tequilaOS/platform_system_core
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity
platform_system_core/libunwindstack/DwarfSection.cpp
Christopher Ferris 559c7f2092 Implement new DEX PC lookup scheme. 
GDB wasn't handling the old one gracefully.

- Create a RegsInfo structure that can be used to properly eval expression
  data.
- Remove the versions on Dwarf ops. It doesn't work the in the real world
  and doesn't add useful information.
- Fix dex pc frame number bug.

Test: testrunner.py -j40 --host --cdex-fast -t 137
Test: libunwindstack_test
Test: All unit tests pass.
Change-Id: Iac4fea651b81cb6087fd237a9a5027a352a49245
2018-02-13 16:45:38 -08:00

923 lines
28 KiB
C++
Raw Blame History

/*
* Copyright (C) 2017 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 <unwindstack/DwarfError.h>
#include <unwindstack/DwarfLocation.h>
#include <unwindstack/DwarfMemory.h>
#include <unwindstack/DwarfSection.h>
#include <unwindstack/DwarfStructs.h>
#include <unwindstack/Log.h>
#include <unwindstack/Memory.h>
#include <unwindstack/Regs.h>
#include "DwarfCfa.h"
#include "DwarfDebugFrame.h"
#include "DwarfEhFrame.h"
#include "DwarfEncoding.h"
#include "DwarfOp.h"
#include "RegsInfo.h"
namespace unwindstack {
DwarfSection::DwarfSection(Memory* memory) : memory_(memory) {}
const DwarfFde* DwarfSection::GetFdeFromPc(uint64_t pc) {
uint64_t fde_offset;
if (!GetFdeOffsetFromPc(pc, &fde_offset)) {
return nullptr;
}
const DwarfFde* fde = GetFdeFromOffset(fde_offset);
if (fde == nullptr) {
return nullptr;
}
// Guaranteed pc >= pc_start, need to check pc in the fde range.
if (pc < fde->pc_end) {
return fde;
}
last_error_.code = DWARF_ERROR_ILLEGAL_STATE;
return nullptr;
}
bool DwarfSection::Step(uint64_t pc, Regs* regs, Memory* process_memory, bool* finished) {
last_error_.code = DWARF_ERROR_NONE;
const DwarfFde* fde = GetFdeFromPc(pc);
if (fde == nullptr || fde->cie == nullptr) {
last_error_.code = DWARF_ERROR_ILLEGAL_STATE;
return false;
}
// Now get the location information for this pc.
dwarf_loc_regs_t loc_regs;
if (!GetCfaLocationInfo(pc, fde, &loc_regs)) {
return false;
}
// Now eval the actual registers.
return Eval(fde->cie, process_memory, loc_regs, regs, finished);
}
template <typename AddressType>
bool DwarfSectionImpl<AddressType>::EvalExpression(const DwarfLocation& loc, Memory* regular_memory,
AddressType* value,
RegsInfo<AddressType>* regs_info,
bool* is_dex_pc) {
DwarfOp<AddressType> op(&memory_, regular_memory);
op.set_regs_info(regs_info);
// Need to evaluate the op data.
uint64_t end = loc.values[1];
uint64_t start = end - loc.values[0];
if (!op.Eval(start, end)) {
last_error_ = op.last_error();
return false;
}
if (op.StackSize() == 0) {
last_error_.code = DWARF_ERROR_ILLEGAL_STATE;
return false;
}
// We don't support an expression that evaluates to a register number.
