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 
19 #include <gtest/gtest.h>
20 
21 #include <vector>
22 
23 #include <unwindstack/MachineArm.h>
24 #include <unwindstack/RegsArm.h>
25 
26 #include "ElfInterfaceArm.h"
27 
28 #include "ElfFake.h"
29 #include "MemoryFake.h"
30 
31 namespace unwindstack {
32 
33 class ElfInterfaceArmTest : public ::testing::Test {
34  protected:
SetUp()35   void SetUp() override {
36     memory_.Clear();
37     process_memory_.Clear();
38   }
39 
40   MemoryFake memory_;
41   MemoryFake process_memory_;
42 };
43 
TEST_F(ElfInterfaceArmTest,GetPrel32Addr)44 TEST_F(ElfInterfaceArmTest, GetPrel32Addr) {
45   ElfInterfaceArmFake interface(&memory_);
46   memory_.SetData32(0x1000, 0x230000);
47 
48   uint32_t value;
49   ASSERT_TRUE(interface.GetPrel31Addr(0x1000, &value));
50   ASSERT_EQ(0x231000U, value);
51 
52   memory_.SetData32(0x1000, 0x80001000);
53   ASSERT_TRUE(interface.GetPrel31Addr(0x1000, &value));
54   ASSERT_EQ(0x2000U, value);
55 
56   memory_.SetData32(0x1000, 0x70001000);
57   ASSERT_TRUE(interface.GetPrel31Addr(0x1000, &value));
58   ASSERT_EQ(0xf0002000U, value);
59 }
60 
TEST_F(ElfInterfaceArmTest,FindEntry_start_zero)61 TEST_F(ElfInterfaceArmTest, FindEntry_start_zero) {
62   ElfInterfaceArmFake interface(&memory_);
63   interface.FakeSetStartOffset(0);
64   interface.FakeSetTotalEntries(10);
65 
66   uint64_t entry_offset;
67   ASSERT_FALSE(interface.FindEntry(0x1000, &entry_offset));
68 }
69 
TEST_F(ElfInterfaceArmTest,FindEntry_no_entries)70 TEST_F(ElfInterfaceArmTest, FindEntry_no_entries) {
71   ElfInterfaceArmFake interface(&memory_);
72   interface.FakeSetStartOffset(0x100);
73   interface.FakeSetTotalEntries(0);
74 
75   uint64_t entry_offset;
76   ASSERT_FALSE(interface.FindEntry(0x1000, &entry_offset));
77 }
78 
TEST_F(ElfInterfaceArmTest,FindEntry_no_valid_memory)79 TEST_F(ElfInterfaceArmTest, FindEntry_no_valid_memory) {
80   ElfInterfaceArmFake interface(&memory_);
81   interface.FakeSetStartOffset(0x100);
82   interface.FakeSetTotalEntries(2);
83 
84   uint64_t entry_offset;
85   ASSERT_FALSE(interface.FindEntry(0x1000, &entry_offset));
86 }
87 
TEST_F(ElfInterfaceArmTest,FindEntry_ip_before_first)88 TEST_F(ElfInterfaceArmTest, FindEntry_ip_before_first) {
89   ElfInterfaceArmFake interface(&memory_);
90   interface.FakeSetStartOffset(0x1000);
91   interface.FakeSetTotalEntries(1);
92   memory_.SetData32(0x1000, 0x6000);
93 
94   uint64_t entry_offset;
95   ASSERT_FALSE(interface.FindEntry(0x1000, &entry_offset));
96 }
97 
TEST_F(ElfInterfaceArmTest,FindEntry_single_entry_negative_value)98 TEST_F(ElfInterfaceArmTest, FindEntry_single_entry_negative_value) {
99   ElfInterfaceArmFake interface(&memory_);
100   interface.FakeSetStartOffset(0x8000);
101   interface.FakeSetTotalEntries(1);
102   memory_.SetData32(0x8000, 0x7fffff00);
103 
104   uint64_t entry_offset;
105   ASSERT_TRUE(interface.FindEntry(0x7ff0, &entry_offset));
106   ASSERT_EQ(0x8000U, entry_offset);
107 }
108 
TEST_F(ElfInterfaceArmTest,FindEntry_two_entries)109 TEST_F(ElfInterfaceArmTest, FindEntry_two_entries) {
110   ElfInterfaceArmFake interface(&memory_);
111   interface.FakeSetStartOffset(0x1000);
112   interface.FakeSetTotalEntries(2);
113   memory_.SetData32(0x1000, 0x6000);
114   memory_.SetData32(0x1008, 0x7000);
115 
