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Fix more memory leaks with proper smart pointer usage

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Fix more memory leaks, specifically for Module::Extern and
Module::StackFrameEntry that were outside the Module's AddressRange.

To fix this, and to prevent issues like the one fixed by
79326ebe94
in the future, switched to proper use of std::unique_ptr for Module's
Extern and StackFrameEntry functions. These should enforce ownership
correctly and make the ownership flow much more visible and clear.

Change-Id: I7c943dff3501836a5e303febedc1b312e6f0a1fe
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/4129821
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
This commit is contained in:
Ian Barkley-Yeung 2022-12-29 17:32:09 -08:00
parent d91b6cb75a
commit 1eafed6806
8 changed files with 103 additions and 88 deletions
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7
src/common/dwarf_cfi_to_module.cc
View file

@ -33,7 +33,9 @@
// Implementation of google_breakpad::DwarfCFIToModule.
// See dwarf_cfi_to_module.h for details.
#include <memory>
#include <sstream>
#include <utility>
#include "common/dwarf_cfi_to_module.h"
@ -151,7 +153,7 @@ bool DwarfCFIToModule::Entry(size_t offset, uint64_t address, uint64_t length,
// need to check them here.
// Get ready to collect entries.
entry_ = new Module::StackFrameEntry;
entry_ = std::make_unique<Module::StackFrameEntry>();
entry_->address = address;
entry_->size = length;
entry_offset_ = offset;
@ -258,8 +260,7 @@ bool DwarfCFIToModule::ValExpressionRule(uint64_t address, int reg,
}
bool DwarfCFIToModule::End() {
module_->AddStackFrameEntry(entry_);
entry_ = NULL;
module_->AddStackFrameEntry(std::move(entry_));
return true;
}

7
src/common/dwarf_cfi_to_module.h
View file

@ -43,6 +43,7 @@
#include <set>
#include <string>
#include <memory>
#include <vector>
#include "common/module.h"
@ -131,9 +132,9 @@ class DwarfCFIToModule: public CallFrameInfo::Handler {
DwarfCFIToModule(Module* module, const vector<string>& register_names,
Reporter* reporter)
: module_(module), register_names_(register_names), reporter_(reporter),
entry_(NULL), return_address_(-1), cfa_name_(".cfa"), ra_name_(".ra") {
return_address_(-1), cfa_name_(".cfa"), ra_name_(".ra") {
}
virtual ~DwarfCFIToModule() { delete entry_; }
virtual ~DwarfCFIToModule() = default;
virtual bool Entry(size_t offset, uint64_t address, uint64_t length,
uint8_t version, const string& augmentation,
@ -170,7 +171,7 @@ class DwarfCFIToModule: public CallFrameInfo::Handler {
Reporter* reporter_;
// The current entry we're constructing.
Module::StackFrameEntry* entry_;
std::unique_ptr<Module::StackFrameEntry> entry_;
// The section offset of the current frame description entry, for
// use in error messages.

7
src/common/linux/elf_symbols_to_module.cc
View file

@ -36,6 +36,9 @@
#include <elf.h>
#include <string.h>
#include <memory>
#include <utility>
#include "common/byte_cursor.h"
#include "common/module.h"
@ -156,7 +159,7 @@ bool ELFSymbolsToModule(const uint8_t* symtab_section,
while(!iterator->at_end) {
if (ELF32_ST_TYPE(iterator->info) == STT_FUNC &&
iterator->shndx != SHN_UNDEF) {
Module::Extern* ext = new Module::Extern(iterator->value);
auto ext = std::make_unique<Module::Extern>(iterator->value);
ext->name = SymbolString(iterator->name_offset, strings);
#if !defined(__ANDROID__) // Android NDK doesn't provide abi::__cxa_demangle.
int status = 0;
@ -168,7 +171,7 @@ bool ELFSymbolsToModule(const uint8_t* symtab_section,
free(demangled);
}
#endif
module->AddExtern(ext);
module->AddExtern(std::move(ext));
}
++iterator;
}

