Do not generate a microdump if there are no webview pointers on the stack.

The stack interest range is passed in MicrodumpExtraInfo from the client.
If the extracted stack does not contain a pointer in this range, then we
assume that this is not a WebView crash, and do not generate a microdump.
If the stack extraction fails, we still generate a microdump (without a
stack).

BUG=664460

Change-Id: Ic762497f76f074a3621c7ec88a8c20ed768b9211
Reviewed-on: https://chromium-review.googlesource.com/412781
Reviewed-by: Primiano Tucci <primiano@chromium.org>
This commit is contained in:
Tobias Sargeant 2016-11-30 16:47:04 +00:00 committed by Tobias Sargeant
parent e6ef06f13d
commit 7a8980997d
3 changed files with 208 additions and 108 deletions

View File

@ -40,11 +40,23 @@ struct MicrodumpExtraInfo {
const char* gpu_fingerprint;
const char* process_type;
// |interest_range_start| and |interest_range_end| specify a range
// in the target process address space. Microdumps are only
// generated if the PC or a word on the captured stack point into
// this range, or |suppress_microdump_based_on_interest_range| is
// false.
bool suppress_microdump_based_on_interest_range;
uintptr_t interest_range_start;
uintptr_t interest_range_end;
MicrodumpExtraInfo()
: build_fingerprint(NULL),
product_info(NULL),
gpu_fingerprint(NULL),
process_type(NULL) {}
process_type(NULL),
suppress_microdump_based_on_interest_range(false),
interest_range_start(0),
interest_range_end(0) {}
};
}

