1 /* 2 * Copyright (C) 2016 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <elf.h> 18 #include <errno.h> 19 #include <signal.h> 20 #include <string.h> 21 #include <sys/mman.h> 22 #include <sys/ptrace.h> 23 #include <sys/types.h> 24 #include <unistd.h> 25 26 #include <atomic> 27 #include <memory> 28 #include <thread> 29 #include <vector> 30 31 #include <android-base/file.h> 32 #include <android-base/test_utils.h> 33 #include <gtest/gtest.h> 34 35 #include <unwindstack/Elf.h> 36 #include <unwindstack/MapInfo.h> 37 #include <unwindstack/Maps.h> 38 #include <unwindstack/Memory.h> 39 40 #include "ElfFake.h" 41 #include "ElfTestUtils.h" 42 #include "MemoryFake.h" 43 44 namespace unwindstack { 45 46 class MapInfoGetLoadBiasTest : public ::testing::Test { 47 protected: 48 void SetUp() override { 49 memory_ = new MemoryFake; 50 process_memory_.reset(memory_); 51 elf_ = new ElfFake(new MemoryFake); 52 elf_container_.reset(elf_); 53 map_info_.reset(new MapInfo(0x1000, 0x20000, 0, PROT_READ | PROT_WRITE, "")); 54 } 55 56 void MultipleThreadTest(uint64_t expected_load_bias); 57 58 std::shared_ptr<Memory> process_memory_; 59 MemoryFake* memory_; 60 ElfFake* elf_; 61 std::unique_ptr<ElfFake> elf_container_; 62 std::unique_ptr<MapInfo> map_info_; 63 }; 64 65 TEST_F(MapInfoGetLoadBiasTest, no_elf_and_no_valid_elf_in_memory) { 66 MapInfo info(0x1000, 0x2000, 0, PROT_READ, ""); 67 68 EXPECT_EQ(0U, info.GetLoadBias(process_memory_)); 69 } 70 71 TEST_F(MapInfoGetLoadBiasTest, load_bias_cached_from_elf) { 72 map_info_->elf.reset(elf_container_.release()); 73 74 elf_->FakeSetLoadBias(0); 75 EXPECT_EQ(0U, map_info_->GetLoadBias(process_memory_)); 76 77 elf_->FakeSetLoadBias(0x1000); 78 EXPECT_EQ(0U, map_info_->GetLoadBias(process_memory_)); 79 } 80 81 TEST_F(MapInfoGetLoadBiasTest, elf_exists) { 82 map_info_->elf.reset(elf_container_.release()); 83 84 elf_->FakeSetLoadBias(0); 85 EXPECT_EQ(0U, map_info_->GetLoadBias(process_memory_)); 86 87 map_info_->load_bias = static_cast<uint64_t>(-1); 88 elf_->FakeSetLoadBias(0x1000); 89 EXPECT_EQ(0x1000U, map_info_->GetLoadBias(process_memory_)); 90 } 91 92 void MapInfoGetLoadBiasTest::MultipleThreadTest(uint64_t expected_load_bias) { 93 static constexpr size_t kNumConcurrentThreads = 100; 94 95 uint64_t load_bias_values[kNumConcurrentThreads]; 96 std::vector<std::thread*> threads; 97 98 std::atomic_bool wait; 99 wait = true; 100 // Create all of the threads and have them do the GetLoadBias at the same time 101 // to make it likely that a race will occur. 102 for (size_t i = 0; i < kNumConcurrentThreads; i++) { 103 std::thread* thread = new std::thread([i, this, &wait, &load_bias_values]() { 104 while (wait) 105 ; 106 load_bias_values[i] = map_info_->GetLoadBias(process_memory_); 107 }); 108 threads.push_back(thread); 109 } 110 111 // Set them all going and wait for the threads to finish. 112 wait = false; 113 for (auto thread : threads) { 114 thread->join(); 115 delete thread; 116 } 117 118 // Now verify that all of the elf files are exactly the same and valid. 119 for (size_t i = 0; i < kNumConcurrentThreads; i++) { 120 EXPECT_EQ(expected_load_bias, load_bias_values[i]) << "Thread " << i << " mismatched."; 121 } 122 } 123 124 TEST_F(MapInfoGetLoadBiasTest, multiple_thread_elf_exists) { 125 map_info_->elf.reset(elf_container_.release()); 126 elf_->FakeSetLoadBias(0x1000); 127 128 MultipleThreadTest(0x1000); 129 } 130 131 static void InitElfData(MemoryFake* memory, uint64_t offset) { 132 Elf32_Ehdr ehdr; 133 TestInitEhdr(&ehdr, ELFCLASS32, EM_ARM); 134 ehdr.e_phoff = 0x5000; 135 ehdr.e_phnum = 2; 136 ehdr.e_phentsize = sizeof(Elf32_Phdr); 137 memory->SetMemory(offset, &ehdr, sizeof(ehdr)); 138 139 Elf32_Phdr phdr; 140 memset(&phdr, 0, sizeof(phdr)); 141 phdr.p_type = PT_NULL; 142 memory->SetMemory(offset + 0x5000, &phdr, sizeof(phdr)); 143 phdr.p_type = PT_LOAD; 144 phdr.p_offset = 0; 145 phdr.p_vaddr = 0xe000; 146 memory->SetMemory(offset + 0x5000 + sizeof(phdr), &phdr, sizeof(phdr)); 147 } 148 149 TEST_F(MapInfoGetLoadBiasTest, elf_exists_in_memory) { 150 InitElfData(memory_, map_info_->start); 151 152 EXPECT_EQ(0xe000U, map_info_->GetLoadBias(process_memory_)); 153 } 154 155 TEST_F(MapInfoGetLoadBiasTest, elf_exists_in_memory_cached) { 156 InitElfData(memory_, map_info_->start); 157 158 EXPECT_EQ(0xe000U, map_info_->GetLoadBias(process_memory_)); 159 160 memory_->Clear(); 161 EXPECT_EQ(0xe000U, map_info_->GetLoadBias(process_memory_)); 162 } 163 164 TEST_F(MapInfoGetLoadBiasTest, multiple_thread_elf_exists_in_memory) { 165 InitElfData(memory_, map_info_->start); 166 167 MultipleThreadTest(0xe000); 168 } 169 170 } // namespace unwindstack 171
