Add extra frame when dex_pc is non-zero. (0b06a590) · Commits · e / os / android_system_core

debuggerd/Android.bp

+1 −0

Original line number	Diff line number	Diff line
		@@ -114,6 +114,7 @@ cc_library_static {
		"libbacktrace",
		"libunwind",
		"libunwindstack",
		"libdexfile",
		"liblzma",
		"libcutils",
		],

libbacktrace/Android.bp

+24 −0

Original line number	Diff line number	Diff line
		@@ -50,6 +50,7 @@ libbacktrace_sources = [
		"BacktracePtrace.cpp",
		"thread_utils.c",
		"ThreadEntry.cpp",
		"UnwindDexFile.cpp",
		"UnwindStack.cpp",
		"UnwindStackMap.cpp",
		]
		@@ -92,13 +93,27 @@ cc_library {
		"liblog",
		"libunwind",
		"libunwindstack",
		"libdexfile",
		],

		static_libs: ["libcutils"],

		// libdexfile will eventually properly export headers, for now
		// include these directly.
		include_dirs: [
		"art/runtime",
		],

		header_libs: [ "jni_headers", ],
		},
		android: {
		static_libs: ["libasync_safe"],
		},
		vendor: {
		cflags: ["-DNO_LIBDEXFILE"],
		exclude_srcs: ["UnwindDexFile.cpp"],
		exclude_shared_libs: ["libdexfile"],
		},
		},
		whole_static_libs: ["libdemangle"],
		}
		@@ -161,6 +176,8 @@ cc_test {
		"backtrace_test.cpp",
		"GetPss.cpp",
		"thread_utils.c",

		"unwind_dex_test.cpp",
		],

		cflags: [
		@@ -172,6 +189,7 @@ cc_test {
		shared_libs: [
		"libbacktrace_test",
		"libbacktrace",
		"libdexfile",
		"libbase",
		"libcutils",
		"liblog",
		@@ -212,6 +230,12 @@ cc_test {
		},
		},

		// libdexfile will eventually properly export headers, for now
		// include these directly.
		include_dirs: [
		"art/runtime",
		],

		data: [
		"testdata/arm/*",
		"testdata/arm64/*",

libbacktrace/UnwindDexFile.cpp

0 → 100644

+162 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2018 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 <stdint.h>
		#include <sys/mman.h>
		#include <sys/stat.h>
		#include <sys/types.h>
		#include <unistd.h>

		#include <memory>

		#include <android-base/unique_fd.h>

		#include <dex/code_item_accessors-no_art-inl.h>
		#include <dex/compact_dex_file.h>
		#include <dex/dex_file-inl.h>
		#include <dex/dex_file_loader.h>
		#include <dex/standard_dex_file.h>

		#include <unwindstack/MapInfo.h>
		#include <unwindstack/Memory.h>

		#include "UnwindDexFile.h"

		UnwindDexFile* UnwindDexFile::Create(uint64_t dex_file_offset_in_memory,
		unwindstack::Memory* memory, unwindstack::MapInfo* info) {
		if (!info->name.empty()) {
		std::unique_ptr<UnwindDexFileFromFile> dex_file(new UnwindDexFileFromFile);
		if (dex_file->Open(dex_file_offset_in_memory - info->start + info->offset, info->name)) {
		return dex_file.release();
		}
		}

		std::unique_ptr<UnwindDexFileFromMemory> dex_file(new UnwindDexFileFromMemory);
		if (dex_file->Open(dex_file_offset_in_memory, memory)) {
		return dex_file.release();
		}
		return nullptr;
		}

		void UnwindDexFile::GetMethodInformation(uint64_t dex_offset, std::string* method_name,
		uint64_t* method_offset) {
		if (dex_file_ == nullptr) {
		return;
		}

		for (uint32_t i = 0; i < dex_file_->NumClassDefs(); ++i) {
		const art::DexFile::ClassDef& class_def = dex_file_->GetClassDef(i);
		const uint8_t* class_data = dex_file_->GetClassData(class_def);
		if (class_data == nullptr) {
		continue;
		}
		for (art::ClassDataItemIterator it(*dex_file_.get(), class_data); it.HasNext(); it.Next()) {
		if (!it.IsAtMethod()) {
		continue;
		}
		const art::DexFile::CodeItem* code_item = it.GetMethodCodeItem();
		if (code_item == nullptr) {
		continue;
		}
		art::CodeItemInstructionAccessor code(*dex_file_.get(), code_item);
		if (!code.HasCodeItem()) {
		continue;
		}

		uint64_t offset = reinterpret_cast<const uint8_t*>(code.Insns()) - dex_file_->Begin();
		size_t size = code.InsnsSizeInCodeUnits() * sizeof(uint16_t);
		if (offset <= dex_offset && dex_offset < offset + size) {
		*method_name = dex_file_->PrettyMethod(it.GetMemberIndex(), false);
		*method_offset = dex_offset - offset;
		return;
		}
		}
		}
		}

