platform_system_core/libunwindstack/tests/ElfTest.cpp
Christopher Ferris be788d891d Allow multiple threads sharing a map to unwind.
Add a mutex in MapInfo, and a mutex in Elf. Lock the creation of an Elf
file using the MapInfo mutex, and lock when calling Step, GetFunctionName,
or GetSoname since they can modify information in the object. It might
be beneficial to use a fine grained lock in the future.

Change the Maps object to contain a vector of MapInfo pointers rather
than the total objects. This avoids copying this data around.

Add a test to libbacktrace to verify that sharing a map while doing
unwinds in different threads works.

Add concurrency tests in libunwindstack to verify the locking works.

Add always inline to the RegsGetLocal arm and aarch64 functions. I had
a case where clang did not inline the code, so make sure this is specified.

Bug: 68813077

Test: New unit tests to cover the case. Passes all unit tests.
Test: Ran a monkey test while dumping bugreports and verified that
Test: no crashes in libunwind.
Test: Remove the locking and verified that all of the concurrenty tests fail.
Change-Id: I769e728c676f6bdae9e64ce4cdc03b6749beae03
2017-11-28 15:20:38 -08:00

366 lines
10 KiB
C++

/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <elf.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <gmock/gmock.h>
#include <gtest/gtest.h>
#include <unwindstack/Elf.h>
#include <unwindstack/MapInfo.h>
#include "ElfFake.h"
#include "ElfTestUtils.h"
#include "LogFake.h"
#include "MemoryFake.h"
#if !defined(PT_ARM_EXIDX)
#define PT_ARM_EXIDX 0x70000001
#endif
namespace unwindstack {
class ElfTest : public ::testing::Test {
protected:
void SetUp() override {
memory_ = new MemoryFake;
}
void InitElf32(uint32_t machine_type) {
Elf32_Ehdr ehdr;
TestInitEhdr<Elf32_Ehdr>(&ehdr, ELFCLASS32, machine_type);
ehdr.e_phoff = 0x100;
ehdr.e_ehsize = sizeof(ehdr);
ehdr.e_phentsize = sizeof(Elf32_Phdr);
ehdr.e_phnum = 1;
ehdr.e_shentsize = sizeof(Elf32_Shdr);
if (machine_type == EM_ARM) {
ehdr.e_flags = 0x5000200;
ehdr.e_phnum = 2;
}
memory_->SetMemory(0, &ehdr, sizeof(ehdr));
Elf32_Phdr phdr;
memset(&phdr, 0, sizeof(phdr));
phdr.p_type = PT_LOAD;
phdr.p_filesz = 0x10000;
phdr.p_memsz = 0x10000;
phdr.p_flags = PF_R | PF_X;
phdr.p_align = 0x1000;
memory_->SetMemory(0x100, &phdr, sizeof(phdr));
if (machine_type == EM_ARM) {
memset(&phdr, 0, sizeof(phdr));
phdr.p_type = PT_ARM_EXIDX;
phdr.p_offset = 0x30000;
phdr.p_vaddr = 0x30000;
phdr.p_paddr = 0x30000;
phdr.p_filesz = 16;
phdr.p_memsz = 16;
phdr.p_flags = PF_R;
phdr.p_align = 0x4;
memory_->SetMemory(0x100 + sizeof(phdr), &phdr, sizeof(phdr));
}
}
void InitElf64(uint32_t machine_type) {
Elf64_Ehdr ehdr;
TestInitEhdr<Elf64_Ehdr>(&ehdr, ELFCLASS64, machine_type);
ehdr.e_phoff = 0x100;
ehdr.e_flags = 0x5000200;
ehdr.e_ehsize = sizeof(ehdr);
ehdr.e_phentsize = sizeof(Elf64_Phdr);
ehdr.e_phnum = 1;
ehdr.e_shentsize = sizeof(Elf64_Shdr);
memory_->SetMemory(0, &ehdr, sizeof(ehdr));
Elf64_Phdr phdr;
memset(&phdr, 0, sizeof(phdr));
phdr.p_type = PT_LOAD;
phdr.p_filesz = 0x10000;
phdr.p_memsz = 0x10000;
phdr.p_flags = PF_R | PF_X;
phdr.p_align = 0x1000;
memory_->SetMemory(0x100, &phdr, sizeof(phdr));
}
MemoryFake* memory_;
};
TEST_F(ElfTest, invalid_memory) {
Elf elf(memory_);
ASSERT_FALSE(elf.Init(false));