View File

@ -141,7 +141,11 @@ class MicrodumpWriter {
dumper_(dumper),
mapping_list_(mappings),
microdump_extra_info_(microdump_extra_info),
log_line_(NULL) {
log_line_(NULL),
stack_copy_(NULL),
stack_len_(0),
stack_lower_bound_(0),
stack_pointer_(0) {
log_line_ = reinterpret_cast<char*>(Alloc(kLineBufferSize));
if (log_line_)
log_line_[0] = '\0'; // Clear out the log line buffer.
@ -159,8 +163,12 @@ class MicrodumpWriter {
return dumper_->ThreadsSuspend() && dumper_->LateInit();
}
bool Dump() {
bool success;
void Dump() {
CaptureResult stack_capture_result = CaptureCrashingThreadStack(-1);
if (stack_capture_result == CAPTURE_UNINTERESTING) {
return;
}
LogLine("-----BEGIN BREAKPAD MICRODUMP-----");
DumpProductInformation();
DumpOSInformation();
@ -169,15 +177,16 @@ class MicrodumpWriter {
#if !defined(__LP64__)
DumpFreeSpace();
#endif
success = DumpCrashingThread();
if (success)
success = DumpMappings();
if (stack_capture_result == CAPTURE_OK)
DumpThreadStack();
DumpCPUState();
DumpMappings();
LogLine("-----END BREAKPAD MICRODUMP-----");
dumper_->ThreadsResume();
return success;
}
private:
enum CaptureResult { CAPTURE_OK, CAPTURE_FAILED, CAPTURE_UNINTERESTING };
// Writes one line to the system log.
void LogLine(const char* msg) {
#if defined(__ANDROID__)
@ -221,7 +230,59 @@ class MicrodumpWriter {
// Writes out the current line buffer on the system log.
void LogCommitLine() {
LogLine(log_line_);
my_strlcpy(log_line_, "", kLineBufferSize);
log_line_[0] = 0;
}
CaptureResult CaptureCrashingThreadStack(int max_stack_len) {
stack_pointer_ = UContextReader::GetStackPointer(ucontext_);
if (!dumper_->GetStackInfo(reinterpret_cast<const void**>(&stack_lower_bound_),
&stack_len_, stack_pointer_)) {
return CAPTURE_FAILED;
}
if (max_stack_len >= 0 &&
stack_len_ > static_cast<size_t>(max_stack_len)) {
stack_len_ = max_stack_len;
}
stack_copy_ = reinterpret_cast<uint8_t*>(Alloc(stack_len_));
dumper_->CopyFromProcess(stack_copy_, dumper_->crash_thread(),
reinterpret_cast<const void*>(stack_lower_bound_),
stack_len_);
if (!microdump_extra_info_.suppress_microdump_based_on_interest_range)
return CAPTURE_OK;
uintptr_t low_addr = microdump_extra_info_.interest_range_start;
uintptr_t high_addr = microdump_extra_info_.interest_range_end;
uintptr_t pc = UContextReader::GetInstructionPointer(ucontext_);
if (low_addr <= pc && pc <= high_addr) return CAPTURE_OK;
// Loop over all stack words that would have been on the stack in
// the target process. (i.e. ones that are >= |stack_pointer_| and
// < |stack_lower_bound_| + |stack_len_| in the target
// process).
// |stack_lower_bound_| is page aligned, and thus also pointer
// aligned. Because the stack pointer might be unaligned, we round
// the offset down to word alignment. |stack_pointer_| >
// |stack_lower_bound_|, so this never results in a negative
// offset.
// Regardless of the alignment of |stack_copy_|, the memory
// starting at |stack_copy_| + |offset| represents an aligned word
// in the target process.
uintptr_t offset =
((stack_pointer_ - stack_lower_bound_) & ~(sizeof(uintptr_t) - 1));
for (uint8_t* sp = stack_copy_ + offset;
sp <= stack_copy_ + stack_len_ - sizeof(uintptr_t);
sp += sizeof(uintptr_t)) {
uintptr_t addr;
my_memcpy(&addr, sp, sizeof(uintptr_t));
if (low_addr <= addr && addr <= high_addr) return CAPTURE_OK;
}
return CAPTURE_UNINTERESTING;
}
void DumpProductInformation() {
@ -315,87 +376,37 @@ class MicrodumpWriter {
LogCommitLine();
}
bool DumpThreadStack(uint32_t thread_id,
uintptr_t stack_pointer,
int max_stack_len,
uint8_t** stack_copy) {
*stack_copy = NULL;
const void* stack;
size_t stack_len;
if (!dumper_->GetStackInfo(&stack, &stack_len, stack_pointer)) {
// The stack pointer might not be available. In this case we don't hard