if (op.is_register()) {
last_error_.code = DWARF_ERROR_NOT_IMPLEMENTED;
return false;
}
*value = op.StackAt(0);
if (is_dex_pc != nullptr && op.dex_pc_set()) {
*is_dex_pc = true;
}
return true;
}
template <typename AddressType>
struct EvalInfo {
const dwarf_loc_regs_t* loc_regs;
const DwarfCie* cie;
Memory* regular_memory;
AddressType cfa;
bool return_address_undefined = false;
RegsInfo<AddressType> regs_info;
};
template <typename AddressType>
bool DwarfSectionImpl<AddressType>::EvalRegister(const DwarfLocation* loc, uint32_t reg,
AddressType* reg_ptr, void* info) {
EvalInfo<AddressType>* eval_info = reinterpret_cast<EvalInfo<AddressType>*>(info);
Memory* regular_memory = eval_info->regular_memory;
switch (loc->type) {
case DWARF_LOCATION_OFFSET:
if (!regular_memory->ReadFully(eval_info->cfa + loc->values[0], reg_ptr, sizeof(AddressType))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = eval_info->cfa + loc->values[0];
return false;
}
break;
case DWARF_LOCATION_VAL_OFFSET:
*reg_ptr = eval_info->cfa + loc->values[0];
break;
case DWARF_LOCATION_REGISTER: {
uint32_t cur_reg = loc->values[0];
if (cur_reg >= eval_info->regs_info.Total()) {
last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
return false;
}
*reg_ptr = eval_info->regs_info.Get(cur_reg) + loc->values[1];
break;
}
case DWARF_LOCATION_EXPRESSION:
case DWARF_LOCATION_VAL_EXPRESSION: {
AddressType value;
bool is_dex_pc = false;
if (!EvalExpression(*loc, regular_memory, &value, &eval_info->regs_info, &is_dex_pc)) {
return false;
}
if (loc->type == DWARF_LOCATION_EXPRESSION) {
if (!regular_memory->ReadFully(value, reg_ptr, sizeof(AddressType))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = value;
return false;
}
} else {
*reg_ptr = value;
if (is_dex_pc) {
eval_info->regs_info.regs->set_dex_pc(value);
}
}
break;
}
case DWARF_LOCATION_UNDEFINED:
if (reg == eval_info->cie->return_address_register) {
eval_info->return_address_undefined = true;
}
default:
break;
}
return true;
}
template <typename AddressType>
bool DwarfSectionImpl<AddressType>::Eval(const DwarfCie* cie, Memory* regular_memory,
const dwarf_loc_regs_t& loc_regs, Regs* regs,
bool* finished) {
RegsImpl<AddressType>* cur_regs = reinterpret_cast<RegsImpl<AddressType>*>(regs);
if (cie->return_address_register >= cur_regs->total_regs()) {
last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
return false;
}
// Get the cfa value;
auto cfa_entry = loc_regs.find(CFA_REG);
if (cfa_entry == loc_regs.end()) {
last_error_.code = DWARF_ERROR_CFA_NOT_DEFINED;
return false;
}
// Always set the dex pc to zero when evaluating.
cur_regs->set_dex_pc(0);
AddressType prev_cfa = regs->sp();
EvalInfo<AddressType> eval_info{.loc_regs = &loc_regs,
.cie = cie,
.regular_memory = regular_memory,
.regs_info = RegsInfo<AddressType>(cur_regs)};
const DwarfLocation* loc = &cfa_entry->second;
// Only a few location types are valid for the cfa.
switch (loc->type) {
case DWARF_LOCATION_REGISTER:
if (loc->values[0] >= cur_regs->total_regs()) {
last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
return false;
}
// If the stack pointer register is the CFA, and the stack
// pointer register does not have any associated location
// information, use the current cfa value.
if (regs->sp_reg() == loc->values[0] && loc_regs.count(regs->sp_reg()) == 0) {
eval_info.cfa = prev_cfa;
} else {
eval_info.cfa = (*cur_regs)[loc->values[0]];
}
eval_info.cfa += loc->values[1];
break;
case DWARF_LOCATION_EXPRESSION:
case DWARF_LOCATION_VAL_EXPRESSION: {
AddressType value;
if (!EvalExpression(*loc, regular_memory, &value, &eval_info.regs_info, nullptr)) {
return false;
}
if (loc->type == DWARF_LOCATION_EXPRESSION) {
if (!regular_memory->ReadFully(value, &eval_info.cfa, sizeof(AddressType))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = value;
return false;
}
} else {
eval_info.cfa = value;
}
break;
}
default:
last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
return false;
}
for (const auto& entry : loc_regs) {
uint32_t reg = entry.first;
// Already handled the CFA register.
if (reg == CFA_REG) continue;
AddressType* reg_ptr;
if (reg >= cur_regs->total_regs()) {
// Skip this unknown register.
continue;
}
reg_ptr = eval_info.regs_info.Save(reg);
if (!EvalRegister(&entry.second, reg, reg_ptr, &eval_info)) {
return false;
}
}
// Find the return address location.
if (eval_info.return_address_undefined) {
cur_regs->set_pc(0);
} else {
cur_regs->set_pc((*cur_regs)[cie->return_address_register]);
}
// If the pc was set to zero, consider this the final frame.