		UnwindDexFileFromFile::~UnwindDexFileFromFile() {
		if (size_ != 0) {
		munmap(mapped_memory_, size_);
		}
		}

		bool UnwindDexFileFromFile::Open(uint64_t dex_file_offset_in_file, const std::string& file) {
		android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(file.c_str(), O_RDONLY \| O_CLOEXEC)));
		if (fd == -1) {
		return false;
		}
		struct stat buf;
		if (fstat(fd, &buf) == -1) {
		return false;
		}
		uint64_t length;
		if (buf.st_size < 0 \|\|
		__builtin_add_overflow(dex_file_offset_in_file, sizeof(art::DexFile::Header), &length) \|\|
		static_cast<uint64_t>(buf.st_size) < length) {
		return false;
		}

		mapped_memory_ = mmap(nullptr, buf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
		if (mapped_memory_ == MAP_FAILED) {
		return false;
		}
		size_ = buf.st_size;

		uint8_t* memory = reinterpret_cast<uint8_t*>(mapped_memory_);

		art::DexFile::Header* header =
		reinterpret_cast<art::DexFile::Header*>(&memory[dex_file_offset_in_file]);
		if (!art::StandardDexFile::IsMagicValid(header->magic_) &&
		!art::CompactDexFile::IsMagicValid(header->magic_)) {
		return false;
		}

		if (__builtin_add_overflow(dex_file_offset_in_file, header->file_size_, &length) \|\|
		static_cast<uint64_t>(buf.st_size) < length) {
		return false;
		}

		art::DexFileLoader loader;
		std::string error_msg;
		auto dex = loader.Open(&memory[dex_file_offset_in_file], header->file_size_, "", 0, nullptr,
		false, false, &error_msg);
		dex_file_.reset(dex.release());
		return dex_file_ != nullptr;
		}

		bool UnwindDexFileFromMemory::Open(uint64_t dex_file_offset_in_memory, unwindstack::Memory* memory) {
		art::DexFile::Header header;
		if (!memory->ReadFully(dex_file_offset_in_memory, &header, sizeof(header))) {
		return false;
		}

		if (!art::StandardDexFile::IsMagicValid(header.magic_) &&
		!art::CompactDexFile::IsMagicValid(header.magic_)) {
		return false;
		}

		memory_.resize(header.file_size_);
		if (!memory->ReadFully(dex_file_offset_in_memory, memory_.data(), header.file_size_)) {
		return false;
		}

		art::DexFileLoader loader;
		std::string error_msg;
		auto dex =
		loader.Open(memory_.data(), header.file_size_, "", 0, nullptr, false, false, &error_msg);
		dex_file_.reset(dex.release());
		return dex_file_ != nullptr;
		}

libbacktrace/UnwindDexFile.h

0 → 100644

+70 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2018 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.
		*/

		#ifndef _LIBBACKTRACE_UNWIND_DEX_FILE_H
		#define _LIBBACKTRACE_UNWIND_DEX_FILE_H

		#include <stdint.h>

		#include <memory>
		#include <string>
		#include <vector>

		#include <dex/dex_file-inl.h>

		namespace unwindstack {
		class Memory;
		struct MapInfo;
		} // namespace unwindstack

		class UnwindDexFile {
		public:
		UnwindDexFile() = default;
		virtual ~UnwindDexFile() = default;

		void GetMethodInformation(uint64_t dex_offset, std::string* method_name, uint64_t* method_offset);

		static UnwindDexFile* Create(uint64_t dex_file_offset_in_memory, unwindstack::Memory* memory,
		unwindstack::MapInfo* info);

		protected:
		std::unique_ptr<const art::DexFile> dex_file_;
		};

		class UnwindDexFileFromFile : public UnwindDexFile {
		public:
		UnwindDexFileFromFile() = default;
		virtual ~UnwindDexFileFromFile();

		bool Open(uint64_t dex_file_offset_in_file, const std::string& name);

		private:
		void* mapped_memory_ = nullptr;
		size_t size_ = 0;
		};

		class UnwindDexFileFromMemory : public UnwindDexFile {
		public:
		UnwindDexFileFromMemory() = default;
		virtual ~UnwindDexFileFromMemory() = default;

		bool Open(uint64_t dex_file_offset_in_memory, unwindstack::Memory* memory);

		private:
		std::vector<uint8_t> memory_;
		};

