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[SharedCache] Avoid data memory region name conflicts & reduce section naming ones #6454

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[SharedCache] Avoid data memory region name conflicts & reduce section naming ones #6454

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10fb406
[SharedCache] Avoid data memory region name conflicts & reduce sectio…
Mar 23, 2025
4026c0e
[SharedCache] Update the workflow to work with the new section naming…
Mar 23, 2025
8280ac5
Merge branch 'dev' into dsc-fix-region-naming
Mar 23, 2025
1a946b9
[SharedCache] Update the Objective-C processor to work with the new s…
Mar 23, 2025
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24 changes: 12 additions & 12 deletions view/sharedcache/core/ObjC.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1124,13 +1124,13 @@ void DSCObjCProcessor::ApplyMethodTypes(Class& cls)
void DSCObjCProcessor::PostProcessObjCSections(VMReader* reader, std::string baseName)
{
auto ptrSize = m_data->GetAddressSize();
if (auto imageInfo = m_data->GetSectionByName(baseName + "::__objc_imageinfo"))
if (auto imageInfo = m_data->GetSectionByName(baseName + ".__objc_imageinfo"))
{
auto start = imageInfo->GetStart();
auto type = Type::NamedType(m_data, m_typeNames.imageInfo);
m_data->DefineDataVariable(start, type);
}
if (auto selrefs = m_data->GetSectionByName(baseName + "::__objc_selrefs"))
if (auto selrefs = m_data->GetSectionByName(baseName + ".__objc_selrefs"))
{
auto start = selrefs->GetStart();
auto end = selrefs->GetEnd();
Expand All @@ -1153,7 +1153,7 @@ void DSCObjCProcessor::PostProcessObjCSections(VMReader* reader, std::string bas
DefineObjCSymbol(DataSymbol, type, "selRef_" + sel, i, true);
}
}
if (auto superRefs = m_data->GetSectionByName(baseName + "::__objc_classrefs"))
if (auto superRefs = m_data->GetSectionByName(baseName + ".__objc_classrefs"))
{
auto start = superRefs->GetStart();
auto end = superRefs->GetEnd();
Expand All @@ -1171,7 +1171,7 @@ void DSCObjCProcessor::PostProcessObjCSections(VMReader* reader, std::string bas
}
}
}
if (auto superRefs = m_data->GetSectionByName(baseName + "::__objc_superrefs"))
if (auto superRefs = m_data->GetSectionByName(baseName + ".__objc_superrefs"))
{
auto start = superRefs->GetStart();
auto end = superRefs->GetEnd();
Expand All @@ -1189,7 +1189,7 @@ void DSCObjCProcessor::PostProcessObjCSections(VMReader* reader, std::string bas
}
}
}
if (auto protoRefs = m_data->GetSectionByName(baseName + "::__objc_protorefs"))
if (auto protoRefs = m_data->GetSectionByName(baseName + ".__objc_protorefs"))
{
auto start = protoRefs->GetStart();
auto end = protoRefs->GetEnd();
Expand All @@ -1207,7 +1207,7 @@ void DSCObjCProcessor::PostProcessObjCSections(VMReader* reader, std::string bas
}
}
}
if (auto ivars = m_data->GetSectionByName(baseName + "::__objc_ivar"))
if (auto ivars = m_data->GetSectionByName(baseName + ".__objc_ivar"))
{
auto start = ivars->GetStart();
auto end = ivars->GetEnd();
Expand Down Expand Up @@ -1408,23 +1408,23 @@ void DSCObjCProcessor::ProcessObjCData(std::shared_ptr<VM> vm, std::string baseN
m_typeNames.protocol = finalizeStructureBuilder(m_data, protocolBuilder, "objc_protocol_t").first;

m_data->BeginBulkModifySymbols();
if (auto classList = m_data->GetSectionByName(baseName + "::__objc_classlist"))
if (auto classList = m_data->GetSectionByName(baseName + ".__objc_classlist"))
LoadClasses(&reader, classList);
if (auto nonLazyClassList = m_data->GetSectionByName(baseName + "::__objc_nlclslist"))
if (auto nonLazyClassList = m_data->GetSectionByName(baseName + ".__objc_nlclslist"))
LoadClasses(&reader, nonLazyClassList); // See: https://stackoverflow.com/a/15318325

GenerateClassTypes();
for (auto& [_, cls] : m_classes)
ApplyMethodTypes(cls);

if (auto catList = m_data->GetSectionByName(baseName + "::__objc_catlist")) // Do this after loading class type data.
if (auto catList = m_data->GetSectionByName(baseName + ".__objc_catlist")) // Do this after loading class type data.
LoadCategories(&reader, catList);
if (auto nonLazyCatList = m_data->GetSectionByName(baseName + "::__objc_nlcatlist")) // Do this after loading class type data.
if (auto nonLazyCatList = m_data->GetSectionByName(baseName + ".__objc_nlcatlist")) // Do this after loading class type data.
LoadCategories(&reader, nonLazyCatList);
for (auto& [_, cat] : m_categories)
ApplyMethodTypes(cat);

if (auto protoList = m_data->GetSectionByName(baseName + "::__objc_protolist"))
if (auto protoList = m_data->GetSectionByName(baseName + ".__objc_protolist"))
LoadProtocols(&reader, protoList);

