snapshot/linux/debug_rendezvous_test.cc - crashpad/crashpad - Git at Google

 // Copyright 2017 The Crashpad Authors
 //
 // 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 "snapshot/linux/debug_rendezvous.h"

 #include <linux/auxvec.h>
 #include <string.h>
 #include <unistd.h>

 #include <limits>

 #include "base/format_macros.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_piece.h"
 #include "base/strings/stringprintf.h"
 #include "build/build_config.h"
 #include "gtest/gtest.h"
 #include "snapshot/elf/elf_image_reader.h"
 #include "snapshot/linux/test_modules.h"
 #include "test/linux/fake_ptrace_connection.h"
 #include "test/main_arguments.h"
 #include "test/multiprocess.h"
 #include "util/linux/address_types.h"
 #include "util/linux/auxiliary_vector.h"
 #include "util/linux/direct_ptrace_connection.h"
 #include "util/linux/memory_map.h"
 #include "util/misc/address_sanitizer.h"
 #include "util/misc/memory_sanitizer.h"
 #include "util/numeric/safe_assignment.h"
 #include "util/process/process_memory_linux.h"
 #include "util/process/process_memory_range.h"

 #if BUILDFLAG(IS_ANDROID)
 #include <android/api-level.h>
 #endif

 namespace crashpad {
 namespace test {
 namespace {

 void ExpectLoadBias(bool is_64_bit,
                     VMAddress unsigned_bias,
                     VMOffset signed_bias) {
   if (is_64_bit) {
     EXPECT_EQ(unsigned_bias, static_cast<VMAddress>(signed_bias));
   } else {
     uint32_t unsigned_bias32;
     ASSERT_TRUE(AssignIfInRange(&unsigned_bias32, unsigned_bias));

     uint32_t casted_bias32 = static_cast<uint32_t>(signed_bias);
     EXPECT_EQ(unsigned_bias32, casted_bias32);
   }
 }

 void TestAgainstTarget(PtraceConnection* connection) {
   // Use ElfImageReader on the main executable which can tell us the debug
   // address. glibc declares the symbol _r_debug in link.h which we can use to
   // get the address, but Android does not.
   AuxiliaryVector aux;
   ASSERT_TRUE(aux.Initialize(connection));

   LinuxVMAddress phdrs;
   ASSERT_TRUE(aux.GetValue(AT_PHDR, &phdrs));

   MemoryMap mappings;
   ASSERT_TRUE(mappings.Initialize(connection));

   const MemoryMap::Mapping* phdr_mapping = mappings.FindMapping(phdrs);
   ASSERT_TRUE(phdr_mapping);

   auto exe_mappings = mappings.FindFilePossibleMmapStarts(*phdr_mapping);
   ASSERT_EQ(exe_mappings->Count(), 1u);
   LinuxVMAddress elf_address = exe_mappings->Next()->range.Base();

   ProcessMemoryLinux memory(connection);
   ProcessMemoryRange range;
   ASSERT_TRUE(range.Initialize(&memory, connection->Is64Bit()));

   ElfImageReader exe_reader;
   ASSERT_TRUE(exe_reader.Initialize(range, elf_address));
   LinuxVMAddress debug_address;
   ASSERT_TRUE(exe_reader.GetDebugAddress(&debug_address));

   VMAddress exe_dynamic_address = 0;
   if (exe_reader.GetDynamicArrayAddress(&exe_dynamic_address)) {
     CheckedLinuxAddressRange exe_range(
         connection->Is64Bit(), exe_reader.Address(), exe_reader.Size());
     EXPECT_TRUE(exe_range.ContainsValue(exe_dynamic_address));
   }

   // start the actual tests
   DebugRendezvous debug;
   ASSERT_TRUE(debug.Initialize(range, debug_address));

 #if BUILDFLAG(IS_ANDROID)
   const int android_runtime_api = android_get_device_api_level();
   ASSERT_GE(android_runtime_api, 1);

   base::FilePath exe_name(base::FilePath(GetMainArguments()[0]).BaseName());
   EXPECT_NE(debug.Executable()->name.find(exe_name.value()), std::string::npos);