116   uint64_t entry_offset;
117   ASSERT_TRUE(interface.FindEntry(0x7000, &entry_offset));
118   ASSERT_EQ(0x1000U, entry_offset);
119 }
120 
TEST_F(ElfInterfaceArmTest,FindEntry_last_check_single_entry)121 TEST_F(ElfInterfaceArmTest, FindEntry_last_check_single_entry) {
122   ElfInterfaceArmFake interface(&memory_);
123   interface.FakeSetStartOffset(0x1000);
124   interface.FakeSetTotalEntries(1);
125   memory_.SetData32(0x1000, 0x6000);
126 
127   uint64_t entry_offset;
128   ASSERT_TRUE(interface.FindEntry(0x7000, &entry_offset));
129   ASSERT_EQ(0x1000U, entry_offset);
130 
131   // To guarantee that we are using the cache on the second run,
132   // set the memory to a different value.
133   memory_.SetData32(0x1000, 0x8000);
134   ASSERT_TRUE(interface.FindEntry(0x7004, &entry_offset));
135   ASSERT_EQ(0x1000U, entry_offset);
136 }
137 
TEST_F(ElfInterfaceArmTest,FindEntry_last_check_multiple_entries)138 TEST_F(ElfInterfaceArmTest, FindEntry_last_check_multiple_entries) {
139   ElfInterfaceArmFake interface(&memory_);
140   interface.FakeSetStartOffset(0x1000);
141   interface.FakeSetTotalEntries(2);
142   memory_.SetData32(0x1000, 0x6000);
143   memory_.SetData32(0x1008, 0x8000);
144 
145   uint64_t entry_offset;
146   ASSERT_TRUE(interface.FindEntry(0x9008, &entry_offset));
147   ASSERT_EQ(0x1008U, entry_offset);
148 
149   // To guarantee that we are using the cache on the second run,
150   // set the memory to a different value.
151   memory_.SetData32(0x1000, 0x16000);
152   memory_.SetData32(0x1008, 0x18000);
153   ASSERT_TRUE(interface.FindEntry(0x9100, &entry_offset));
154   ASSERT_EQ(0x1008U, entry_offset);
155 }
156 
TEST_F(ElfInterfaceArmTest,FindEntry_multiple_entries_even)157 TEST_F(ElfInterfaceArmTest, FindEntry_multiple_entries_even) {
158   ElfInterfaceArmFake interface(&memory_);
159   interface.FakeSetStartOffset(0x1000);
160   interface.FakeSetTotalEntries(4);
161   memory_.SetData32(0x1000, 0x6000);
162   memory_.SetData32(0x1008, 0x7000);
163   memory_.SetData32(0x1010, 0x8000);
164   memory_.SetData32(0x1018, 0x9000);
165 
166   uint64_t entry_offset;
167   ASSERT_TRUE(interface.FindEntry(0x9100, &entry_offset));
168   ASSERT_EQ(0x1010U, entry_offset);
169 
170   // To guarantee that we are using the cache on the second run,
171   // set the memory to a different value.
172   memory_.SetData32(0x1000, 0x16000);
173   memory_.SetData32(0x1008, 0x17000);
174   memory_.SetData32(0x1010, 0x18000);
175   memory_.SetData32(0x1018, 0x19000);
176   ASSERT_TRUE(interface.FindEntry(0x9100, &entry_offset));
177   ASSERT_EQ(0x1010U, entry_offset);
178 }
179 
TEST_F(ElfInterfaceArmTest,FindEntry_multiple_entries_odd)180 TEST_F(ElfInterfaceArmTest, FindEntry_multiple_entries_odd) {
181   ElfInterfaceArmFake interface(&memory_);
182   interface.FakeSetStartOffset(0x1000);
183   interface.FakeSetTotalEntries(5);
184   memory_.SetData32(0x1000, 0x5000);
185   memory_.SetData32(0x1008, 0x6000);
186   memory_.SetData32(0x1010, 0x7000);
187   memory_.SetData32(0x1018, 0x8000);
188   memory_.SetData32(0x1020, 0x9000);
189 
190   uint64_t entry_offset;
191   ASSERT_TRUE(interface.FindEntry(0x8100, &entry_offset));
192   ASSERT_EQ(0x1010U, entry_offset);
193 
194   // To guarantee that we are using the cache on the second run,
195   // set the memory to a different value.
