1 /* 2 * Copyright (C) 2011 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_file.h" 18 19 #include "base/stringprintf.h" 20 #include "base/unix_file/fd_file.h" 21 #include "common_compiler_test.h" 22 #include "elf_file.h" 23 #include "elf_file_impl.h" 24 #include "elf_builder.h" 25 #include "elf_writer_quick.h" 26 #include "oat.h" 27 #include "utils.h" 28 29 namespace art { 30 31 class ElfWriterTest : public CommonCompilerTest { 32 protected: 33 virtual void SetUp() { 34 ReserveImageSpace(); 35 CommonCompilerTest::SetUp(); 36 } 37 }; 38 39 #define EXPECT_ELF_FILE_ADDRESS(ef, expected_value, symbol_name, build_map) \ 40 do { \ 41 void* addr = reinterpret_cast<void*>(ef->FindSymbolAddress(SHT_DYNSYM, \ 42 symbol_name, \ 43 build_map)); \ 44 EXPECT_NE(nullptr, addr); \ 45 EXPECT_LT(static_cast<uintptr_t>(ART_BASE_ADDRESS), reinterpret_cast<uintptr_t>(addr)); \ 46 if (expected_value == nullptr) { \ 47 expected_value = addr; \ 48 } \ 49 EXPECT_EQ(expected_value, addr); \ 50 EXPECT_EQ(expected_value, ef->FindDynamicSymbolAddress(symbol_name)); \ 51 } while (false) 52 53 TEST_F(ElfWriterTest, dlsym) { 54 std::string elf_location = GetCoreOatLocation(); 55 std::string elf_filename = GetSystemImageFilename(elf_location.c_str(), kRuntimeISA); 56 LOG(INFO) << "elf_filename=" << elf_filename; 57 58 UnreserveImageSpace(); 59 void* dl_oatdata = nullptr; 60 void* dl_oatexec = nullptr; 61 void* dl_oatlastword = nullptr; 62 63 std::unique_ptr<File> file(OS::OpenFileForReading(elf_filename.c_str())); 64 ASSERT_TRUE(file.get() != nullptr); 65 { 66 std::string error_msg; 67 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(), 68 false, 69 false, 70 /*low_4gb*/false, 71 &error_msg)); 72 CHECK(ef.get() != nullptr) << error_msg; 73 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatdata, "oatdata", false); 74 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatexec, "oatexec", false); 75 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatlastword, "oatlastword", false); 76 } 77 { 78 std::string error_msg; 79 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(), 80 false, 81 false, 82 /*low_4gb*/false, 83 &error_msg)); 84 CHECK(ef.get() != nullptr) << error_msg; 85 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatdata, "oatdata", true); 86 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatexec, "oatexec", true); 87 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatlastword, "oatlastword", true); 88 } 89 { 90 std::string error_msg; 91 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(), 92 false, 93 true, 94 /*low_4gb*/false, 95 &error_msg)); 96 CHECK(ef.get() != nullptr) << error_msg; 97 CHECK(ef->Load(false, /*low_4gb*/false, &error_msg)) << error_msg; 98 EXPECT_EQ(dl_oatdata, ef->FindDynamicSymbolAddress("oatdata")); 99 EXPECT_EQ(dl_oatexec, ef->FindDynamicSymbolAddress("oatexec")); 100 EXPECT_EQ(dl_oatlastword, ef->FindDynamicSymbolAddress("oatlastword")); 101 } 102 } 103 104 TEST_F(ElfWriterTest, EncodeDecodeOatPatches) { 105 const std::vector<std::vector<uintptr_t>> test_data { 106 { 0, 4, 8, 15, 128, 200 }, 107 { 8, 8 + 127 }, 108 { 8, 8 + 128 }, 109 { }, 110 }; 111 for (const auto& patch_locations : test_data) { 112 constexpr int32_t delta = 0x11235813; 113 114 // Encode patch locations. 115 std::vector<uint8_t> oat_patches; 116 ElfBuilder<ElfTypes32>::EncodeOatPatches(ArrayRef<const uintptr_t>(patch_locations), 117 &oat_patches); 118 119 // Create buffer to be patched. 120 std::vector<uint8_t> initial_data(256); 121 for (size_t i = 0; i < initial_data.size(); i++) { 122 initial_data[i] = i; 123 } 124 125 // Patch manually. 126 std::vector<uint8_t> expected = initial_data; 127 for (uintptr_t location : patch_locations) { 128 typedef __attribute__((__aligned__(1))) uint32_t UnalignedAddress; 129 *reinterpret_cast<UnalignedAddress*>(expected.data() + location) += delta; 130 } 131 132 // Decode and apply patch locations. 133 std::vector<uint8_t> actual = initial_data; 134 ElfFileImpl32::ApplyOatPatches( 135 oat_patches.data(), oat_patches.data() + oat_patches.size(), delta, 136 actual.data(), actual.data() + actual.size()); 137 138 EXPECT_EQ(expected, actual); 139 } 140 } 141 142 } // namespace art 143