// fail, just produce a (almost useless) microdump w/o a stack section.
return true;
}
void DumpThreadStack() {
LogAppend("S 0 ");
LogAppend(stack_pointer);
LogAppend(stack_pointer_);
LogAppend(" ");
LogAppend(reinterpret_cast<uintptr_t>(stack));
LogAppend(stack_lower_bound_);
LogAppend(" ");
LogAppend(stack_len);
LogAppend(stack_len_);
LogCommitLine();
if (max_stack_len >= 0 &&
stack_len > static_cast<unsigned int>(max_stack_len)) {
stack_len = max_stack_len;
}
*stack_copy = reinterpret_cast<uint8_t*>(Alloc(stack_len));
dumper_->CopyFromProcess(*stack_copy, thread_id, stack, stack_len);
// Dump the content of the stack, splicing it into chunks which size is
// compatible with the max logcat line size (see LOGGER_ENTRY_MAX_PAYLOAD).
const size_t STACK_DUMP_CHUNK_SIZE = 384;
for (size_t stack_off = 0; stack_off < stack_len;
for (size_t stack_off = 0; stack_off < stack_len_;
stack_off += STACK_DUMP_CHUNK_SIZE) {
LogAppend("S ");
LogAppend(reinterpret_cast<uintptr_t>(stack) + stack_off);
LogAppend(stack_lower_bound_ + stack_off);
LogAppend(" ");
LogAppend(*stack_copy + stack_off,
std::min(STACK_DUMP_CHUNK_SIZE, stack_len - stack_off));
LogAppend(stack_copy_ + stack_off,
std::min(STACK_DUMP_CHUNK_SIZE, stack_len_ - stack_off));
LogCommitLine();
}
return true;
}
// Write information about the crashing thread.
bool DumpCrashingThread() {
const unsigned num_threads = dumper_->threads().size();
for (unsigned i = 0; i < num_threads; ++i) {
MDRawThread thread;
my_memset(&thread, 0, sizeof(thread));
thread.thread_id = dumper_->threads()[i];
// Dump only the crashing thread.
if (static_cast<pid_t>(thread.thread_id) != dumper_->crash_thread())
continue;
assert(ucontext_);
assert(!dumper_->IsPostMortem());
uint8_t* stack_copy;
const uintptr_t stack_ptr = UContextReader::GetStackPointer(ucontext_);
if (!DumpThreadStack(thread.thread_id, stack_ptr, -1, &stack_copy))
return false;
RawContextCPU cpu;
my_memset(&cpu, 0, sizeof(RawContextCPU));
void DumpCPUState() {
RawContextCPU cpu;
my_memset(&cpu, 0, sizeof(RawContextCPU));
#if !defined(__ARM_EABI__) && !defined(__mips__)
UContextReader::FillCPUContext(&cpu, ucontext_, float_state_);
UContextReader::FillCPUContext(&cpu, ucontext_, float_state_);
#else
UContextReader::FillCPUContext(&cpu, ucontext_);
UContextReader::FillCPUContext(&cpu, ucontext_);
#endif
DumpCPUState(&cpu);
}
return true;
}
void DumpCPUState(RawContextCPU* cpu) {
LogAppend("C ");
LogAppend(cpu, sizeof(*cpu));
LogAppend(&cpu, sizeof(cpu));
LogCommitLine();
}
@ -547,7 +558,7 @@ class MicrodumpWriter {
#endif
// Write information about the mappings in effect.
bool DumpMappings() {
void DumpMappings() {
// First write all the mappings from the dumper
for (unsigned i = 0; i < dumper_->mappings().size(); ++i) {
const MappingInfo& mapping = *dumper_->mappings()[i];
@ -566,7 +577,6 @@ class MicrodumpWriter {
++iter) {
DumpModule(iter->first, false, 0, iter->second);
}
return true;
}
void* Alloc(unsigned bytes) { return dumper_->allocator()->Alloc(bytes); }
@ -579,6 +589,20 @@ class MicrodumpWriter {
const MappingList& mapping_list_;
const MicrodumpExtraInfo microdump_extra_info_;
char* log_line_;
// The local copy of crashed process stack memory, beginning at
// |stack_lower_bound_|.
uint8_t* stack_copy_;
// The length of crashed process stack copy.
size_t stack_len_;
// The address of the page containing the stack pointer in the
// crashed process. |stack_lower_bound_| <= |stack_pointer_|
uintptr_t stack_lower_bound_;
// The stack pointer in the crashed process.
uintptr_t stack_pointer_;
};
} // namespace
@ -603,7 +627,8 @@ bool WriteMicrodump(pid_t crashing_process,
MicrodumpWriter writer(context, mappings, microdump_extra_info, &dumper);
if (!writer.Init())
return false;
return writer.Dump();
writer.Dump();
return true;
}
} // namespace google_breakpad

