1/*
2 * Copyright (C) 2018 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 <unistd.h>
19
20#include <android-base/file.h>
21#include <android-base/test_utils.h>
22
23#include <gtest/gtest.h>
24
25#include <unwindstack/Elf.h>
26#include <unwindstack/MapInfo.h>
27
28#include "ElfTestUtils.h"
29#include "MemoryFake.h"
30
31namespace unwindstack {
32
33class ElfCacheTest : public ::testing::Test {
34 protected:
35  static void SetUpTestCase() { memory_.reset(new MemoryFake); }
36
37  void SetUp() override { Elf::SetCachingEnabled(true); }
38
39  void TearDown() override { Elf::SetCachingEnabled(false); }
40
41  void WriteElfFile(uint64_t offset, TemporaryFile* tf, uint32_t type) {
42    ASSERT_TRUE(type == EM_ARM || type == EM_386 || type == EM_X86_64);
43    size_t ehdr_size;
44    Elf32_Ehdr ehdr32;
45    Elf64_Ehdr ehdr64;
46    void* ptr;
47    if (type == EM_ARM || type == EM_386) {
48      ehdr_size = sizeof(ehdr32);
49      ptr = &ehdr32;
50      TestInitEhdr(&ehdr32, ELFCLASS32, type);
51    } else {
52      ehdr_size = sizeof(ehdr64);
53      ptr = &ehdr64;
54      TestInitEhdr(&ehdr64, ELFCLASS64, type);
55    }
56
57    ASSERT_EQ(offset, static_cast<uint64_t>(lseek(tf->fd, offset, SEEK_SET)));
58    ASSERT_TRUE(android::base::WriteFully(tf->fd, ptr, ehdr_size));
59  }
60
61  void VerifyWithinSameMap(bool cache_enabled);
62  void VerifySameMap(bool cache_enabled);
63  void VerifyWithinSameMapNeverReadAtZero(bool cache_enabled);
64
65  static std::shared_ptr<Memory> memory_;
66};
67
68std::shared_ptr<Memory> ElfCacheTest::memory_;
69
70void ElfCacheTest::VerifySameMap(bool cache_enabled) {
71  if (!cache_enabled) {
72    Elf::SetCachingEnabled(false);
73  }
74
75  TemporaryFile tf;
76  ASSERT_TRUE(tf.fd != -1);
77  WriteElfFile(0, &tf, EM_ARM);
78  close(tf.fd);
79
80  uint64_t start = 0x1000;
81  uint64_t end = 0x20000;
82  MapInfo info1(start, end, 0, 0x5, tf.path);
83  MapInfo info2(start, end, 0, 0x5, tf.path);
84
85  Elf* elf1 = info1.GetElf(memory_, true);
86  ASSERT_TRUE(elf1->valid());
87  Elf* elf2 = info2.GetElf(memory_, true);
88  ASSERT_TRUE(elf2->valid());
89
90  if (cache_enabled) {
91    EXPECT_EQ(elf1, elf2);
92  } else {
93    EXPECT_NE(elf1, elf2);
94  }
95}
96
97TEST_F(ElfCacheTest, no_caching) {
98  VerifySameMap(false);
99}
100
101TEST_F(ElfCacheTest, caching_invalid_elf) {
102  VerifySameMap(true);
103}
104
105void ElfCacheTest::VerifyWithinSameMap(bool cache_enabled) {
106  if (!cache_enabled) {
107    Elf::SetCachingEnabled(false);
108  }
109
110  TemporaryFile tf;
111  ASSERT_TRUE(tf.fd != -1);
112  WriteElfFile(0, &tf, EM_ARM);
113  WriteElfFile(0x100, &tf, EM_386);
114  WriteElfFile(0x200, &tf, EM_X86_64);
115  lseek(tf.fd, 0x500, SEEK_SET);
116  uint8_t value = 0;
117  write(tf.fd, &value, 1);
118  close(tf.fd);
119
120  uint64_t start = 0x1000;
121  uint64_t end = 0x20000;
122  // Will have an elf at offset 0 in file.
123  MapInfo info0_1(start, end, 0, 0x5, tf.path);
124  MapInfo info0_2(start, end, 0, 0x5, tf.path);
125  // Will have an elf at offset 0x100 in file.
126  MapInfo info100_1(start, end, 0x100, 0x5, tf.path);
127  MapInfo info100_2(start, end, 0x100, 0x5, tf.path);
128  // Will have an elf at offset 0x200 in file.
129  MapInfo info200_1(start, end, 0x200, 0x5, tf.path);
130  MapInfo info200_2(start, end, 0x200, 0x5, tf.path);
131  // Will have an elf at offset 0 in file.
