Jonas Devlieghere c69307e5ee
[lldb] Prevent object file plugins from changing the data buffer
The current design allows that the object file contents could be mapped
by one object file plugin and then used by another. Presumably the idea
here was to avoid mapping the same file twice.

This becomes an issue when one object file plugin wants to map the file
differently from the others. For example, ObjectFileELF needs to map its
memory as writable while others likeObjectFileMachO needs it to be
mapped read-only.

This patch prevents plugins from changing the buffer by passing them is
by value rather than by reference.

Differential revision: https://reviews.llvm.org/D122944
2022-04-04 09:24:24 -07:00

193 lines
6.1 KiB
C++

//===-- ObjectFilePDB.cpp -------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "ObjectFilePDB.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/ModuleSpec.h"
#include "lldb/Core/PluginManager.h"
#include "lldb/Core/Section.h"
#include "lldb/Utility/StreamString.h"
#include "llvm/BinaryFormat/Magic.h"
#include "llvm/DebugInfo/PDB/Native/DbiStream.h"
#include "llvm/DebugInfo/PDB/Native/InfoStream.h"
#include "llvm/DebugInfo/PDB/Native/NativeSession.h"
#include "llvm/DebugInfo/PDB/Native/PDBFile.h"
#include "llvm/DebugInfo/PDB/PDB.h"
#include "llvm/Support/BinaryByteStream.h"
using namespace lldb;
using namespace lldb_private;
using namespace llvm::pdb;
using namespace llvm::codeview;
LLDB_PLUGIN_DEFINE(ObjectFilePDB)
static UUID GetPDBUUID(InfoStream &IS) {
UUID::CvRecordPdb70 debug_info;
memcpy(&debug_info.Uuid, IS.getGuid().Guid, sizeof(debug_info.Uuid));
debug_info.Age = IS.getAge();
return UUID::fromCvRecord(debug_info);
}
char ObjectFilePDB::ID;
void ObjectFilePDB::Initialize() {
PluginManager::RegisterPlugin(GetPluginNameStatic(),
GetPluginDescriptionStatic(), CreateInstance,
CreateMemoryInstance, GetModuleSpecifications);
}
void ObjectFilePDB::Terminate() {
PluginManager::UnregisterPlugin(CreateInstance);
}
ArchSpec ObjectFilePDB::GetArchitecture() {
auto dbi_stream = m_file_up->getPDBDbiStream();
if (!dbi_stream) {
llvm::consumeError(dbi_stream.takeError());
return ArchSpec();
}
PDB_Machine machine = dbi_stream->getMachineType();
switch (machine) {
default:
break;
case PDB_Machine::Amd64:
case PDB_Machine::x86:
case PDB_Machine::PowerPC:
case PDB_Machine::PowerPCFP:
case PDB_Machine::Arm:
case PDB_Machine::ArmNT:
case PDB_Machine::Thumb:
case PDB_Machine::Arm64:
ArchSpec arch;
arch.SetArchitecture(eArchTypeCOFF, static_cast<int>(machine),
LLDB_INVALID_CPUTYPE);
return arch;
}
return ArchSpec();
}
bool ObjectFilePDB::initPDBFile() {
m_file_up = loadPDBFile(m_file.GetPath(), m_allocator);
if (!m_file_up)
return false;
auto info_stream = m_file_up->getPDBInfoStream();
if (!info_stream) {
llvm::consumeError(info_stream.takeError());
return false;
}
m_uuid = GetPDBUUID(*info_stream);
return true;
}
ObjectFile *
ObjectFilePDB::CreateInstance(const ModuleSP &module_sp, DataBufferSP data_sp,
offset_t data_offset, const FileSpec *file,
offset_t file_offset, offset_t length) {
auto objfile_up = std::make_unique<ObjectFilePDB>(
module_sp, data_sp, data_offset, file, file_offset, length);
if (!objfile_up->initPDBFile())
return nullptr;
return objfile_up.release();
}
ObjectFile *ObjectFilePDB::CreateMemoryInstance(const ModuleSP &module_sp,
DataBufferSP data_sp,
const ProcessSP &process_sp,
addr_t header_addr) {
return nullptr;
}
size_t ObjectFilePDB::GetModuleSpecifications(
const FileSpec &file, DataBufferSP &data_sp, offset_t data_offset,
offset_t file_offset, offset_t length, ModuleSpecList &specs) {
const size_t initial_count = specs.GetSize();
ModuleSpec module_spec(file);
llvm::BumpPtrAllocator allocator;
std::unique_ptr<PDBFile> pdb_file = loadPDBFile(file.GetPath(), allocator);
if (!pdb_file)
return initial_count;
auto info_stream = pdb_file->getPDBInfoStream();
if (!info_stream) {
llvm::consumeError(info_stream.takeError());
return initial_count;
}
auto dbi_stream = pdb_file->getPDBDbiStream();
if (!dbi_stream) {
llvm::consumeError(dbi_stream.takeError());
return initial_count;
}
lldb_private::UUID &uuid = module_spec.GetUUID();
uuid = GetPDBUUID(*info_stream);
ArchSpec &module_arch = module_spec.GetArchitecture();
switch (dbi_stream->getMachineType()) {
case PDB_Machine::Amd64:
module_arch.SetTriple("x86_64-pc-windows");
specs.Append(module_spec);
break;
case PDB_Machine::x86:
module_arch.SetTriple("i386-pc-windows");
specs.Append(module_spec);
module_arch.SetTriple("i686-pc-windows");
specs.Append(module_spec);
break;
case PDB_Machine::ArmNT:
module_arch.SetTriple("armv7-pc-windows");
specs.Append(module_spec);
break;
case PDB_Machine::Arm64:
module_arch.SetTriple("aarch64-pc-windows");
specs.Append(module_spec);
break;
default:
break;
}
return specs.GetSize() - initial_count;
}
ObjectFilePDB::ObjectFilePDB(const ModuleSP &module_sp, DataBufferSP &data_sp,
offset_t data_offset, const FileSpec *file,
offset_t offset, offset_t length)
: ObjectFile(module_sp, file, offset, length, data_sp, data_offset) {}
std::unique_ptr<PDBFile>
ObjectFilePDB::loadPDBFile(std::string PdbPath,
llvm::BumpPtrAllocator &Allocator) {
llvm::file_magic magic;
auto ec = llvm::identify_magic(PdbPath, magic);
if (ec || magic != llvm::file_magic::pdb)
return nullptr;
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> ErrorOrBuffer =
llvm::MemoryBuffer::getFile(PdbPath, /*IsText=*/false,
/*RequiresNullTerminator=*/false);
if (!ErrorOrBuffer)
return nullptr;
std::unique_ptr<llvm::MemoryBuffer> Buffer = std::move(*ErrorOrBuffer);
llvm::StringRef Path = Buffer->getBufferIdentifier();
auto Stream = std::make_unique<llvm::MemoryBufferByteStream>(
std::move(Buffer), llvm::support::little);
auto File = std::make_unique<PDBFile>(Path, std::move(Stream), Allocator);
if (auto EC = File->parseFileHeaders()) {
llvm::consumeError(std::move(EC));
return nullptr;
}
if (auto EC = File->parseStreamData()) {
llvm::consumeError(std::move(EC));
return nullptr;
}
return File;
}