45
src/common/module.cc
View file

@ -117,12 +117,6 @@ Module::~Module() {
it != functions_.end(); ++it) {
delete *it;
}
for (vector<StackFrameEntry*>::iterator it = stack_frame_entries_.begin();
it != stack_frame_entries_.end(); ++it) {
delete *it;
}
for (ExternSet::iterator it = externs_.begin(); it != externs_.end(); ++it)
delete *it;
}
void Module::SetLoadAddress(Address address) {
@ -155,12 +149,11 @@ bool Module::AddFunction(Function* function) {
}
if (it_ext != externs_.end()) {
if (enable_multiple_field_) {
Extern* found_ext = *it_ext;
Extern* found_ext = it_ext->get();
// If the PUBLIC is for the same symbol as the FUNC, don't mark multiple.
function->is_multiple |=
found_ext->name != function->name || found_ext->is_multiple;
}
delete *it_ext;
externs_.erase(it_ext);
}
#if _DEBUG
@ -194,27 +187,22 @@ bool Module::AddFunction(Function* function) {
return true;
}
void Module::AddStackFrameEntry(StackFrameEntry* stack_frame_entry) {
void Module::AddStackFrameEntry(std::unique_ptr<StackFrameEntry> stack_frame_entry) {
if (!AddressIsInModule(stack_frame_entry->address)) {
return;
}
stack_frame_entries_.push_back(stack_frame_entry);
stack_frame_entries_.push_back(std::move(stack_frame_entry));
}
void Module::AddExtern(Extern* ext) {
void Module::AddExtern(std::unique_ptr<Extern> ext) {
if (!AddressIsInModule(ext->address)) {
return;
}
std::pair<ExternSet::iterator,bool> ret = externs_.insert(ext);
if (!ret.second) {
if (enable_multiple_field_) {
(*ret.first)->is_multiple = true;
}
// Free the duplicate that was not inserted because this Module
// now owns it.
delete ext;
std::pair<ExternSet::iterator,bool> ret = externs_.emplace(std::move(ext));
if (!ret.second && enable_multiple_field_) {
(*ret.first)->is_multiple = true;
}
}
@ -225,7 +213,11 @@ void Module::GetFunctions(vector<Function*>* vec,
void Module::GetExterns(vector<Extern*>* vec,
vector<Extern*>::iterator i) {
vec->insert(i, externs_.begin(), externs_.end());
auto pos = vec->insert(i, externs_.size(), nullptr);
for (const std::unique_ptr<Extern>& ext : externs_) {
*pos = ext.get();
++pos;
}
}
Module::File* Module::FindFile(const string& name) {
@ -267,7 +259,11 @@ void Module::GetFiles(vector<File*>* vec) {
}
void Module::GetStackFrameEntries(vector<StackFrameEntry*>* vec) const {
*vec = stack_frame_entries_;
vec->clear();
vec->reserve(stack_frame_entries_.size());
for (const auto& ent : stack_frame_entries_) {
vec->push_back(ent.get());
}
}
void Module::AssignSourceIds(
@ -443,7 +439,7 @@ bool Module::Write(std::ostream& stream, SymbolData symbol_data) {
// Write out 'PUBLIC' records.
for (ExternSet::const_iterator extern_it = externs_.begin();
extern_it != externs_.end(); ++extern_it) {
Extern* ext = *extern_it;
Extern* ext = extern_it->get();
stream << "PUBLIC " << (ext->is_multiple ? "m " : "") << hex
<< (ext->address - load_address_) << " 0 " << ext->name << dec
<< "\n";
@ -452,10 +448,9 @@ bool Module::Write(std::ostream& stream, SymbolData symbol_data) {
if (symbol_data & CFI) {
// Write out 'STACK CFI INIT' and 'STACK CFI' records.
vector<StackFrameEntry*>::const_iterator frame_it;
for (frame_it = stack_frame_entries_.begin();
for (auto frame_it = stack_frame_entries_.begin();
frame_it != stack_frame_entries_.end(); ++frame_it) {
StackFrameEntry* entry = *frame_it;
StackFrameEntry* entry = frame_it->get();
stream << "STACK CFI INIT " << hex
<< (entry->address - load_address_) << " "
<< entry->size << " " << dec;

