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// Copyright (c) 2010, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// exception_handler_test.cc: Unit tests for google_breakpad::ExceptionHandler
#include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h>
#include "breakpad_googletest_includes.h"
#include "client/mac/handler/exception_handler.h"
#include "client/mac/tests/auto_tempdir.h"
#include "common/mac/MachIPC.h"
#include "google_breakpad/processor/minidump.h"
namespace google_breakpad {
// This acts as the log sink for INFO logging from the processor
// logging code. The logging output confuses XCode and makes it think
// there are unit test failures. testlogging.h handles the overriding.
std::ostringstream info_log;
}
namespace {
using std::string;
using google_breakpad::AutoTempDir;
using google_breakpad::ExceptionHandler;
using google_breakpad::MachPortSender;
using google_breakpad::MachReceiveMessage;
using google_breakpad::MachSendMessage;
using google_breakpad::Minidump;
using google_breakpad::MinidumpContext;
using google_breakpad::MinidumpException;
using google_breakpad::MinidumpMemoryList;
using google_breakpad::MinidumpMemoryRegion;
using google_breakpad::ReceivePort;
using testing::Test;
class ExceptionHandlerTest : public Test {
public:
AutoTempDir tempDir;
string lastDumpName;
};
static void Crasher() {
int *a = (int*)0x42;
fprintf(stdout, "Going to crash...\n");
fprintf(stdout, "A = %d", *a);
}
static void SoonToCrash() {
Crasher();
}
static bool MDCallback(const char *dump_dir, const char *file_name,
void *context, bool success) {
string path(dump_dir);
path.append("/");
path.append(file_name);
path.append(".dmp");
int fd = *reinterpret_cast<int*>(context);
(void)write(fd, path.c_str(), path.length() + 1);
close(fd);
exit(0);
// not reached
return true;
}
TEST_F(ExceptionHandlerTest, InProcess) {
// Give the child process a pipe to report back on.
int fds[2];
ASSERT_EQ(0, pipe(fds));
// Fork off a child process so it can crash.
pid_t pid = fork();
if (pid == 0) {
// In the child process.
close(fds[0]);
ExceptionHandler eh(tempDir.path, NULL, MDCallback, &fds[1], true, NULL);
// crash
SoonToCrash();
// not reached
exit(1);
}
// In the parent process.
ASSERT_NE(-1, pid);
// Wait for the background process to return the minidump file.
close(fds[1]);
char minidump_file[PATH_MAX];
ssize_t nbytes = read(fds[0], minidump_file, sizeof(minidump_file));
ASSERT_NE(0, nbytes);
// Ensure that minidump file exists and is > 0 bytes.
struct stat st;
ASSERT_EQ(0, stat(minidump_file, &st));
ASSERT_LT(0, st.st_size);
// Child process should have exited with a zero status.
int ret;
ASSERT_EQ(pid, waitpid(pid, &ret, 0));
EXPECT_NE(0, WIFEXITED(ret));
EXPECT_EQ(0, WEXITSTATUS(ret));
}
static bool ChildMDCallback(const char *dump_dir, const char *file_name,
void *context, bool success) {
ExceptionHandlerTest *self = reinterpret_cast<ExceptionHandlerTest*>(context);
if (dump_dir && file_name) {
self->lastDumpName = dump_dir;
self->lastDumpName += "/";
self->lastDumpName += file_name;
self->lastDumpName += ".dmp";
}
return true;
}
TEST_F(ExceptionHandlerTest, DumpChildProcess) {
const int kTimeoutMs = 2000;
// Create a mach port to receive the child task on.
char machPortName[128];
sprintf(machPortName, "ExceptionHandlerTest.%d", getpid());
ReceivePort parent_recv_port(machPortName);
// Give the child process a pipe to block on.
int fds[2];
ASSERT_EQ(0, pipe(fds));
// Fork off a child process to dump.
pid_t pid = fork();
if (pid == 0) {
// In the child process
close(fds[0]);
// Send parent process the task and thread ports.