196   memory_.SetData32(0x1000, 0x15000);
197   memory_.SetData32(0x1008, 0x16000);
198   memory_.SetData32(0x1010, 0x17000);
199   memory_.SetData32(0x1018, 0x18000);
200   memory_.SetData32(0x1020, 0x19000);
201   ASSERT_TRUE(interface.FindEntry(0x8100, &entry_offset));
202   ASSERT_EQ(0x1010U, entry_offset);
203 }
204 
TEST_F(ElfInterfaceArmTest,iterate)205 TEST_F(ElfInterfaceArmTest, iterate) {
206   ElfInterfaceArmFake interface(&memory_);
207   interface.FakeSetStartOffset(0x1000);
208   interface.FakeSetTotalEntries(5);
209   memory_.SetData32(0x1000, 0x5000);
210   memory_.SetData32(0x1008, 0x6000);
211   memory_.SetData32(0x1010, 0x7000);
212   memory_.SetData32(0x1018, 0x8000);
213   memory_.SetData32(0x1020, 0x9000);
214 
215   std::vector<uint32_t> entries;
216   for (auto addr : interface) {
217     entries.push_back(addr);
218   }
219   ASSERT_EQ(5U, entries.size());
220   ASSERT_EQ(0x6000U, entries[0]);
221   ASSERT_EQ(0x7008U, entries[1]);
222   ASSERT_EQ(0x8010U, entries[2]);
223   ASSERT_EQ(0x9018U, entries[3]);
224   ASSERT_EQ(0xa020U, entries[4]);
225 
226   // Make sure the iterate cached the entries.
227   memory_.SetData32(0x1000, 0x11000);
228   memory_.SetData32(0x1008, 0x12000);
229   memory_.SetData32(0x1010, 0x13000);
230   memory_.SetData32(0x1018, 0x14000);
231   memory_.SetData32(0x1020, 0x15000);
232 
233   entries.clear();
234   for (auto addr : interface) {
235     entries.push_back(addr);
236   }
237   ASSERT_EQ(5U, entries.size());
238   ASSERT_EQ(0x6000U, entries[0]);
239   ASSERT_EQ(0x7008U, entries[1]);
240   ASSERT_EQ(0x8010U, entries[2]);
241   ASSERT_EQ(0x9018U, entries[3]);
242   ASSERT_EQ(0xa020U, entries[4]);
243 }
244 
TEST_F(ElfInterfaceArmTest,HandleUnknownType_arm_exidx)245 TEST_F(ElfInterfaceArmTest, HandleUnknownType_arm_exidx) {
246   ElfInterfaceArmFake interface(&memory_);
247 
248   interface.FakeSetStartOffset(0x1000);
249   interface.FakeSetTotalEntries(100);
250 
251   // Verify that if the type is not the one we want, we don't set the values.
252   interface.HandleUnknownType(0x70000000, 0x2000, 320);
253   ASSERT_EQ(0x1000U, interface.start_offset());
254   ASSERT_EQ(100U, interface.total_entries());
255 
256   // Everything is correct and present.
257   interface.HandleUnknownType(0x70000001, 0x2000, 320);
258   ASSERT_EQ(0x2000U, interface.start_offset());
259   ASSERT_EQ(40U, interface.total_entries());
260 }
261 
TEST_F(ElfInterfaceArmTest,StepExidx)262 TEST_F(ElfInterfaceArmTest, StepExidx) {
263   ElfInterfaceArmFake interface(&memory_);
264 
265   // FindEntry fails.