21
src/common/module.h
View file

@ -292,7 +292,18 @@ class Module {
};
struct ExternCompare {
bool operator() (const Extern* lhs, const Extern* rhs) const {
// Defining is_transparent allows
// std::set<std::unique_ptr<Extern>, ExternCompare>::find() to be called
// with an Extern* and have set use the overloads below.
using is_transparent = void;
bool operator() (const std::unique_ptr<Extern>& lhs,
const std::unique_ptr<Extern>& rhs) const {
return lhs->address < rhs->address;
}
bool operator() (const Extern* lhs, const std::unique_ptr<Extern>& rhs) const {
return lhs->address < rhs->address;
}
bool operator() (const std::unique_ptr<Extern>& lhs, const Extern* rhs) const {
return lhs->address < rhs->address;
}
};
@ -340,12 +351,12 @@ class Module {
// Add STACK_FRAME_ENTRY to the module.
// This module owns all StackFrameEntry objects added with this
// function: destroying the module destroys them as well.
void AddStackFrameEntry(StackFrameEntry* stack_frame_entry);
void AddStackFrameEntry(std::unique_ptr<StackFrameEntry> stack_frame_entry);
// Add PUBLIC to the module.
// This module owns all Extern objects added with this function:
// destroying the module destroys them as well.
void AddExtern(Extern* ext);
void AddExtern(std::unique_ptr<Extern> ext);
// If this module has a file named NAME, return a pointer to it. If
// it has none, then create one and return a pointer to the new
@ -465,7 +476,7 @@ class Module {
typedef set<Function*, FunctionCompare> FunctionSet;
// A set containing Extern structures, sorted by address.
typedef set<Extern*, ExternCompare> ExternSet;
typedef set<std::unique_ptr<Extern>, ExternCompare> ExternSet;
// The module owns all the files and functions that have been added
// to it; destroying the module frees the Files and Functions these
@ -477,7 +488,7 @@ class Module {
// The module owns all the call frame info entries that have been
// added to it.
vector<StackFrameEntry*> stack_frame_entries_;
vector<std::unique_ptr<StackFrameEntry>> stack_frame_entries_;
// The module owns all the externs that have been added to it;
// destroying the module frees the Externs these point to.