MachSendMessage child_message(0);
child_message.AddDescriptor(mach_task_self());
child_message.AddDescriptor(mach_thread_self());
MachPortSender child_sender(machPortName);
if (child_sender.SendMessage(child_message, kTimeoutMs) != KERN_SUCCESS)
exit(1);
// Wait for the parent process.
uint8_t data;
read(fds[1], &data, 1);
exit(0);
}
// In the parent process.
ASSERT_NE(-1, pid);
close(fds[1]);
// Read the child's task and thread ports.
MachReceiveMessage child_message;
ASSERT_EQ(KERN_SUCCESS,
parent_recv_port.WaitForMessage(&child_message, kTimeoutMs));
mach_port_t child_task = child_message.GetTranslatedPort(0);
mach_port_t child_thread = child_message.GetTranslatedPort(1);
ASSERT_NE((mach_port_t)MACH_PORT_NULL, child_task);
ASSERT_NE((mach_port_t)MACH_PORT_NULL, child_thread);
// Write a minidump of the child process.
bool result = ExceptionHandler::WriteMinidumpForChild(child_task,
child_thread,
tempDir.path,
ChildMDCallback,
this);
ASSERT_EQ(true, result);
// Ensure that minidump file exists and is > 0 bytes.
ASSERT_FALSE(lastDumpName.empty());
struct stat st;
ASSERT_EQ(0, stat(lastDumpName.c_str(), &st));
ASSERT_LT(0, st.st_size);
// Unblock child process
uint8_t data = 1;
(void)write(fds[0], &data, 1);
// Child process should have exited with a zero status.
int ret;
ASSERT_EQ(pid, waitpid(pid, &ret, 0));
EXPECT_NE(0, WIFEXITED(ret));
EXPECT_EQ(0, WEXITSTATUS(ret));
}
// Test that memory around the instruction pointer is written
// to the dump as a MinidumpMemoryRegion.
TEST_F(ExceptionHandlerTest, InstructionPointerMemory) {
// Give the child process a pipe to report back on.
int fds[2];
ASSERT_EQ(0, pipe(fds));
// These are defined here so the parent can use them to check the
// data from the minidump afterwards.
const u_int32_t kMemorySize = 256; // bytes
const int kOffset = kMemorySize / 2;
// This crashes with SIGILL on x86/x86-64/arm.
const unsigned char instructions[] = { 0xff, 0xff, 0xff, 0xff };
pid_t pid = fork();
if (pid == 0) {
close(fds[0]);
ExceptionHandler eh(tempDir.path, NULL, MDCallback, &fds[1], true, NULL);
// Get some executable memory.
char* memory =
reinterpret_cast<char*>(mmap(NULL,
kMemorySize,
PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_PRIVATE | MAP_ANON,
-1,
0));
if (!memory)
exit(0);
// Write some instructions that will crash. Put them in the middle
// of the block of memory, because the minidump should contain 128
// bytes on either side of the instruction pointer.
memcpy(memory + kOffset, instructions, sizeof(instructions));
// Now execute the instructions, which should crash.
typedef void (*void_function)(void);
void_function memory_function =
reinterpret_cast<void_function>(memory + kOffset);
memory_function();
// not reached
exit(1);
}
// In the parent process.
ASSERT_NE(-1, pid);
close(fds[1]);
// Wait for the background process to return the minidump file.
close(fds[1]);
char minidump_file[PATH_MAX];
ssize_t nbytes = read(fds[0], minidump_file, sizeof(minidump_file));
ASSERT_NE(0, nbytes);
// Ensure that minidump file exists and is > 0 bytes.
struct stat st;
ASSERT_EQ(0, stat(minidump_file, &st));
ASSERT_LT(0, st.st_size);
// Child process should have exited with a zero status.
int ret;
ASSERT_EQ(pid, waitpid(pid, &ret, 0));
EXPECT_NE(0, WIFEXITED(ret));
EXPECT_EQ(0, WEXITSTATUS(ret));
// Read the minidump. Locate the exception record and the
// memory list, and then ensure that there is a memory region
// in the memory list that covers the instruction pointer from
// the exception record.