View File

@ -31,6 +31,7 @@
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>
#include <ucontext.h>
#include <sstream>
#include <string>
@ -47,6 +48,11 @@
using namespace google_breakpad;
extern "C" {
extern char __executable_start;
extern char __etext;
}
namespace {
typedef testing::Test MicrodumpWriterTest;
@ -54,18 +60,29 @@ typedef testing::Test MicrodumpWriterTest;
MicrodumpExtraInfo MakeMicrodumpExtraInfo(
const char* build_fingerprint,
const char* product_info,
const char* gpu_fingerprint) {
const char* gpu_fingerprint,
bool suppress_microdump_based_on_interest_range = false,
uintptr_t interest_range_start = 0,
uintptr_t interest_range_end = 0) {
MicrodumpExtraInfo info;
info.build_fingerprint = build_fingerprint;
info.product_info = product_info;
info.gpu_fingerprint = gpu_fingerprint;
info.suppress_microdump_based_on_interest_range =
suppress_microdump_based_on_interest_range;
info.interest_range_start = interest_range_start;
info.interest_range_end = interest_range_end;
return info;
}
void CrashAndGetMicrodump(
const MappingList& mappings,
const MicrodumpExtraInfo& microdump_extra_info,
scoped_array<char>* buf) {
void AssertContainsMicrodump(const std::string& buf) {
ASSERT_NE(std::string::npos, buf.find("-----BEGIN BREAKPAD MICRODUMP-----"));
ASSERT_NE(std::string::npos, buf.find("-----END BREAKPAD MICRODUMP-----"));
}
void CrashAndGetMicrodump(const MappingList& mappings,
const MicrodumpExtraInfo& microdump_extra_info,
std::string* microdump) {
int fds[2];
ASSERT_NE(-1, pipe(fds));
@ -86,7 +103,10 @@ void CrashAndGetMicrodump(
ExceptionHandler::CrashContext context;
memset(&context, 0, sizeof(context));
// Pretend the current context is the child context (which is
// approximately right) so that we have a valid stack pointer, and
// can fetch child stack data via ptrace.
getcontext(&context.context);
// Set a non-zero tid to avoid tripping asserts.
context.tid = child;
@ -105,17 +125,17 @@ void CrashAndGetMicrodump(
// Read back the stderr file and check for the microdump marker.
fsync(err_fd);
lseek(err_fd, 0, SEEK_SET);
const size_t kBufSize = 64 * 1024;
buf->reset(new char[kBufSize]);
ASSERT_GT(read(err_fd, buf->get(), kBufSize), 0);
microdump->clear();
char buf[1024];
while (true) {
int bytes_read = IGNORE_EINTR(read(err_fd, buf, 1024));
if (bytes_read <= 0) break;
microdump->append(buf, buf + bytes_read);
}
close(err_fd);
close(fds[1]);
ASSERT_NE(static_cast<char*>(0), strstr(
buf->get(), "-----BEGIN BREAKPAD MICRODUMP-----"));
ASSERT_NE(static_cast<char*>(0), strstr(
buf->get(), "-----END BREAKPAD MICRODUMP-----"));
}
void CheckMicrodumpContents(const string& microdump_content,
@ -191,23 +211,64 @@ TEST(MicrodumpWriterTest, BasicWithMappings) {
memcpy(mapping.second, kModuleGUID, sizeof(MDGUID));
mappings.push_back(mapping);
scoped_array<char> buf;
std::string buf;
CrashAndGetMicrodump(mappings, MicrodumpExtraInfo(), &buf);
AssertContainsMicrodump(buf);
#ifdef __LP64__
ASSERT_NE(static_cast<char*>(0), strstr(
buf.get(), "M 0000000000001000 000000000000002A 0000000000001000 "
"33221100554477668899AABBCCDDEEFF0 libfoo.so"));
ASSERT_NE(std::string::npos,
buf.find("M 0000000000001000 000000000000002A 0000000000001000 "
"33221100554477668899AABBCCDDEEFF0 libfoo.so"));
#else
ASSERT_NE(static_cast<char*>(0), strstr(
buf.get(), "M 00001000 0000002A 00001000 "
"33221100554477668899AABBCCDDEEFF0 libfoo.so"));
ASSERT_NE(std::string::npos,
buf.find("M 00001000 0000002A 00001000 "
"33221100554477668899AABBCCDDEEFF0 libfoo.so"));
#endif