ASSERT_FALSE(elf.valid());
}
TEST_F(ElfTest, elf_invalid) {
Elf elf(memory_);
InitElf32(EM_386);
// Corrupt the ELF signature.
memory_->SetData32(0, 0x7f000000);
ASSERT_FALSE(elf.Init(false));
ASSERT_FALSE(elf.valid());
ASSERT_TRUE(elf.interface() == nullptr);
std::string name;
ASSERT_FALSE(elf.GetSoname(&name));
uint64_t func_offset;
ASSERT_FALSE(elf.GetFunctionName(0, &name, &func_offset));
bool finished;
ASSERT_FALSE(elf.Step(0, 0, nullptr, nullptr, &finished));
}
TEST_F(ElfTest, elf32_invalid_machine) {
Elf elf(memory_);
InitElf32(EM_PPC);
ResetLogs();
ASSERT_FALSE(elf.Init(false));
ASSERT_EQ("", GetFakeLogBuf());
ASSERT_EQ("4 unwind 32 bit elf that is neither arm nor x86: e_machine = 20\n\n",
GetFakeLogPrint());
}
TEST_F(ElfTest, elf64_invalid_machine) {
Elf elf(memory_);
InitElf64(EM_PPC64);
ResetLogs();
ASSERT_FALSE(elf.Init(false));
ASSERT_EQ("", GetFakeLogBuf());
ASSERT_EQ("4 unwind 64 bit elf that is neither aarch64 nor x86_64: e_machine = 21\n\n",
GetFakeLogPrint());
}
TEST_F(ElfTest, elf_arm) {
Elf elf(memory_);
InitElf32(EM_ARM);
ASSERT_TRUE(elf.Init(false));
ASSERT_TRUE(elf.valid());
ASSERT_EQ(static_cast<uint32_t>(EM_ARM), elf.machine_type());
ASSERT_EQ(ELFCLASS32, elf.class_type());
ASSERT_TRUE(elf.interface() != nullptr);
}
TEST_F(ElfTest, elf_x86) {
Elf elf(memory_);
InitElf32(EM_386);
ASSERT_TRUE(elf.Init(false));
ASSERT_TRUE(elf.valid());
ASSERT_EQ(static_cast<uint32_t>(EM_386), elf.machine_type());
ASSERT_EQ(ELFCLASS32, elf.class_type());
ASSERT_TRUE(elf.interface() != nullptr);
}
TEST_F(ElfTest, elf_arm64) {
Elf elf(memory_);
InitElf64(EM_AARCH64);
ASSERT_TRUE(elf.Init(false));
ASSERT_TRUE(elf.valid());
ASSERT_EQ(static_cast<uint32_t>(EM_AARCH64), elf.machine_type());
ASSERT_EQ(ELFCLASS64, elf.class_type());
ASSERT_TRUE(elf.interface() != nullptr);
}
TEST_F(ElfTest, elf_x86_64) {
Elf elf(memory_);
InitElf64(EM_X86_64);
ASSERT_TRUE(elf.Init(false));
ASSERT_TRUE(elf.valid());
ASSERT_EQ(static_cast<uint32_t>(EM_X86_64), elf.machine_type());
ASSERT_EQ(ELFCLASS64, elf.class_type());
ASSERT_TRUE(elf.interface() != nullptr);
}
TEST_F(ElfTest, gnu_debugdata_init_fail32) {
TestInitGnuDebugdata<Elf32_Ehdr, Elf32_Shdr>(ELFCLASS32, EM_ARM, false,
[&](uint64_t offset, const void* ptr, size_t size) {
memory_->SetMemory(offset, ptr, size);
});
Elf elf(memory_);
ASSERT_TRUE(elf.Init(false));
ASSERT_TRUE(elf.interface() != nullptr);
ASSERT_TRUE(elf.gnu_debugdata_interface() == nullptr);
EXPECT_EQ(0x1acU, elf.interface()->gnu_debugdata_offset());
EXPECT_EQ(0x100U, elf.interface()->gnu_debugdata_size());
}
TEST_F(ElfTest, gnu_debugdata_init_fail64) {
TestInitGnuDebugdata<Elf64_Ehdr, Elf64_Shdr>(ELFCLASS64, EM_AARCH64, false,
[&](uint64_t offset, const void* ptr, size_t size) {
memory_->SetMemory(offset, ptr, size);
});
Elf elf(memory_);
ASSERT_TRUE(elf.Init(false));
ASSERT_TRUE(elf.interface() != nullptr);
ASSERT_TRUE(elf.gnu_debugdata_interface() == nullptr);
EXPECT_EQ(0x200U, elf.interface()->gnu_debugdata_offset());
EXPECT_EQ(0x100U, elf.interface()->gnu_debugdata_size());
}
TEST_F(ElfTest, gnu_debugdata_init32) {
TestInitGnuDebugdata<Elf32_Ehdr, Elf32_Shdr>(ELFCLASS32, EM_ARM, true,
[&](uint64_t offset, const void* ptr, size_t size) {
memory_->SetMemory(offset, ptr, size);
});
Elf elf(memory_);
ASSERT_TRUE(elf.Init(true));