*finished = (cur_regs->pc() == 0) ? true : false;
cur_regs->set_sp(eval_info.cfa);
return true;
}
template <typename AddressType>
const DwarfCie* DwarfSectionImpl<AddressType>::GetCie(uint64_t offset) {
auto cie_entry = cie_entries_.find(offset);
if (cie_entry != cie_entries_.end()) {
return &cie_entry->second;
}
DwarfCie* cie = &cie_entries_[offset];
memory_.set_cur_offset(offset);
if (!FillInCie(cie)) {
// Erase the cached entry.
cie_entries_.erase(offset);
return nullptr;
}
return cie;
}
template <typename AddressType>
bool DwarfSectionImpl<AddressType>::FillInCie(DwarfCie* cie) {
uint32_t length32;
if (!memory_.ReadBytes(&length32, sizeof(length32))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
// Set the default for the lsda encoding.
cie->lsda_encoding = DW_EH_PE_omit;
if (length32 == static_cast<uint32_t>(-1)) {
// 64 bit Cie
uint64_t length64;
if (!memory_.ReadBytes(&length64, sizeof(length64))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
cie->cfa_instructions_end = memory_.cur_offset() + length64;
cie->fde_address_encoding = DW_EH_PE_sdata8;
uint64_t cie_id;
if (!memory_.ReadBytes(&cie_id, sizeof(cie_id))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (cie_id != cie64_value_) {
// This is not a Cie, something has gone horribly wrong.
last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
return false;
}
} else {
// 32 bit Cie
cie->cfa_instructions_end = memory_.cur_offset() + length32;
cie->fde_address_encoding = DW_EH_PE_sdata4;
uint32_t cie_id;
if (!memory_.ReadBytes(&cie_id, sizeof(cie_id))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (cie_id != cie32_value_) {
// This is not a Cie, something has gone horribly wrong.
last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
return false;
}
}
if (!memory_.ReadBytes(&cie->version, sizeof(cie->version))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (cie->version != 1 && cie->version != 3 && cie->version != 4) {
// Unrecognized version.
last_error_.code = DWARF_ERROR_UNSUPPORTED_VERSION;
return false;
}
// Read the augmentation string.
char aug_value;
do {
if (!memory_.ReadBytes(&aug_value, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
cie->augmentation_string.push_back(aug_value);
} while (aug_value != '\0');
if (cie->version == 4) {
// Skip the Address Size field since we only use it for validation.
memory_.set_cur_offset(memory_.cur_offset() + 1);
// Segment Size
if (!memory_.ReadBytes(&cie->segment_size, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
}
// Code Alignment Factor
if (!memory_.ReadULEB128(&cie->code_alignment_factor)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
// Data Alignment Factor
if (!memory_.ReadSLEB128(&cie->data_alignment_factor)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (cie->version == 1) {
// Return Address is a single byte.