// In absence of a product info in the minidump, the writer should just write
// an unknown marker.
ASSERT_NE(static_cast<char*>(0), strstr(
buf.get(), "V UNKNOWN:0.0.0.0"));
ASSERT_NE(std::string::npos, buf.find("V UNKNOWN:0.0.0.0"));
}
// Ensure that no output occurs if the interest region is set, but
// doesn't overlap anything on the stack.
TEST(MicrodumpWriterTest, NoOutputIfUninteresting) {
const char kProductInfo[] = "MockProduct:42.0.2311.99";
const char kBuildFingerprint[] =
"aosp/occam/mako:5.1.1/LMY47W/12345678:userdegbug/dev-keys";
const char kGPUFingerprint[] =
"Qualcomm;Adreno (TM) 330;OpenGL ES 3.0 V@104.0 AU@ (GIT@Id3510ff6dc)";
const MicrodumpExtraInfo kMicrodumpExtraInfo(
MakeMicrodumpExtraInfo(kBuildFingerprint, kProductInfo, kGPUFingerprint,
true, 0xdeadbeef, 0xdeadbeef - 1));
std::string buf;
MappingList no_mappings;
CrashAndGetMicrodump(no_mappings, kMicrodumpExtraInfo, &buf);
ASSERT_EQ(0, buf.size());
}
// Ensure that output occurs if the interest region is set, and
// does overlap something on the stack.
TEST(MicrodumpWriterTest, OutputIfInteresting) {
const char kProductInfo[] = "MockProduct:42.0.2311.99";
const char kBuildFingerprint[] =
"aosp/occam/mako:5.1.1/LMY47W/12345678:userdegbug/dev-keys";
const char kGPUFingerprint[] =
"Qualcomm;Adreno (TM) 330;OpenGL ES 3.0 V@104.0 AU@ (GIT@Id3510ff6dc)";
const MicrodumpExtraInfo kMicrodumpExtraInfo(
MakeMicrodumpExtraInfo(kBuildFingerprint, kProductInfo, kGPUFingerprint,
true,
reinterpret_cast<uintptr_t>(&__executable_start),
reinterpret_cast<uintptr_t>(&__etext)));
std::string buf;
MappingList no_mappings;
CrashAndGetMicrodump(no_mappings, kMicrodumpExtraInfo, &buf);
ASSERT_LT(0, buf.size());
}
// Ensure that the product info and build fingerprint metadata show up in the
@ -220,38 +281,40 @@ TEST(MicrodumpWriterTest, BuildFingerprintAndProductInfo) {
"Qualcomm;Adreno (TM) 330;OpenGL ES 3.0 V@104.0 AU@ (GIT@Id3510ff6dc)";
const MicrodumpExtraInfo kMicrodumpExtraInfo(
MakeMicrodumpExtraInfo(kBuildFingerprint, kProductInfo, kGPUFingerprint));
scoped_array<char> buf;
std::string buf;
MappingList no_mappings;
CrashAndGetMicrodump(no_mappings, kMicrodumpExtraInfo, &buf);
CheckMicrodumpContents(string(buf.get()), kMicrodumpExtraInfo);
AssertContainsMicrodump(buf);
CheckMicrodumpContents(buf, kMicrodumpExtraInfo);
}
TEST(MicrodumpWriterTest, NoProductInfo) {
const char kBuildFingerprint[] = "foobar";
const char kGPUFingerprint[] = "bazqux";
scoped_array<char> buf;
std::string buf;
MappingList no_mappings;
const MicrodumpExtraInfo kMicrodumpExtraInfoNoProductInfo(
MakeMicrodumpExtraInfo(kBuildFingerprint, NULL, kGPUFingerprint));
CrashAndGetMicrodump(no_mappings, kMicrodumpExtraInfoNoProductInfo, &buf);
CheckMicrodumpContents(string(buf.get()), kBuildFingerprint,
"UNKNOWN:0.0.0.0", kGPUFingerprint);
AssertContainsMicrodump(buf);
CheckMicrodumpContents(buf, kBuildFingerprint, "UNKNOWN:0.0.0.0",
kGPUFingerprint);
}
TEST(MicrodumpWriterTest, NoGPUInfo) {
const char kProductInfo[] = "bazqux";
const char kBuildFingerprint[] = "foobar";
scoped_array<char> buf;
std::string buf;
MappingList no_mappings;
const MicrodumpExtraInfo kMicrodumpExtraInfoNoGPUInfo(
MakeMicrodumpExtraInfo(kBuildFingerprint, kProductInfo, NULL));
CrashAndGetMicrodump(no_mappings, kMicrodumpExtraInfoNoGPUInfo, &buf);
CheckMicrodumpContents(string(buf.get()), kBuildFingerprint,
kProductInfo, "UNKNOWN");
AssertContainsMicrodump(buf);
CheckMicrodumpContents(buf, kBuildFingerprint, kProductInfo, "UNKNOWN");
}
} // namespace