ASSERT_TRUE(elf.interface() != nullptr);
ASSERT_TRUE(elf.gnu_debugdata_interface() != nullptr);
EXPECT_EQ(0x1acU, elf.interface()->gnu_debugdata_offset());
EXPECT_EQ(0x8cU, elf.interface()->gnu_debugdata_size());
}
TEST_F(ElfTest, gnu_debugdata_init64) {
TestInitGnuDebugdata<Elf64_Ehdr, Elf64_Shdr>(ELFCLASS64, EM_AARCH64, true,
[&](uint64_t offset, const void* ptr, size_t size) {
memory_->SetMemory(offset, ptr, size);
});
Elf elf(memory_);
ASSERT_TRUE(elf.Init(true));
ASSERT_TRUE(elf.interface() != nullptr);
ASSERT_TRUE(elf.gnu_debugdata_interface() != nullptr);
EXPECT_EQ(0x200U, elf.interface()->gnu_debugdata_offset());
EXPECT_EQ(0x90U, elf.interface()->gnu_debugdata_size());
}
TEST_F(ElfTest, rel_pc) {
ElfFake elf(memory_);
ElfInterfaceFake* interface = new ElfInterfaceFake(memory_);
elf.FakeSetInterface(interface);
elf.FakeSetValid(true);
elf.FakeSetLoadBias(0);
MapInfo map_info(0x1000, 0x2000);
ASSERT_EQ(0x101U, elf.GetRelPc(0x1101, &map_info));
elf.FakeSetLoadBias(0x3000);
ASSERT_EQ(0x3101U, elf.GetRelPc(0x1101, &map_info));
elf.FakeSetValid(false);
elf.FakeSetLoadBias(0);
ASSERT_EQ(0x101U, elf.GetRelPc(0x1101, &map_info));
}
TEST_F(ElfTest, step_in_signal_map) {
ElfFake elf(memory_);
RegsArm regs;
regs[13] = 0x50000;
regs[15] = 0x8000;
regs.SetFromRaw();
ElfInterfaceFake* interface = new ElfInterfaceFake(memory_);
elf.FakeSetInterface(interface);
memory_->SetData32(0x3000, 0xdf0027ad);
MemoryFake process_memory;
process_memory.SetData32(0x50000, 0);
for (size_t i = 0; i < 16; i++) {
process_memory.SetData32(0x500a0 + i * sizeof(uint32_t), i);
}
elf.FakeSetValid(true);
elf.FakeSetLoadBias(0);
bool finished;
ASSERT_TRUE(elf.Step(0x1000, 0x2000, &regs, &process_memory, &finished));
EXPECT_FALSE(finished);
EXPECT_EQ(15U, regs.pc());
EXPECT_EQ(13U, regs.sp());
}
class ElfInterfaceMock : public ElfInterface {
public:
ElfInterfaceMock(Memory* memory) : ElfInterface(memory) {}
virtual ~ElfInterfaceMock() = default;
bool Init(uint64_t*) override { return false; }
void InitHeaders() override {}
bool GetSoname(std::string*) override { return false; }
bool GetFunctionName(uint64_t, uint64_t, std::string*, uint64_t*) override { return false; }
MOCK_METHOD4(Step, bool(uint64_t, Regs*, Memory*, bool*));
};
TEST_F(ElfTest, step_in_interface) {
ElfFake elf(memory_);
elf.FakeSetValid(true);
elf.FakeSetLoadBias(0);
RegsArm regs;
ElfInterfaceMock* interface = new ElfInterfaceMock(memory_);
elf.FakeSetInterface(interface);
MemoryFake process_memory;
bool finished;
EXPECT_CALL(*interface, Step(0x1000, &regs, &process_memory, &finished))
.WillOnce(::testing::Return(true));
ASSERT_TRUE(elf.Step(0x1000, 0x2000, &regs, &process_memory, &finished));
}
TEST_F(ElfTest, step_in_interface_non_zero_load_bias) {
ElfFake elf(memory_);
elf.FakeSetValid(true);
elf.FakeSetLoadBias(0x4000);
RegsArm regs;
ElfInterfaceMock* interface = new ElfInterfaceMock(memory_);
elf.FakeSetInterface(interface);
MemoryFake process_memory;
// Invalid relative pc given load_bias.
bool finished;
ASSERT_FALSE(elf.Step(0x1000, 0x2000, &regs, &process_memory, &finished));
EXPECT_CALL(*interface, Step(0x3300, &regs, &process_memory, &finished))
.WillOnce(::testing::Return(true));
ASSERT_TRUE(elf.Step(0x7300, 0x2000, &regs, &process_memory, &finished));
}
} // namespace unwindstack