   // Android's loader doesn't set the dynamic array for the executable in the
   // link map until Android 10.0 (API 29).
   if (android_runtime_api >= 29) {
     EXPECT_EQ(debug.Executable()->dynamic_array, exe_dynamic_address);
   } else {
     EXPECT_EQ(debug.Executable()->dynamic_array, 0u);
   }
 #else
   // glibc's loader implements most of the tested features that Android's was
   // missing but has since gained.
   const int android_runtime_api = std::numeric_limits<int>::max();

   // glibc's loader does not set the name for the executable.
   EXPECT_TRUE(debug.Executable()->name.empty());
   EXPECT_EQ(debug.Executable()->dynamic_array, exe_dynamic_address);
 #endif  // BUILDFLAG(IS_ANDROID)

   // Android's loader doesn't set the load bias until Android 4.3 (API 18).
   if (android_runtime_api >= 18) {
     ExpectLoadBias(connection->Is64Bit(),
                    debug.Executable()->load_bias,
                    exe_reader.GetLoadBias());
   } else {
     EXPECT_EQ(debug.Executable()->load_bias, 0u);
   }

   for (const DebugRendezvous::LinkEntry& module : debug.Modules()) {
     SCOPED_TRACE(base::StringPrintf("name %s, load_bias 0x%" PRIx64
                                     ", dynamic_array 0x%" PRIx64,
                                     module.name.c_str(),
                                     module.load_bias,
                                     module.dynamic_array));
     const bool is_android_loader = (module.name == "/system/bin/linker" ||
                                     module.name == "/system/bin/linker64");

     // Android's loader doesn't set its own dynamic array until Android 4.2
     // (API 17).
     if (is_android_loader && android_runtime_api < 17) {
       EXPECT_EQ(module.dynamic_array, 0u);
       EXPECT_EQ(module.load_bias, 0u);
       continue;
     }

     ASSERT_TRUE(module.dynamic_array);
     const MemoryMap::Mapping* dyn_mapping =
         mappings.FindMapping(module.dynamic_array);
     ASSERT_TRUE(dyn_mapping);

     auto possible_mappings = mappings.FindFilePossibleMmapStarts(*dyn_mapping);
     ASSERT_GE(possible_mappings->Count(), 1u);

     std::unique_ptr<ElfImageReader> module_reader;
 #if !BUILDFLAG(IS_ANDROID)
     const MemoryMap::Mapping* module_mapping = nullptr;
 #endif
     const MemoryMap::Mapping* mapping = nullptr;
     while ((mapping = possible_mappings->Next())) {
       auto parsed_module = std::make_unique<ElfImageReader>();
       VMAddress dynamic_address;
       if (parsed_module->Initialize(
               range, mapping->range.Base(), possible_mappings->Count() == 0) &&
           parsed_module->GetDynamicArrayAddress(&dynamic_address) &&
           dynamic_address == module.dynamic_array) {
         module_reader = std::move(parsed_module);
 #if !BUILDFLAG(IS_ANDROID)
         module_mapping = mapping;
 #endif
         break;
       }
     }
     ASSERT_TRUE(module_reader.get());

 #if BUILDFLAG(IS_ANDROID)
     EXPECT_FALSE(module.name.empty());
 #else
     // glibc's loader doesn't always set the name in the link map for the vdso.
     EXPECT_PRED4(
         [](const std::string mapping_name,
            int device,
            int inode,
            const std::string& module_name) {
           const bool is_vdso_mapping =
               device == 0 && inode == 0 && mapping_name == "[vdso]";
 #if defined(ARCH_CPU_X86)
           static constexpr char kPrefix[] = "linux-gate.so.";
 #else
           static constexpr char kPrefix[] = "linux-vdso.so.";
 #endif
           return is_vdso_mapping ==
                  (module_name.empty() ||
                   module_name.compare(0, strlen(kPrefix), kPrefix) == 0);
         },
         module_mapping->name,
         module_mapping->device,
         module_mapping->inode,
         module.name);
 #endif  // BUILDFLAG(IS_ANDROID)

