_->module()->ToBinary(&binary_out, false);
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|
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return {Fuzzer::FuzzerResultStatus::kComplete, std::move(binary_out),
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|
std::move(transformation_sequence_out_)};
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|
}
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|
|
|
bool Fuzzer::ShouldContinueFuzzing() {
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|
// There's a risk that fuzzing could get stuck, if none of the enabled fuzzer
|
|
// passes are able to apply any transformations. To guard against this we
|
|
// count the number of times some repeated pass has been applied and ensure
|
|
// that fuzzing stops if the number of repeated passes hits the limit on the
|
|
// number of transformations that can be applied.
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|
assert(
|
|
num_repeated_passes_applied_ <=
|
|
fuzzer_context_->GetTransformationLimit() &&
|
|
"The number of repeated passes applied must not exceed its upper limit.");
|
|
if (ir_context_->module()->id_bound() >= fuzzer_context_->GetIdBoundLimit()) {
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|
return false;
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|
}
|
|
if (num_repeated_passes_applied_ ==
|
|
fuzzer_context_->GetTransformationLimit()) {
|
|
// Stop because fuzzing has got stuck.
|
|
return false;
|
|
}
|
|
auto transformations_applied_so_far =
|
|
static_cast<uint32_t>(transformation_sequence_out_.transformation_size());
|
|
if (transformations_applied_so_far >=
|
|
fuzzer_context_->GetTransformationLimit()) {
|
|
// Stop because we have reached the transformation limit.
|
|
return false;
|
|
}
|
|
// If we have applied T transformations so far, and the limit on the number of
|
|
// transformations to apply is L (where T < L), the chance that we will
|
|
// continue fuzzing is:
|
|
//
|
|
// 1 - T/(2*L)
|
|
//
|
|
// That is, the chance of continuing decreases as more transformations are
|
|
// applied. Using 2*L instead of L increases the number of transformations
|
|
// that are applied on average.
|
|
auto chance_of_continuing = static_cast<uint32_t>(
|
|
100.0 * (1.0 - (static_cast<double>(transformations_applied_so_far) /
|
|
(2.0 * static_cast<double>(
|
|
fuzzer_context_->GetTransformationLimit())))));
|
|
if (!fuzzer_context_->ChoosePercentage(chance_of_continuing)) {
|
|
// We have probabilistically decided to stop.
|
|
return false;
|
|
}
|
|
// Continue fuzzing!
|
|
num_repeated_passes_applied_++;
|
|
return true;
|
|
}
|
|
|
|
} // namespace fuzz
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|
} // namespace spvtools
|