Minidump minidump(minidump_file);
ASSERT_TRUE(minidump.Read());
MinidumpException* exception = minidump.GetException();
MinidumpMemoryList* memory_list = minidump.GetMemoryList();
ASSERT_TRUE(exception);
ASSERT_TRUE(memory_list);
ASSERT_NE((unsigned int)0, memory_list->region_count());
MinidumpContext* context = exception->GetContext();
ASSERT_TRUE(context);
u_int64_t instruction_pointer;
switch (context->GetContextCPU()) {
case MD_CONTEXT_X86:
instruction_pointer = context->GetContextX86()->eip;
break;
case MD_CONTEXT_AMD64:
instruction_pointer = context->GetContextAMD64()->rip;
break;
case MD_CONTEXT_ARM:
instruction_pointer = context->GetContextARM()->iregs[15];
break;
default:
FAIL() << "Unknown context CPU: " << context->GetContextCPU();
break;
}
MinidumpMemoryRegion* region =
memory_list->GetMemoryRegionForAddress(instruction_pointer);
EXPECT_TRUE(region);
EXPECT_EQ(kMemorySize, region->GetSize());
const u_int8_t* bytes = region->GetMemory();
ASSERT_TRUE(bytes);
u_int8_t prefix_bytes[kOffset];
u_int8_t suffix_bytes[kMemorySize - kOffset - sizeof(instructions)];
memset(prefix_bytes, 0, sizeof(prefix_bytes));
memset(suffix_bytes, 0, sizeof(suffix_bytes));
EXPECT_TRUE(memcmp(bytes, prefix_bytes, sizeof(prefix_bytes)) == 0);
EXPECT_TRUE(memcmp(bytes + kOffset, instructions, sizeof(instructions)) == 0);
EXPECT_TRUE(memcmp(bytes + kOffset + sizeof(instructions),
suffix_bytes, sizeof(suffix_bytes)) == 0);
}
// Test that the memory region around the instruction pointer is
// bounded correctly on the low end.
TEST_F(ExceptionHandlerTest, InstructionPointerMemoryMinBound) {
// Give the child process a pipe to report back on.
int fds[2];
ASSERT_EQ(0, pipe(fds));
// These are defined here so the parent can use them to check the
// data from the minidump afterwards.
const u_int32_t kMemorySize = 256; // bytes
const int kOffset = 0;
// This crashes with SIGILL on x86/x86-64/arm.
const unsigned char instructions[] = { 0xff, 0xff, 0xff, 0xff };
pid_t pid = fork();
if (pid == 0) {
close(fds[0]);
ExceptionHandler eh(tempDir.path, NULL, MDCallback, &fds[1], true, NULL);
// Get some executable memory.
char* memory =
reinterpret_cast<char*>(mmap(NULL,
kMemorySize,
PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_PRIVATE | MAP_ANON,
-1,
0));
if (!memory)
exit(0);
// Write some instructions that will crash. Put them at the start
// of the block of memory, to ensure that the memory bounding
// works properly.
memcpy(memory + kOffset, instructions, sizeof(instructions));
// Now execute the instructions, which should crash.
typedef void (*void_function)(void);
void_function memory_function =
reinterpret_cast<void_function>(memory + kOffset);
memory_function();
// not reached
exit(1);
}
// In the parent process.
ASSERT_NE(-1, pid);
close(fds[1]);
// Wait for the background process to return the minidump file.
close(fds[1]);
char minidump_file[PATH_MAX];
ssize_t nbytes = read(fds[0], minidump_file, sizeof(minidump_file));
ASSERT_NE(0, nbytes);
// Ensure that minidump file exists and is > 0 bytes.
struct stat st;
ASSERT_EQ(0, stat(minidump_file, &st));
ASSERT_LT(0, st.st_size);
// Child process should have exited with a zero status.
int ret;
ASSERT_EQ(pid, waitpid(pid, &ret, 0));
EXPECT_NE(0, WIFEXITED(ret));
EXPECT_EQ(0, WEXITSTATUS(ret));
// Read the minidump. Locate the exception record and the
// memory list, and then ensure that there is a memory region
// in the memory list that covers the instruction pointer from
// the exception record.