93
src/common/module_unittest.cc
View file

@ -36,8 +36,10 @@
#include <string.h>
#include <algorithm>
#include <memory>
#include <sstream>
#include <string>
#include <utility>
#include "breakpad_googletest_includes.h"
#include "common/module.h"
@ -137,7 +139,7 @@ TEST(Module, WriteRelativeLoadAddress) {
m.AddFunction(function);
// Some stack information.
Module::StackFrameEntry* entry = new Module::StackFrameEntry();
auto entry = std::make_unique<Module::StackFrameEntry>();
entry->address = 0x30f9e5c83323973dULL;
entry->size = 0x49fc9ca7c7c13dc2ULL;
entry->initial_rules[".cfa"] = "he was a handsome man";
@ -145,7 +147,7 @@ TEST(Module, WriteRelativeLoadAddress) {
entry->rule_changes[0x30f9e5c83323973eULL]["how"] =
"do you like your blueeyed boy";
entry->rule_changes[0x30f9e5c83323973eULL]["Mister"] = "Death";
m.AddStackFrameEntry(entry);
m.AddStackFrameEntry(std::move(entry));
// Set the load address. Doing this after adding all the data to
// the module must work fine.
@ -242,7 +244,7 @@ TEST(Module, WriteNoCFI) {
m.AddFunction(function);
// Some stack information.
Module::StackFrameEntry* entry = new Module::StackFrameEntry();
auto entry = std::make_unique<Module::StackFrameEntry>();
entry->address = 0x30f9e5c83323973dULL;
entry->size = 0x49fc9ca7c7c13dc2ULL;
entry->initial_rules[".cfa"] = "he was a handsome man";
@ -250,7 +252,7 @@ TEST(Module, WriteNoCFI) {
entry->rule_changes[0x30f9e5c83323973eULL]["how"] =
"do you like your blueeyed boy";
entry->rule_changes[0x30f9e5c83323973eULL]["Mister"] = "Death";
m.AddStackFrameEntry(entry);
m.AddStackFrameEntry(std::move(entry));
// Set the load address. Doing this after adding all the data to
// the module must work fine.
@ -321,18 +323,18 @@ TEST(Module, WriteOutOfRangeAddresses) {
// Add three stack frames (one lower, one in, and one higher than the allowed
// address range). Only the middle frame should be captured.
Module::StackFrameEntry* entry1 = new Module::StackFrameEntry();
auto entry1 = std::make_unique<Module::StackFrameEntry>();
entry1->address = 0x1000ULL;
entry1->size = 0x100ULL;
m.AddStackFrameEntry(entry1);
Module::StackFrameEntry* entry2 = new Module::StackFrameEntry();
m.AddStackFrameEntry(std::move(entry1));
auto entry2 = std::make_unique<Module::StackFrameEntry>();
entry2->address = 0x2000ULL;
entry2->size = 0x100ULL;
m.AddStackFrameEntry(entry2);
Module::StackFrameEntry* entry3 = new Module::StackFrameEntry();
m.AddStackFrameEntry(std::move(entry2));
auto entry3 = std::make_unique<Module::StackFrameEntry>();
entry3->address = 0x3000ULL;
entry3->size = 0x100ULL;
m.AddStackFrameEntry(entry3);
m.AddStackFrameEntry(std::move(entry3));
// Add a function outside the allowed range.
Module::File* file = m.FindFile("file_name.cc");
@ -346,9 +348,9 @@ TEST(Module, WriteOutOfRangeAddresses) {
m.AddFunction(function);
// Add an extern outside the allowed range.
Module::Extern* extern1 = new Module::Extern(0x5000ULL);
auto extern1 = std::make_unique<Module::Extern>(0x5000ULL);
extern1->name = "_xyz";
m.AddExtern(extern1);
m.AddExtern(std::move(extern1));
m.Write(s, ALL_SYMBOL_DATA);
@ -357,10 +359,7 @@ TEST(Module, WriteOutOfRangeAddresses) {
s.str().c_str());
// Cleanup - Prevent Memory Leak errors.
delete (extern1);
delete (function);
delete (entry3);
delete (entry1);
}
TEST(Module, ConstructAddFrames) {
@ -368,22 +367,22 @@ TEST(Module, ConstructAddFrames) {
Module m(MODULE_NAME, MODULE_OS, MODULE_ARCH, MODULE_ID);
// First STACK CFI entry, with no initial rules or deltas.
Module::StackFrameEntry* entry1 = new Module::StackFrameEntry();
auto entry1 = std::make_unique<Module::StackFrameEntry>();
entry1->address = 0xddb5f41285aa7757ULL;
entry1->size = 0x1486493370dc5073ULL;
m.AddStackFrameEntry(entry1);
m.AddStackFrameEntry(std::move(entry1));
// Second STACK CFI entry, with initial rules but no deltas.
Module::StackFrameEntry* entry2 = new Module::StackFrameEntry();
auto entry2 = std::make_unique<Module::StackFrameEntry>();
entry2->address = 0x8064f3af5e067e38ULL;
entry2->size = 0x0de2a5ee55509407ULL;
entry2->initial_rules[".cfa"] = "I think that I shall never see";
entry2->initial_rules["stromboli"] = "a poem lovely as a tree";
entry2->initial_rules["cannoli"] = "a tree whose hungry mouth is prest";
m.AddStackFrameEntry(entry2);
m.AddStackFrameEntry(std::move(entry2));
// Third STACK CFI entry, with initial rules and deltas.
Module::StackFrameEntry* entry3 = new Module::StackFrameEntry();