     // Android's loader stops setting its own load bias after Android 4.4.4
     // (API 20) until Android 6.0 (API 23).
     if (is_android_loader && android_runtime_api > 20 &&
         android_runtime_api < 23) {
       EXPECT_EQ(module.load_bias, 0u);
     } else {
       ExpectLoadBias(connection->Is64Bit(),
                      module.load_bias,
                      static_cast<VMAddress>(module_reader->GetLoadBias()));
     }

     CheckedLinuxAddressRange module_range(
         connection->Is64Bit(), module_reader->Address(), module_reader->Size());
     EXPECT_TRUE(module_range.ContainsValue(module.dynamic_array));
   }
 }

 TEST(DebugRendezvous, Self) {
 #if !defined(ADDRESS_SANITIZER) && !defined(MEMORY_SANITIZER)
   const std::string module_name = "test_module.so";
   const std::string module_soname = "test_module_soname";
   ScopedModuleHandle empty_test_module(
       LoadTestModule(module_name, module_soname));
   ASSERT_TRUE(empty_test_module.valid());
 #endif  // !ADDRESS_SANITIZER && !MEMORY_SANITIZER

   FakePtraceConnection connection;
   ASSERT_TRUE(connection.Initialize(getpid()));

   TestAgainstTarget(&connection);
 }

 class ChildTest : public Multiprocess {
  public:
   ChildTest() {}

   ChildTest(const ChildTest&) = delete;
   ChildTest& operator=(const ChildTest&) = delete;

   ~ChildTest() {}

  private:
   void MultiprocessParent() {
     DirectPtraceConnection connection;
     ASSERT_TRUE(connection.Initialize(ChildPID()));

     TestAgainstTarget(&connection);
   }

   void MultiprocessChild() { CheckedReadFileAtEOF(ReadPipeHandle()); }
 };

 TEST(DebugRendezvous, Child) {
   ChildTest test;
   test.Run();
 }

 }  // namespace
 }  // namespace test
 }  // namespace crashpad
	// Copyright 2017 The Crashpad Authors
	//
	// 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 "snapshot/linux/debug_rendezvous.h"

	#include <linux/auxvec.h>
	#include <string.h>
	#include <unistd.h>

	#include <limits>

	#include "base/format_macros.h"
	#include "base/strings/string_number_conversions.h"
	#include "base/strings/string_piece.h"
	#include "base/strings/stringprintf.h"
	#include "build/build_config.h"
	#include "gtest/gtest.h"
	#include "snapshot/elf/elf_image_reader.h"
	#include "snapshot/linux/test_modules.h"
	#include "test/linux/fake_ptrace_connection.h"
	#include "test/main_arguments.h"
	#include "test/multiprocess.h"
	#include "util/linux/address_types.h"
	#include "util/linux/auxiliary_vector.h"
	#include "util/linux/direct_ptrace_connection.h"
	#include "util/linux/memory_map.h"
	#include "util/misc/address_sanitizer.h"
	#include "util/misc/memory_sanitizer.h"
	#include "util/numeric/safe_assignment.h"
	#include "util/process/process_memory_linux.h"
	#include "util/process/process_memory_range.h"

	#if BUILDFLAG(IS_ANDROID)
	#include <android/api-level.h>
	#endif

	namespace crashpad {
	namespace test {
	namespace {

	void ExpectLoadBias(bool is_64_bit,
	VMAddress unsigned_bias,
	VMOffset signed_bias) {
	if (is_64_bit) {
	EXPECT_EQ(unsigned_bias, static_cast<VMAddress>(signed_bias));
	} else {
	uint32_t unsigned_bias32;
	ASSERT_TRUE(AssignIfInRange(&unsigned_bias32, unsigned_bias));

	uint32_t casted_bias32 = static_cast<uint32_t>(signed_bias);
	EXPECT_EQ(unsigned_bias32, casted_bias32);
	}
	}

	void TestAgainstTarget(PtraceConnection* connection) {
	// Use ElfImageReader on the main executable which can tell us the debug
	// address. glibc declares the symbol _r_debug in link.h which we can use to
	// get the address, but Android does not.
	AuxiliaryVector aux;
	ASSERT_TRUE(aux.Initialize(connection));