Minidump minidump(minidump_file);
ASSERT_TRUE(minidump.Read());
MinidumpException* exception = minidump.GetException();
MinidumpMemoryList* memory_list = minidump.GetMemoryList();
ASSERT_TRUE(exception);
ASSERT_TRUE(memory_list);
ASSERT_NE((unsigned int)0, memory_list->region_count());
MinidumpContext* context = exception->GetContext();
ASSERT_TRUE(context);
u_int64_t instruction_pointer;
switch (context->GetContextCPU()) {
case MD_CONTEXT_X86:
instruction_pointer = context->GetContextX86()->eip;
break;
case MD_CONTEXT_AMD64:
instruction_pointer = context->GetContextAMD64()->rip;
break;
case MD_CONTEXT_ARM:
instruction_pointer = context->GetContextARM()->iregs[15];
break;
default:
FAIL() << "Unknown context CPU: " << context->GetContextCPU();
break;
}
MinidumpMemoryRegion* region =
memory_list->GetMemoryRegionForAddress(instruction_pointer);
EXPECT_TRUE(region);
EXPECT_EQ(kMemorySize / 2, region->GetSize());
const u_int8_t* bytes = region->GetMemory();
ASSERT_TRUE(bytes);
u_int8_t suffix_bytes[kMemorySize / 2 - sizeof(instructions)];
memset(suffix_bytes, 0, sizeof(suffix_bytes));
EXPECT_TRUE(memcmp(bytes + kOffset, instructions, sizeof(instructions)) == 0);
EXPECT_TRUE(memcmp(bytes + kOffset + sizeof(instructions),
suffix_bytes, sizeof(suffix_bytes)) == 0);
}
// Test that the memory region around the instruction pointer is
// bounded correctly on the high end.
TEST_F(ExceptionHandlerTest, InstructionPointerMemoryMaxBound) {
// Give the child process a pipe to report back on.
int fds[2];
ASSERT_EQ(0, pipe(fds));
// These are defined here so the parent can use them to check the
// data from the minidump afterwards.
// Use 4k here because the OS will hand out a single page even
// if a smaller size is requested, and this test wants to
// test the upper bound of the memory range.
const u_int32_t kMemorySize = 4096; // bytes
// This crashes with SIGILL on x86/x86-64/arm.
const unsigned char instructions[] = { 0xff, 0xff, 0xff, 0xff };
const int kOffset = kMemorySize - sizeof(instructions);
pid_t pid = fork();
if (pid == 0) {
close(fds[0]);
ExceptionHandler eh(tempDir.path, NULL, MDCallback, &fds[1], true, NULL);
// Get some executable memory.
char* memory =
reinterpret_cast<char*>(mmap(NULL,
kMemorySize,
PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_PRIVATE | MAP_ANON,
-1,
0));
if (!memory)
exit(0);
// Write some instructions that will crash. Put them at the start
// of the block of memory, to ensure that the memory bounding
// works properly.
memcpy(memory + kOffset, instructions, sizeof(instructions));
// Now execute the instructions, which should crash.
typedef void (*void_function)(void);
void_function memory_function =
reinterpret_cast<void_function>(memory + kOffset);
memory_function();
// not reached
exit(1);
}
// In the parent process.
ASSERT_NE(-1, pid);
close(fds[1]);
// Wait for the background process to return the minidump file.
close(fds[1]);
char minidump_file[PATH_MAX];
ssize_t nbytes = read(fds[0], minidump_file, sizeof(minidump_file));
ASSERT_NE(0, nbytes);
// Ensure that minidump file exists and is > 0 bytes.
struct stat st;
ASSERT_EQ(0, stat(minidump_file, &st));
ASSERT_LT(0, st.st_size);
// Child process should have exited with a zero status.
int ret;
ASSERT_EQ(pid, waitpid(pid, &ret, 0));
EXPECT_NE(0, WIFEXITED(ret));
EXPECT_EQ(0, WEXITSTATUS(ret));
// Read the minidump. Locate the exception record and the
// memory list, and then ensure that there is a memory region
// in the memory list that covers the instruction pointer from
// the exception record.