uint8_t return_address_register;
if (!memory_.ReadBytes(&return_address_register, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
cie->return_address_register = return_address_register;
} else if (!memory_.ReadULEB128(&cie->return_address_register)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (cie->augmentation_string[0] != 'z') {
cie->cfa_instructions_offset = memory_.cur_offset();
return true;
}
uint64_t aug_length;
if (!memory_.ReadULEB128(&aug_length)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
cie->cfa_instructions_offset = memory_.cur_offset() + aug_length;
for (size_t i = 1; i < cie->augmentation_string.size(); i++) {
switch (cie->augmentation_string[i]) {
case 'L':
if (!memory_.ReadBytes(&cie->lsda_encoding, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
break;
case 'P': {
uint8_t encoding;
if (!memory_.ReadBytes(&encoding, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (!memory_.ReadEncodedValue<AddressType>(encoding, &cie->personality_handler)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
} break;
case 'R':
if (!memory_.ReadBytes(&cie->fde_address_encoding, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
break;
}
}
return true;
}
template <typename AddressType>
const DwarfFde* DwarfSectionImpl<AddressType>::GetFdeFromOffset(uint64_t offset) {
auto fde_entry = fde_entries_.find(offset);
if (fde_entry != fde_entries_.end()) {
return &fde_entry->second;
}
DwarfFde* fde = &fde_entries_[offset];
memory_.set_cur_offset(offset);
if (!FillInFde(fde)) {
fde_entries_.erase(offset);
return nullptr;
}
return fde;
}
template <typename AddressType>
bool DwarfSectionImpl<AddressType>::FillInFde(DwarfFde* fde) {
uint32_t length32;
if (!memory_.ReadBytes(&length32, sizeof(length32))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (length32 == static_cast<uint32_t>(-1)) {
// 64 bit Fde.
uint64_t length64;
if (!memory_.ReadBytes(&length64, sizeof(length64))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
fde->cfa_instructions_end = memory_.cur_offset() + length64;
uint64_t value64;
if (!memory_.ReadBytes(&value64, sizeof(value64))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (value64 == cie64_value_) {
// This is a Cie, this means something has gone wrong.
last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
return false;
}
// Get the Cie pointer, which is necessary to properly read the rest of
// of the Fde information.
fde->cie_offset = GetCieOffsetFromFde64(value64);
} else {
// 32 bit Fde.
fde->cfa_instructions_end = memory_.cur_offset() + length32;
uint32_t value32;
if (!memory_.ReadBytes(&value32, sizeof(value32))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (value32 == cie32_value_) {
// This is a Cie, this means something has gone wrong.
last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
return false;
}
// Get the Cie pointer, which is necessary to properly read the rest of
// of the Fde information.
fde->cie_offset = GetCieOffsetFromFde32(value32);
}
uint64_t cur_offset = memory_.cur_offset();
const DwarfCie* cie = GetCie(fde->cie_offset);
if (cie == nullptr) {
return false;
}
fde->cie = cie;
if (cie->segment_size != 0) {
// Skip over the segment selector for now.
cur_offset += cie->segment_size;
}
memory_.set_cur_offset(cur_offset);
if (!memory_.ReadEncodedValue<AddressType>(cie->fde_address_encoding & 0xf, &fde->pc_start)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
fde->pc_start = AdjustPcFromFde(fde->pc_start);
if (!memory_.ReadEncodedValue<AddressType>(cie->fde_address_encoding & 0xf, &fde->pc_end)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
fde->pc_end += fde->pc_start;
if (cie->augmentation_string.size() > 0 && cie->augmentation_string[0] == 'z') {
// Augmentation Size
uint64_t aug_length;
if (!memory_.ReadULEB128(&aug_length)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
uint64_t cur_offset = memory_.cur_offset();
if (!memory_.ReadEncodedValue<AddressType>(cie->lsda_encoding, &fde->lsda_address)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
// Set our position to after all of the augmentation data.
memory_.set_cur_offset(cur_offset + aug_length);
}
fde->cfa_instructions_offset = memory_.cur_offset();
return true;
}
template <typename AddressType>
bool DwarfSectionImpl<AddressType>::GetCfaLocationInfo(uint64_t pc, const DwarfFde* fde,
dwarf_loc_regs_t* loc_regs) {
DwarfCfa<AddressType> cfa(&memory_, fde);
// Look for the cached copy of the cie data.
auto reg_entry = cie_loc_regs_.find(fde->cie_offset);
if (reg_entry == cie_loc_regs_.end()) {
if (!cfa.GetLocationInfo(pc, fde->cie->cfa_instructions_offset, fde->cie->cfa_instructions_end,
loc_regs)) {
last_error_ = cfa.last_error();
return false;
}
cie_loc_regs_[fde->cie_offset] = *loc_regs;
}
cfa.set_cie_loc_regs(&cie_loc_regs_[fde->cie_offset]);
if (!cfa.GetLocationInfo(pc, fde->cfa_instructions_offset, fde->cfa_instructions_end, loc_regs)) {
last_error_ = cfa.last_error();
return false;
}
return true;
}
template <typename AddressType>
bool DwarfSectionImpl<AddressType>::Log(uint8_t indent, uint64_t pc, uint64_t load_bias,
const DwarfFde* fde) {
DwarfCfa<AddressType> cfa(&memory_, fde);
// Always print the cie information.