	LinuxVMAddress phdrs;
	ASSERT_TRUE(aux.GetValue(AT_PHDR, &phdrs));

	MemoryMap mappings;
	ASSERT_TRUE(mappings.Initialize(connection));

	const MemoryMap::Mapping* phdr_mapping = mappings.FindMapping(phdrs);
	ASSERT_TRUE(phdr_mapping);

	auto exe_mappings = mappings.FindFilePossibleMmapStarts(*phdr_mapping);
	ASSERT_EQ(exe_mappings->Count(), 1u);
	LinuxVMAddress elf_address = exe_mappings->Next()->range.Base();

	ProcessMemoryLinux memory(connection);
	ProcessMemoryRange range;
	ASSERT_TRUE(range.Initialize(&memory, connection->Is64Bit()));

	ElfImageReader exe_reader;
	ASSERT_TRUE(exe_reader.Initialize(range, elf_address));
	LinuxVMAddress debug_address;
	ASSERT_TRUE(exe_reader.GetDebugAddress(&debug_address));

	VMAddress exe_dynamic_address = 0;
	if (exe_reader.GetDynamicArrayAddress(&exe_dynamic_address)) {
	CheckedLinuxAddressRange exe_range(
	connection->Is64Bit(), exe_reader.Address(), exe_reader.Size());
	EXPECT_TRUE(exe_range.ContainsValue(exe_dynamic_address));
	}

	// start the actual tests
	DebugRendezvous debug;
	ASSERT_TRUE(debug.Initialize(range, debug_address));

	#if BUILDFLAG(IS_ANDROID)
	const int android_runtime_api = android_get_device_api_level();
	ASSERT_GE(android_runtime_api, 1);

	base::FilePath exe_name(base::FilePath(GetMainArguments()[0]).BaseName());
	EXPECT_NE(debug.Executable()->name.find(exe_name.value()), std::string::npos);

	// Android's loader doesn't set the dynamic array for the executable in the
	// link map until Android 10.0 (API 29).
	if (android_runtime_api >= 29) {
	EXPECT_EQ(debug.Executable()->dynamic_array, exe_dynamic_address);
	} else {
	EXPECT_EQ(debug.Executable()->dynamic_array, 0u);
	}
	#else
	// glibc's loader implements most of the tested features that Android's was
	// missing but has since gained.
	const int android_runtime_api = std::numeric_limits<int>::max();

	// glibc's loader does not set the name for the executable.
	EXPECT_TRUE(debug.Executable()->name.empty());
	EXPECT_EQ(debug.Executable()->dynamic_array, exe_dynamic_address);
	#endif // BUILDFLAG(IS_ANDROID)

	// Android's loader doesn't set the load bias until Android 4.3 (API 18).
	if (android_runtime_api >= 18) {
	ExpectLoadBias(connection->Is64Bit(),
	debug.Executable()->load_bias,
	exe_reader.GetLoadBias());
	} else {
	EXPECT_EQ(debug.Executable()->load_bias, 0u);
	}

	for (const DebugRendezvous::LinkEntry& module : debug.Modules()) {
	SCOPED_TRACE(base::StringPrintf("name %s, load_bias 0x%" PRIx64
	", dynamic_array 0x%" PRIx64,
	module.name.c_str(),
	module.load_bias,
	module.dynamic_array));
	const bool is_android_loader = (module.name == "/system/bin/linker" \|\|
	module.name == "/system/bin/linker64");

	// Android's loader doesn't set its own dynamic array until Android 4.2
	// (API 17).
	if (is_android_loader && android_runtime_api < 17) {
	EXPECT_EQ(module.dynamic_array, 0u);
	EXPECT_EQ(module.load_bias, 0u);
	continue;
	}