		#endif // _LIBBACKTRACE_UNWIND_DEX_FILE_H

libbacktrace/UnwindStack.cpp

+80 −3

Original line number	Diff line number	Diff line
		@@ -40,9 +40,67 @@
		#include <unwindstack/Unwinder.h>

		#include "BacktraceLog.h"
		#ifndef NO_LIBDEXFILE
		#include "UnwindDexFile.h"
		#endif
		#include "UnwindStack.h"
		#include "UnwindStackMap.h"

		static void FillInDexFrame(UnwindStackMap* stack_map, uint64_t dex_pc,
		backtrace_frame_data_t* frame) {
		// The DEX PC points into the .dex section within an ELF file.
		// However, this is a BBS section manually mmaped to a .vdex file,
		// so we need to get the following map to find the ELF data.
		unwindstack::Maps* maps = stack_map->stack_maps();
		auto it = maps->begin();
		uint64_t rel_dex_pc;
		unwindstack::MapInfo* info;
		for (; it != maps->end(); ++it) {
		auto entry = *it;
		if (dex_pc >= entry->start && dex_pc < entry->end) {
		info = entry;
		rel_dex_pc = dex_pc - entry->start;
		frame->map.start = entry->start;
		frame->map.end = entry->end;
		frame->map.offset = entry->offset;
		frame->map.load_bias = entry->load_bias;
		frame->map.flags = entry->flags;
		frame->map.name = entry->name;
		frame->rel_pc = rel_dex_pc;
		break;
		}
		}
		if (it == maps->end() \|\| ++it == maps->end()) {
		return;
		}

		auto entry = *it;
		auto process_memory = stack_map->process_memory();
		unwindstack::Elf* elf = entry->GetElf(process_memory, true);
		if (!elf->valid()) {
		return;
		}

		// Adjust the relative dex by the offset.
		rel_dex_pc += entry->elf_offset;

		uint64_t dex_offset;
		if (!elf->GetFunctionName(rel_dex_pc, &frame->func_name, &dex_offset)) {
		return;
		}
		frame->func_offset = dex_offset;
		if (frame->func_name != "$dexfile") {
		return;
		}

		#ifndef NO_LIBDEXFILE
		UnwindDexFile* dex_file = stack_map->GetDexFile(dex_pc - dex_offset, info);
		if (dex_file != nullptr) {
		dex_file->GetMethodInformation(dex_offset, &frame->func_name, &frame->func_offset);
		}
		#endif
		}

		bool Backtrace::Unwind(unwindstack::Regs* regs, BacktraceMap* back_map,
		std::vector<backtrace_frame_data_t>* frames, size_t num_ignore_frames,
		std::vector<std::string>* skip_names) {
		@@ -60,19 +118,25 @@ bool Backtrace::Unwind(unwindstack::Regs* regs, BacktraceMap* back_map,
		return true;
		}

		frames->resize(unwinder.NumFrames() - num_ignore_frames);
		auto unwinder_frames = unwinder.frames();
		// Get the real number of frames we'll need.
		size_t total_frames = 0;
		for (size_t i = num_ignore_frames; i < unwinder.NumFrames(); i++, total_frames++) {
		if (unwinder_frames[i].dex_pc != 0) {
		total_frames++;
		}
		}
		frames->resize(total_frames);
		size_t cur_frame = 0;
		for (size_t i = num_ignore_frames; i < unwinder.NumFrames(); i++, cur_frame++) {
		auto frame = &unwinder_frames[i];
		backtrace_frame_data_t* back_frame = &frames->at(cur_frame);

		back_frame->num = frame->num - num_ignore_frames;
		back_frame->num = cur_frame;

		back_frame->rel_pc = frame->rel_pc;
		back_frame->pc = frame->pc;
		back_frame->sp = frame->sp;
		back_frame->dex_pc = frame->dex_pc;

		back_frame->func_name = demangle(frame->function_name.c_str());
		back_frame->func_offset = frame->function_offset;
		@@ -83,6 +147,19 @@ bool Backtrace::Unwind(unwindstack::Regs* regs, BacktraceMap* back_map,
		back_frame->map.offset = frame->map_offset;
		back_frame->map.load_bias = frame->map_load_bias;
		back_frame->map.flags = frame->map_flags;

		// Inject a frame that represents the dex pc data.
		if (frame->dex_pc != 0) {
		cur_frame++;
		backtrace_frame_data_t* dex_frame = &frames->at(cur_frame);
		dex_frame->num = cur_frame;
		dex_frame->pc = frame->dex_pc;
		dex_frame->rel_pc = frame->dex_pc;
		dex_frame->sp = back_frame->sp;
		dex_frame->stack_size = 0;
		dex_frame->func_offset = 0;
		FillInDexFrame(stack_map, frame->dex_pc, dex_frame);
		}
		}

		return true;