266   bool finished;
267   ASSERT_FALSE(interface.StepExidx(0x7000, nullptr, nullptr, &finished));
268   EXPECT_EQ(ERROR_UNWIND_INFO, interface.LastErrorCode());
269 
270   // ExtractEntry should fail.
271   interface.FakeSetStartOffset(0x1000);
272   interface.FakeSetTotalEntries(2);
273   memory_.SetData32(0x1000, 0x6000);
274   memory_.SetData32(0x1008, 0x8000);
275 
276   RegsArm regs;
277   regs[ARM_REG_SP] = 0x1000;
278   regs[ARM_REG_LR] = 0x20000;
279   regs.set_sp(regs[ARM_REG_SP]);
280   regs.set_pc(0x1234);
281   ASSERT_FALSE(interface.StepExidx(0x7000, &regs, &process_memory_, &finished));
282   EXPECT_EQ(ERROR_MEMORY_INVALID, interface.LastErrorCode());
283   EXPECT_EQ(0x1004U, interface.LastErrorAddress());
284 
285   // Eval should fail.
286   memory_.SetData32(0x1004, 0x81000000);
287   ASSERT_FALSE(interface.StepExidx(0x7000, &regs, &process_memory_, &finished));
288   EXPECT_EQ(ERROR_UNWIND_INFO, interface.LastErrorCode());
289 
290   // Everything should pass.
291   memory_.SetData32(0x1004, 0x80b0b0b0);
292   ASSERT_TRUE(interface.StepExidx(0x7000, &regs, &process_memory_, &finished));
293   EXPECT_EQ(ERROR_UNWIND_INFO, interface.LastErrorCode());
294   ASSERT_FALSE(finished);
295   ASSERT_EQ(0x1000U, regs.sp());
296   ASSERT_EQ(0x1000U, regs[ARM_REG_SP]);
297   ASSERT_EQ(0x20000U, regs.pc());
298   ASSERT_EQ(0x20000U, regs[ARM_REG_PC]);
299 
300   // Load bias is non-zero.
301   interface.set_load_bias(0x1000);
302   ASSERT_TRUE(interface.StepExidx(0x8000, &regs, &process_memory_, &finished));
303   EXPECT_EQ(ERROR_UNWIND_INFO, interface.LastErrorCode());
304 
305   // Pc too small.
306   interface.set_load_bias(0x9000);
307   ASSERT_FALSE(interface.StepExidx(0x8000, &regs, &process_memory_, &finished));
308   EXPECT_EQ(ERROR_UNWIND_INFO, interface.LastErrorCode());
309 }
310 
TEST_F(ElfInterfaceArmTest,StepExidx_pc_set)311 TEST_F(ElfInterfaceArmTest, StepExidx_pc_set) {
312   ElfInterfaceArmFake interface(&memory_);
313 
314   interface.FakeSetStartOffset(0x1000);
315   interface.FakeSetTotalEntries(2);
316   memory_.SetData32(0x1000, 0x6000);
317   memory_.SetData32(0x1004, 0x808800b0);
318   memory_.SetData32(0x1008, 0x8000);
319   process_memory_.SetData32(0x10000, 0x10);
320 
321   RegsArm regs;
322   regs[ARM_REG_SP] = 0x10000;
323   regs[ARM_REG_LR] = 0x20000;
324   regs.set_sp(regs[ARM_REG_SP]);
325   regs.set_pc(0x1234);
326 
327   // Everything should pass.