132  MapInfo info300_1(start, end, 0x300, 0x5, tf.path);
133  MapInfo info300_2(start, end, 0x300, 0x5, tf.path);
134
135  Elf* elf0_1 = info0_1.GetElf(memory_, true);
136  ASSERT_TRUE(elf0_1->valid());
137  EXPECT_EQ(ARCH_ARM, elf0_1->arch());
138  Elf* elf0_2 = info0_2.GetElf(memory_, true);
139  ASSERT_TRUE(elf0_2->valid());
140  EXPECT_EQ(ARCH_ARM, elf0_2->arch());
141  EXPECT_EQ(0U, info0_1.elf_offset);
142  EXPECT_EQ(0U, info0_2.elf_offset);
143  if (cache_enabled) {
144    EXPECT_EQ(elf0_1, elf0_2);
145  } else {
146    EXPECT_NE(elf0_1, elf0_2);
147  }
148
149  Elf* elf100_1 = info100_1.GetElf(memory_, true);
150  ASSERT_TRUE(elf100_1->valid());
151  EXPECT_EQ(ARCH_X86, elf100_1->arch());
152  Elf* elf100_2 = info100_2.GetElf(memory_, true);
153  ASSERT_TRUE(elf100_2->valid());
154  EXPECT_EQ(ARCH_X86, elf100_2->arch());
155  EXPECT_EQ(0U, info100_1.elf_offset);
156  EXPECT_EQ(0U, info100_2.elf_offset);
157  if (cache_enabled) {
158    EXPECT_EQ(elf100_1, elf100_2);
159  } else {
160    EXPECT_NE(elf100_1, elf100_2);
161  }
162
163  Elf* elf200_1 = info200_1.GetElf(memory_, true);
164  ASSERT_TRUE(elf200_1->valid());
165  EXPECT_EQ(ARCH_X86_64, elf200_1->arch());
166  Elf* elf200_2 = info200_2.GetElf(memory_, true);
167  ASSERT_TRUE(elf200_2->valid());
168  EXPECT_EQ(ARCH_X86_64, elf200_2->arch());
169  EXPECT_EQ(0U, info200_1.elf_offset);
170  EXPECT_EQ(0U, info200_2.elf_offset);
171  if (cache_enabled) {
172    EXPECT_EQ(elf200_1, elf200_2);
173  } else {
174    EXPECT_NE(elf200_1, elf200_2);
175  }
176
177  Elf* elf300_1 = info300_1.GetElf(memory_, true);
178  ASSERT_TRUE(elf300_1->valid());
179  EXPECT_EQ(ARCH_ARM, elf300_1->arch());
180  Elf* elf300_2 = info300_2.GetElf(memory_, true);
181  ASSERT_TRUE(elf300_2->valid());
182  EXPECT_EQ(ARCH_ARM, elf300_2->arch());
183  EXPECT_EQ(0x300U, info300_1.elf_offset);
184  EXPECT_EQ(0x300U, info300_2.elf_offset);
185  if (cache_enabled) {
186    EXPECT_EQ(elf300_1, elf300_2);
187    EXPECT_EQ(elf0_1, elf300_1);
188  } else {
189    EXPECT_NE(elf300_1, elf300_2);
190    EXPECT_NE(elf0_1, elf300_1);
191  }
192}
193
194TEST_F(ElfCacheTest, no_caching_valid_elf_offset_non_zero) {
195  VerifyWithinSameMap(false);
196}
197
198TEST_F(ElfCacheTest, caching_valid_elf_offset_non_zero) {
199  VerifyWithinSameMap(true);
200}
201
202// Verify that when reading from multiple non-zero offsets in the same map
203// that when cached, all of the elf objects are the same.
204void ElfCacheTest::VerifyWithinSameMapNeverReadAtZero(bool cache_enabled) {
205  if (!cache_enabled) {
206    Elf::SetCachingEnabled(false);
207  }
208
209  TemporaryFile tf;
210  ASSERT_TRUE(tf.fd != -1);
211  WriteElfFile(0, &tf, EM_ARM);
212  lseek(tf.fd, 0x500, SEEK_SET);
213  uint8_t value = 0;
214  write(tf.fd, &value, 1);
215  close(tf.fd);
216
217  uint64_t start = 0x1000;
218  uint64_t end = 0x20000;
219  // Multiple info sections at different offsets will have non-zero elf offsets.
220  MapInfo info300_1(start, end, 0x300, 0x5, tf.path);
221  MapInfo info300_2(start, end, 0x300, 0x5, tf.path);
222  MapInfo info400_1(start, end, 0x400, 0x5, tf.path);
223  MapInfo info400_2(start, end, 0x400, 0x5, tf.path);
224
225  Elf* elf300_1 = info300_1.GetElf(memory_, true);
226  ASSERT_TRUE(elf300_1->valid());
227  EXPECT_EQ(ARCH_ARM, elf300_1->arch());
228  Elf* elf300_2 = info300_2.GetElf(memory_, true);
229  ASSERT_TRUE(elf300_2->valid());
230  EXPECT_EQ(ARCH_ARM, elf300_2->arch());
231  EXPECT_EQ(0x300U, info300_1.elf_offset);
232  EXPECT_EQ(0x300U, info300_2.elf_offset);
233  if (cache_enabled) {
234    EXPECT_EQ(elf300_1, elf300_2);
235  } else {
236    EXPECT_NE(elf300_1, elf300_2);
237  }
238
239  Elf* elf400_1 = info400_1.GetElf(memory_, true);
240  ASSERT_TRUE(elf400_1->valid());
241  EXPECT_EQ(ARCH_ARM, elf400_1->arch());
242  Elf* elf400_2 = info400_2.GetElf(memory_, true);
243  ASSERT_TRUE(elf400_2->valid());
244  EXPECT_EQ(ARCH_ARM, elf400_2->arch());
245  EXPECT_EQ(0x400U, info400_1.elf_offset);
246  EXPECT_EQ(0x400U, info400_2.elf_offset);
247  if (cache_enabled) {
248    EXPECT_EQ(elf400_1, elf400_2);
249    EXPECT_EQ(elf300_1, elf400_1);
250  } else {
251    EXPECT_NE(elf400_1, elf400_2);
252    EXPECT_NE(elf300_1, elf400_1);
253  }
254}
255
256TEST_F(ElfCacheTest, no_caching_valid_elf_offset_non_zero_never_read_at_zero) {
257  VerifyWithinSameMapNeverReadAtZero(false);
258}
259
260TEST_F(ElfCacheTest, caching_valid_elf_offset_non_zero_never_read_at_zero) {
261  VerifyWithinSameMapNeverReadAtZero(true);
262}
263
264}  // namespace unwindstack
265