	ASSERT_TRUE(module.dynamic_array);
	const MemoryMap::Mapping* dyn_mapping =
	mappings.FindMapping(module.dynamic_array);
	ASSERT_TRUE(dyn_mapping);

	auto possible_mappings = mappings.FindFilePossibleMmapStarts(*dyn_mapping);
	ASSERT_GE(possible_mappings->Count(), 1u);

	std::unique_ptr<ElfImageReader> module_reader;
	#if !BUILDFLAG(IS_ANDROID)
	const MemoryMap::Mapping* module_mapping = nullptr;
	#endif
	const MemoryMap::Mapping* mapping = nullptr;
	while ((mapping = possible_mappings->Next())) {
	auto parsed_module = std::make_unique<ElfImageReader>();
	VMAddress dynamic_address;
	if (parsed_module->Initialize(
	range, mapping->range.Base(), possible_mappings->Count() == 0) &&
	parsed_module->GetDynamicArrayAddress(&dynamic_address) &&
	dynamic_address == module.dynamic_array) {
	module_reader = std::move(parsed_module);
	#if !BUILDFLAG(IS_ANDROID)
	module_mapping = mapping;
	#endif
	break;
	}
	}
	ASSERT_TRUE(module_reader.get());

	#if BUILDFLAG(IS_ANDROID)
	EXPECT_FALSE(module.name.empty());
	#else
	// glibc's loader doesn't always set the name in the link map for the vdso.
	EXPECT_PRED4(
	[](const std::string mapping_name,
	int device,
	int inode,
	const std::string& module_name) {
	const bool is_vdso_mapping =
	device == 0 && inode == 0 && mapping_name == "[vdso]";
	#if defined(ARCH_CPU_X86)
	static constexpr char kPrefix[] = "linux-gate.so.";
	#else
	static constexpr char kPrefix[] = "linux-vdso.so.";
	#endif
	return is_vdso_mapping ==
	(module_name.empty() \|\|
	module_name.compare(0, strlen(kPrefix), kPrefix) == 0);
	},
	module_mapping->name,
	module_mapping->device,
	module_mapping->inode,
	module.name);
	#endif // BUILDFLAG(IS_ANDROID)

	// Android's loader stops setting its own load bias after Android 4.4.4
	// (API 20) until Android 6.0 (API 23).
	if (is_android_loader && android_runtime_api > 20 &&
	android_runtime_api < 23) {
	EXPECT_EQ(module.load_bias, 0u);
	} else {
	ExpectLoadBias(connection->Is64Bit(),
	module.load_bias,
	static_cast<VMAddress>(module_reader->GetLoadBias()));
	}

	CheckedLinuxAddressRange module_range(
	connection->Is64Bit(), module_reader->Address(), module_reader->Size());
	EXPECT_TRUE(module_range.ContainsValue(module.dynamic_array));
	}
	}

	TEST(DebugRendezvous, Self) {
	#if !defined(ADDRESS_SANITIZER) && !defined(MEMORY_SANITIZER)
	const std::string module_name = "test_module.so";
	const std::string module_soname = "test_module_soname";
	ScopedModuleHandle empty_test_module(
	LoadTestModule(module_name, module_soname));
	ASSERT_TRUE(empty_test_module.valid());
	#endif // !ADDRESS_SANITIZER && !MEMORY_SANITIZER

	FakePtraceConnection connection;
	ASSERT_TRUE(connection.Initialize(getpid()));

	TestAgainstTarget(&connection);
	}

	class ChildTest : public Multiprocess {
	public:
	ChildTest() {}

	ChildTest(const ChildTest&) = delete;
	ChildTest& operator=(const ChildTest&) = delete;

	~ChildTest() {}

	private:
	void MultiprocessParent() {
	DirectPtraceConnection connection;
	ASSERT_TRUE(connection.Initialize(ChildPID()));

	TestAgainstTarget(&connection);
	}

	void MultiprocessChild() { CheckedReadFileAtEOF(ReadPipeHandle()); }
	};

	TEST(DebugRendezvous, Child) {
	ChildTest test;
	test.Run();
	}

	} // namespace
	} // namespace test
	} // namespace crashpad