328   bool finished;
329   ASSERT_TRUE(interface.StepExidx(0x7000, &regs, &process_memory_, &finished));
330   EXPECT_EQ(ERROR_NONE, interface.LastErrorCode());
331   ASSERT_FALSE(finished);
332   ASSERT_EQ(0x10004U, regs.sp());
333   ASSERT_EQ(0x10004U, regs[ARM_REG_SP]);
334   ASSERT_EQ(0x10U, regs.pc());
335   ASSERT_EQ(0x10U, regs[ARM_REG_PC]);
336 }
337 
TEST_F(ElfInterfaceArmTest,StepExidx_cant_unwind)338 TEST_F(ElfInterfaceArmTest, StepExidx_cant_unwind) {
339   ElfInterfaceArmFake interface(&memory_);
340 
341   interface.FakeSetStartOffset(0x1000);
342   interface.FakeSetTotalEntries(1);
343   memory_.SetData32(0x1000, 0x6000);
344   memory_.SetData32(0x1004, 1);
345 
346   RegsArm regs;
347   regs[ARM_REG_SP] = 0x10000;
348   regs[ARM_REG_LR] = 0x20000;
349   regs.set_sp(regs[ARM_REG_SP]);
350   regs.set_pc(0x1234);
351 
352   bool finished;
353   ASSERT_TRUE(interface.StepExidx(0x7000, &regs, &process_memory_, &finished));
354   EXPECT_EQ(ERROR_NONE, interface.LastErrorCode());
355   ASSERT_TRUE(finished);
356   ASSERT_EQ(0x10000U, regs.sp());
357   ASSERT_EQ(0x10000U, regs[ARM_REG_SP]);
358   ASSERT_EQ(0x1234U, regs.pc());
359 }
360 
TEST_F(ElfInterfaceArmTest,StepExidx_refuse_unwind)361 TEST_F(ElfInterfaceArmTest, StepExidx_refuse_unwind) {
362   ElfInterfaceArmFake interface(&memory_);
363 
364   interface.FakeSetStartOffset(0x1000);
365   interface.FakeSetTotalEntries(1);
366   memory_.SetData32(0x1000, 0x6000);
367   memory_.SetData32(0x1004, 0x808000b0);
368 
369   RegsArm regs;
370   regs[ARM_REG_SP] = 0x10000;
371   regs[ARM_REG_LR] = 0x20000;
372   regs.set_sp(regs[ARM_REG_SP]);
373   regs.set_pc(0x1234);
374 
375   bool finished;
376   ASSERT_TRUE(interface.StepExidx(0x7000, &regs, &process_memory_, &finished));
377   EXPECT_EQ(ERROR_NONE, interface.LastErrorCode());
378   ASSERT_TRUE(finished);
379   ASSERT_EQ(0x10000U, regs.sp());
380   ASSERT_EQ(0x10000U, regs[ARM_REG_SP]);
381   ASSERT_EQ(0x1234U, regs.pc());
382 }
383 
TEST_F(ElfInterfaceArmTest,StepExidx_pc_zero)384 TEST_F(ElfInterfaceArmTest, StepExidx_pc_zero) {
385   ElfInterfaceArmFake interface(&memory_);
386 
387   interface.FakeSetStartOffset(0x1000);
388   interface.FakeSetTotalEntries(1);
389   memory_.SetData32(0x1000, 0x6000);
390   // Set the pc using a pop r15 command.
391   memory_.SetData32(0x1004, 0x808800b0);
392 
393   // pc value of zero.
394   process_memory_.SetData32(0x10000, 0);
395 
396   RegsArm regs;
397   regs[ARM_REG_SP] = 0x10000;
398   regs[ARM_REG_LR] = 0x20000;
399   regs.set_sp(regs[ARM_REG_SP]);
400   regs.set_pc(0x1234);
401 
402   bool finished;
403   ASSERT_TRUE(interface.StepExidx(0x7000, &regs, &process_memory_, &finished));
404   EXPECT_EQ(ERROR_NONE, interface.LastErrorCode());
405   ASSERT_TRUE(finished);
406   ASSERT_EQ(0U, regs.pc());
407 
408   // Now set the pc from the lr register (pop r14).
409   memory_.SetData32(0x1004, 0x808400b0);
410 
411   regs[ARM_REG_SP] = 0x10000;
412   regs[ARM_REG_LR] = 0x20000;
413   regs.set_sp(regs[ARM_REG_SP]);
414   regs.set_pc(0x1234);
415 
416   ASSERT_TRUE(interface.StepExidx(0x7000, &regs, &process_memory_, &finished));
417   EXPECT_EQ(ERROR_NONE, interface.LastErrorCode());
418   ASSERT_TRUE(finished);
419   ASSERT_EQ(0U, regs.pc());
420 }
421 
422 }  // namespace unwindstack
423