const DwarfCie* cie = fde->cie;
if (!cfa.Log(indent, pc, load_bias, cie->cfa_instructions_offset, cie->cfa_instructions_end)) {
last_error_ = cfa.last_error();
return false;
}
if (!cfa.Log(indent, pc, load_bias, fde->cfa_instructions_offset, fde->cfa_instructions_end)) {
last_error_ = cfa.last_error();
return false;
}
return true;
}
template <typename AddressType>
bool DwarfSectionImpl<AddressType>::Init(uint64_t offset, uint64_t size) {
entries_offset_ = offset;
entries_end_ = offset + size;
memory_.clear_func_offset();
memory_.clear_text_offset();
memory_.set_data_offset(offset);
memory_.set_cur_offset(offset);
memory_.set_pc_offset(offset);
return CreateSortedFdeList();
}
template <typename AddressType>
bool DwarfSectionImpl<AddressType>::GetCieInfo(uint8_t* segment_size, uint8_t* encoding) {
uint8_t version;
if (!memory_.ReadBytes(&version, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
// Read the augmentation string.
std::vector<char> aug_string;
char aug_value;
bool get_encoding = false;
do {
if (!memory_.ReadBytes(&aug_value, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (aug_value == 'R') {
get_encoding = true;
}
aug_string.push_back(aug_value);
} while (aug_value != '\0');
if (version == 4) {
// Skip the Address Size field.
memory_.set_cur_offset(memory_.cur_offset() + 1);
// Read the segment size.
if (!memory_.ReadBytes(segment_size, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
} else {
*segment_size = 0;
}
if (aug_string[0] != 'z' || !get_encoding) {
// No encoding
return true;
}
// Skip code alignment factor
uint8_t value;
do {
if (!memory_.ReadBytes(&value, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
} while (value & 0x80);
// Skip data alignment factor
do {
if (!memory_.ReadBytes(&value, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
} while (value & 0x80);
if (version == 1) {
// Skip return address register.
memory_.set_cur_offset(memory_.cur_offset() + 1);
} else {
// Skip return address register.
do {
if (!memory_.ReadBytes(&value, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
} while (value & 0x80);
}
// Skip the augmentation length.
do {
if (!memory_.ReadBytes(&value, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
} while (value & 0x80);
for (size_t i = 1; i < aug_string.size(); i++) {
if (aug_string[i] == 'R') {
if (!memory_.ReadBytes(encoding, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
// Got the encoding, that's all we are looking for.
return true;
} else if (aug_string[i] == 'L') {
memory_.set_cur_offset(memory_.cur_offset() + 1);
} else if (aug_string[i] == 'P') {
uint8_t encoding;
if (!memory_.ReadBytes(&encoding, 1)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
uint64_t value;
if (!memory_.template ReadEncodedValue<AddressType>(encoding, &value)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
}
}
// It should be impossible to get here.
abort();
}
template <typename AddressType>
bool DwarfSectionImpl<AddressType>::AddFdeInfo(uint64_t entry_offset, uint8_t segment_size,
uint8_t encoding) {
if (segment_size != 0) {
memory_.set_cur_offset(memory_.cur_offset() + 1);
}
uint64_t start;
if (!memory_.template ReadEncodedValue<AddressType>(encoding & 0xf, &start)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
start = AdjustPcFromFde(start);
uint64_t length;
if (!memory_.template ReadEncodedValue<AddressType>(encoding & 0xf, &length)) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (length != 0) {
fdes_.emplace_back(entry_offset, start, length);
}
return true;
}
template <typename AddressType>
bool DwarfSectionImpl<AddressType>::CreateSortedFdeList() {
memory_.set_cur_offset(entries_offset_);
// Loop through all of the entries and read just enough to create
// a sorted list of pcs.