Minidump minidump(minidump_file);
ASSERT_TRUE(minidump.Read());
MinidumpException* exception = minidump.GetException();
MinidumpMemoryList* memory_list = minidump.GetMemoryList();
ASSERT_TRUE(exception);
ASSERT_TRUE(memory_list);
ASSERT_NE((unsigned int)0, memory_list->region_count());
MinidumpContext* context = exception->GetContext();
ASSERT_TRUE(context);
u_int64_t instruction_pointer;
switch (context->GetContextCPU()) {
case MD_CONTEXT_X86:
instruction_pointer = context->GetContextX86()->eip;
break;
case MD_CONTEXT_AMD64:
instruction_pointer = context->GetContextAMD64()->rip;
break;
case MD_CONTEXT_ARM:
instruction_pointer = context->GetContextARM()->iregs[15];
break;
default:
FAIL() << "Unknown context CPU: " << context->GetContextCPU();
break;
}
MinidumpMemoryRegion* region =
memory_list->GetMemoryRegionForAddress(instruction_pointer);
EXPECT_TRUE(region);
const size_t kPrefixSize = 128; // bytes
EXPECT_EQ(kPrefixSize + sizeof(instructions), region->GetSize());
const u_int8_t* bytes = region->GetMemory();
ASSERT_TRUE(bytes);
u_int8_t prefix_bytes[kPrefixSize];
memset(prefix_bytes, 0, sizeof(prefix_bytes));
EXPECT_TRUE(memcmp(bytes, prefix_bytes, sizeof(prefix_bytes)) == 0);
EXPECT_TRUE(memcmp(bytes + kPrefixSize,
instructions, sizeof(instructions)) == 0);
}
// Ensure that an extra memory block doesn't get added when the
// instruction pointer is not in mapped memory.
TEST_F(ExceptionHandlerTest, InstructionPointerMemoryNullPointer) {
// Give the child process a pipe to report back on.
int fds[2];
ASSERT_EQ(0, pipe(fds));
pid_t pid = fork();
if (pid == 0) {
close(fds[0]);
ExceptionHandler eh(tempDir.path, NULL, MDCallback, &fds[1], true, NULL);
// Try calling a NULL pointer.
typedef void (*void_function)(void);
void_function memory_function =
reinterpret_cast<void_function>(NULL);
memory_function();
// not reached
exit(1);
}
// In the parent process.
ASSERT_NE(-1, pid);
close(fds[1]);
// Wait for the background process to return the minidump file.
close(fds[1]);
char minidump_file[PATH_MAX];
ssize_t nbytes = read(fds[0], minidump_file, sizeof(minidump_file));
ASSERT_NE(0, nbytes);
// Ensure that minidump file exists and is > 0 bytes.
struct stat st;
ASSERT_EQ(0, stat(minidump_file, &st));
ASSERT_LT(0, st.st_size);
// Child process should have exited with a zero status.
int ret;
ASSERT_EQ(pid, waitpid(pid, &ret, 0));
EXPECT_NE(0, WIFEXITED(ret));
EXPECT_EQ(0, WEXITSTATUS(ret));
// Read the minidump. Locate the exception record and the
// memory list, and then ensure that there is only one memory region
// in the memory list (the thread memory from the single thread).
Minidump minidump(minidump_file);
ASSERT_TRUE(minidump.Read());
MinidumpException* exception = minidump.GetException();
MinidumpMemoryList* memory_list = minidump.GetMemoryList();
ASSERT_TRUE(exception);
ASSERT_TRUE(memory_list);
ASSERT_EQ((unsigned int)1, memory_list->region_count());
}
}
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