auto entry3 = std::make_unique<Module::StackFrameEntry>();
entry3->address = 0x5e8d0db0a7075c6cULL;
entry3->size = 0x1c7edb12a7aea229ULL;
entry3->initial_rules[".cfa"] = "Whose woods are these";
@ -395,7 +394,7 @@ TEST(Module, ConstructAddFrames) {
"his house is in";
entry3->rule_changes[0x36682fad3763ffffULL][".cfa"] =
"I think I know";
m.AddStackFrameEntry(entry3);
m.AddStackFrameEntry(std::move(entry3));
// Check that Write writes STACK CFI records properly.
m.Write(s, ALL_SYMBOL_DATA);
@ -541,13 +540,13 @@ TEST(Module, ConstructExterns) {
Module m(MODULE_NAME, MODULE_OS, MODULE_ARCH, MODULE_ID);
// Two externs.
Module::Extern* extern1 = new Module::Extern(0xffff);
auto extern1 = std::make_unique<Module::Extern>(0xffff);
extern1->name = "_abc";
Module::Extern* extern2 = new Module::Extern(0xaaaa);
auto extern2 = std::make_unique<Module::Extern>(0xaaaa);
extern2->name = "_xyz";
m.AddExtern(extern1);
m.AddExtern(extern2);
m.AddExtern(std::move(extern1));
m.AddExtern(std::move(extern2));
m.Write(s, ALL_SYMBOL_DATA);
string contents = s.str();
@ -566,13 +565,13 @@ TEST(Module, ConstructDuplicateExterns) {
Module m(MODULE_NAME, MODULE_OS, MODULE_ARCH, MODULE_ID);
// Two externs.
Module::Extern* extern1 = new Module::Extern(0xffff);
auto extern1 = std::make_unique<Module::Extern>(0xffff);
extern1->name = "_xyz";
Module::Extern* extern2 = new Module::Extern(0xffff);
auto extern2 = std::make_unique<Module::Extern>(0xffff);
extern2->name = "_abc";
m.AddExtern(extern1);
m.AddExtern(extern2);
m.AddExtern(std::move(extern1));
m.AddExtern(std::move(extern2));
m.Write(s, ALL_SYMBOL_DATA);
string contents = s.str();
@ -589,13 +588,13 @@ TEST(Module, ConstructDuplicateExternsMultiple) {
Module m(MODULE_NAME, MODULE_OS, MODULE_ARCH, MODULE_ID, "", true);
// Two externs.
Module::Extern* extern1 = new Module::Extern(0xffff);
auto extern1 = std::make_unique<Module::Extern>(0xffff);
extern1->name = "_xyz";
Module::Extern* extern2 = new Module::Extern(0xffff);
auto extern2 = std::make_unique<Module::Extern>(0xffff);
extern2->name = "_abc";
m.AddExtern(extern1);
m.AddExtern(extern2);
m.AddExtern(std::move(extern1));
m.AddExtern(std::move(extern2));
m.Write(s, ALL_SYMBOL_DATA);
string contents = s.str();
@ -613,13 +612,13 @@ TEST(Module, ConstructFunctionsAndExternsWithSameAddress) {
Module m(MODULE_NAME, MODULE_OS, MODULE_ARCH, MODULE_ID);
// Two externs.
Module::Extern* extern1 = new Module::Extern(0xabc0);
auto extern1 = std::make_unique<Module::Extern>(0xabc0);
extern1->name = "abc";
Module::Extern* extern2 = new Module::Extern(0xfff0);
auto extern2 = std::make_unique<Module::Extern>(0xfff0);
extern2->name = "xyz";
m.AddExtern(extern1);
m.AddExtern(extern2);
m.AddExtern(std::move(extern1));
m.AddExtern(std::move(extern2));
Module::Function* function = new Module::Function("_xyz", 0xfff0);
Module::Range range(0xfff0, 0x10);
@ -644,13 +643,13 @@ TEST(Module, ConstructFunctionsAndExternsWithSameAddressMultiple) {
Module m(MODULE_NAME, MODULE_OS, MODULE_ARCH, MODULE_ID, "", true);
// Two externs.
Module::Extern* extern1 = new Module::Extern(0xabc0);
auto extern1 = std::make_unique<Module::Extern>(0xabc0);
extern1->name = "abc";
Module::Extern* extern2 = new Module::Extern(0xfff0);
auto extern2 = std::make_unique<Module::Extern>(0xfff0);
extern2->name = "xyz";
m.AddExtern(extern1);
m.AddExtern(extern2);
m.AddExtern(std::move(extern1));
m.AddExtern(std::move(extern2));
Module::Function* function = new Module::Function("_xyz", 0xfff0);
Module::Range range(0xfff0, 0x10);
@ -676,17 +675,17 @@ TEST(Module, ConstructFunctionsAndThumbExternsWithSameAddress) {
Module m(MODULE_NAME, MODULE_OS, "arm", MODULE_ID);
// Two THUMB externs.
Module::Extern* thumb_extern1 = new Module::Extern(0xabc1);
auto thumb_extern1 = std::make_unique<Module::Extern>(0xabc1);
thumb_extern1->name = "thumb_abc";
Module::Extern* thumb_extern2 = new Module::Extern(0xfff1);
auto thumb_extern2 = std::make_unique<Module::Extern>(0xfff1);
thumb_extern2->name = "thumb_xyz";
Module::Extern* arm_extern1 = new Module::Extern(0xcc00);
auto arm_extern1 = std::make_unique<Module::Extern>(0xcc00);
arm_extern1->name = "arm_func";
m.AddExtern(thumb_extern1);
m.AddExtern(thumb_extern2);
m.AddExtern(arm_extern1);
m.AddExtern(std::move(thumb_extern1));
m.AddExtern(std::move(thumb_extern2));
m.AddExtern(std::move(arm_extern1));
// The corresponding function from the DWARF debug data have the actual
// address.