// This code assumes that first comes the cie, then the fdes that
// it applies to.
uint64_t cie_offset = 0;
uint8_t address_encoding;
uint8_t segment_size;
while (memory_.cur_offset() < entries_end_) {
uint64_t cur_entry_offset = memory_.cur_offset();
// Figure out the entry length and type.
uint32_t value32;
if (!memory_.ReadBytes(&value32, sizeof(value32))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
uint64_t next_entry_offset;
if (value32 == static_cast<uint32_t>(-1)) {
uint64_t value64;
if (!memory_.ReadBytes(&value64, sizeof(value64))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
next_entry_offset = memory_.cur_offset() + value64;
// Read the Cie Id of a Cie or the pointer of the Fde.
if (!memory_.ReadBytes(&value64, sizeof(value64))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (value64 == cie64_value_) {
// Cie 64 bit
address_encoding = DW_EH_PE_sdata8;
if (!GetCieInfo(&segment_size, &address_encoding)) {
return false;
}
cie_offset = cur_entry_offset;
} else {
uint64_t last_cie_offset = GetCieOffsetFromFde64(value64);
if (last_cie_offset != cie_offset) {
// This means that this Fde is not following the Cie.
last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
return false;
}
// Fde 64 bit
if (!AddFdeInfo(cur_entry_offset, segment_size, address_encoding)) {
return false;
}
}
} else {
next_entry_offset = memory_.cur_offset() + value32;
// Read the Cie Id of a Cie or the pointer of the Fde.
if (!memory_.ReadBytes(&value32, sizeof(value32))) {
last_error_.code = DWARF_ERROR_MEMORY_INVALID;
last_error_.address = memory_.cur_offset();
return false;
}
if (value32 == cie32_value_) {
// Cie 32 bit
address_encoding = DW_EH_PE_sdata4;
if (!GetCieInfo(&segment_size, &address_encoding)) {
return false;
}
cie_offset = cur_entry_offset;
} else {
uint64_t last_cie_offset = GetCieOffsetFromFde32(value32);
if (last_cie_offset != cie_offset) {
// This means that this Fde is not following the Cie.
last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
return false;
}
// Fde 32 bit
if (!AddFdeInfo(cur_entry_offset, segment_size, address_encoding)) {
return false;
}
}
}
if (next_entry_offset < memory_.cur_offset()) {
// Simply consider the processing done in this case.
break;
}
memory_.set_cur_offset(next_entry_offset);
}
// Sort the entries.
std::sort(fdes_.begin(), fdes_.end(), [](const FdeInfo& a, const FdeInfo& b) {
if (a.start == b.start) return a.end < b.end;
return a.start < b.start;
});
fde_count_ = fdes_.size();
return true;
}
template <typename AddressType>
bool DwarfSectionImpl<AddressType>::GetFdeOffsetFromPc(uint64_t pc, uint64_t* fde_offset) {
if (fde_count_ == 0) {
return false;
}
size_t first = 0;
size_t last = fde_count_;
while (first < last) {
size_t current = (first + last) / 2;
const FdeInfo* info = &fdes_[current];
if (pc >= info->start && pc <= info->end) {
*fde_offset = info->offset;
return true;
}
if (pc < info->start) {
last = current;
} else {
first = current + 1;
}
}
return false;
}
template <typename AddressType>
const DwarfFde* DwarfSectionImpl<AddressType>::GetFdeFromIndex(size_t index) {
if (index >= fdes_.size()) {
return nullptr;
}
return this->GetFdeFromOffset(fdes_[index].offset);
}
// Explicitly instantiate DwarfSectionImpl
template class DwarfSectionImpl<uint32_t>;
template class DwarfSectionImpl<uint64_t>;
// Explicitly instantiate DwarfDebugFrame
template class DwarfDebugFrame<uint32_t>;
template class DwarfDebugFrame<uint64_t>;
// Explicitly instantiate DwarfEhFrame
template class DwarfEhFrame<uint32_t>;
template class DwarfEhFrame<uint64_t>;
} // namespace unwindstack
Reference in a new issue View git blame Copy permalink