6
src/common/stabs_to_module.cc
View file

@ -36,6 +36,8 @@
#include <stdio.h>
#include <algorithm>
#include <memory>
#include <utility>
#include "common/stabs_to_module.h"
#include "common/using_std_string.h"
@ -132,7 +134,7 @@ bool StabsToModule::Line(uint64_t address, const char *name, int number) {
}
bool StabsToModule::Extern(const string& name, uint64_t address) {
Module::Extern *ext = new Module::Extern(address);
auto ext = std::make_unique<Module::Extern>(address);
// Older libstdc++ demangle implementations can crash on unexpected
// input, so be careful about what gets passed in.
if (name.compare(0, 3, "__Z") == 0) {
@ -142,7 +144,7 @@ bool StabsToModule::Extern(const string& name, uint64_t address) {
} else {
ext->name = name;
}
module_->AddExtern(ext);
module_->AddExtern(std::move(ext));
return true;
}

5
src/tools/mac/dump_syms/dump_syms_tool.cc
View file

@ -36,6 +36,8 @@
#include <algorithm>
#include <iostream>
#include <memory>
#include <utility>
#include <vector>
#include "common/mac/dump_syms.h"
@ -108,7 +110,8 @@ static void CopyCFIDataBetweenModules(Module* to_module,
// If the entry does not overlap, then it is safe to copy to |to_module|.
if (to_it == to_data.end() || (from_entry->address < (*to_it)->address &&
from_entry_end < (*to_it)->address)) {
to_module->AddStackFrameEntry(new Module::StackFrameEntry(*from_entry));
to_module->AddStackFrameEntry(
std::make_unique<Module::StackFrameEntry>(*from_entry));
}
}
}