PostProcessObjCSections(&reader, baseName);
Expand Down Expand Up @@ -1477,7 +1477,7 @@ void DSCObjCProcessor::ProcessCFStrings(std::shared_ptr<VM> vm, std::string base
m_typeNames.cfStringUTF16 = type.first;

auto reader = VMReader(vm);
if (auto cfstrings = m_data->GetSectionByName(baseName + "::__cfstring"))
if (auto cfstrings = m_data->GetSectionByName(baseName + ".__cfstring"))
{
auto start = cfstrings->GetStart();
auto end = cfstrings->GetEnd();
Expand Down
68 changes: 44 additions & 24 deletions view/sharedcache/core/SharedCache.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1584,6 +1584,11 @@ bool SharedCache::LoadImageContainingAddress(uint64_t address, bool skipObjC)
return false;
}

static std::string GetNameForMemoryDataRegion(const SharedCacheMachOHeader& header, const std::string& regionName)
{
return fmt::format("{}{}", header.installName.substr(0, header.installName.size() - header.identifierPrefix.size()), regionName);
}

bool SharedCache::LoadSectionAtAddress(uint64_t address)
{
std::lock(m_mutex, m_viewSpecificState->viewOperationsThatInfluenceMetadataMutex);
Expand Down Expand Up @@ -1656,7 +1661,7 @@ bool SharedCache::LoadSectionAtAddress(uint64_t address)

auto targetFile = vm->MappingAtAddress(targetSegment->start).first.fileAccessor->lock();
auto buff = reader.ReadBuffer(targetSegment->start, targetSegment->size);
m_dscView->GetMemoryMap()->AddDataMemoryRegion(targetSegment->prettyName, targetSegment->start, buff, targetSegment->flags);
m_dscView->GetMemoryMap()->AddDataMemoryRegion(GetNameForMemoryDataRegion(targetHeader, targetSegment->prettyName), targetSegment->start, buff, targetSegment->flags);

SetMemoryRegionIsLoaded(lock, *targetSegment);

Expand Down Expand Up @@ -1684,22 +1689,34 @@ static void GetObjCSettings(Ref<BinaryView> view, bool* processObjCMetadata, boo
*processObjCMetadata = settings->Get<bool>("loader.dsc.processObjC", view);
}

static void ProcessObjCSectionsForImageWithName(std::string baseName, std::shared_ptr<VM> vm, std::shared_ptr<DSCObjC::DSCObjCProcessor> objc, bool processCFStrings, bool processObjCMetadata, Ref<Logger> logger)
static void ProcessObjCSectionsForMemoryRegion(const MemoryRegion& region, std::shared_ptr<VM> vm, std::shared_ptr<DSCObjC::DSCObjCProcessor> objc, bool processCFStrings, bool processObjCMetadata, Ref<Logger> logger)
{
try
{
if (processObjCMetadata)
objc->ProcessObjCData(vm, baseName);
objc->ProcessObjCData(vm, region.prettyName);
if (processCFStrings)
objc->ProcessCFStrings(vm, baseName);
objc->ProcessCFStrings(vm, region.prettyName);
}
catch (const std::exception& ex)
{
logger->LogWarn("Error processing ObjC data for image %s: %s", baseName.c_str(), ex.what());
logger->LogWarn("Error processing ObjC data for memory region %s: %s", region.prettyName.c_str(), ex.what());
}
catch (...)
{
logger->LogWarn("Error processing ObjC data for image %s", baseName.c_str());
logger->LogWarn("Error processing ObjC data for memory region %s", region.prettyName.c_str());
}
}

void SharedCache::ProcessObjCSectionsForImage(std::lock_guard<std::mutex>& lock, const CacheImage& image, std::shared_ptr<VM> vm, bool processCFStrings, bool processObjCMetadata)
{
const auto objc = std::make_shared<DSCObjC::DSCObjCProcessor>(m_dscView, this, false);
for (auto regionStart : image.regionStarts)
{
const auto& region = m_cacheInfo->memoryRegions.find(regionStart)->second;
if (!MemoryRegionIsLoaded(lock, region))
continue;
ProcessObjCSectionsForMemoryRegion(region, vm, objc, processCFStrings, processObjCMetadata, m_logger);
}
}

Expand All @@ -1712,10 +1729,17 @@ void SharedCache::ProcessObjCSectionsForImageWithInstallName(std::string install
if (!processObjCMetadata && !processCFStrings)
return;

auto objc = std::make_shared<DSCObjC::DSCObjCProcessor>(m_dscView, this, false);
auto vm = GetVMMap();

ProcessObjCSectionsForImageWithName(base_name(installName), vm, objc, processCFStrings, processObjCMetadata, m_logger);
for (const auto& image : this->m_cacheInfo->images)
{
if (image.installName != installName)
continue;

std::lock_guard lock(m_mutex);
ProcessObjCSectionsForImage(lock, image, vm, processCFStrings, processObjCMetadata);
break;
}
}

void SharedCache::ProcessAllObjCSections()
Expand All @@ -1736,18 +1760,9 @@ void SharedCache::ProcessAllObjCSections(std::lock_guard<std::mutex>& lock)
auto objc = std::make_shared<DSCObjC::DSCObjCProcessor>(m_dscView, this, false);
auto vm = GetVMMap();

std::set<uint64_t> processedImageHeaders;
for (auto region : GetMappedRegions())
{
// Don't repeat the same images multiple times
auto header = HeaderForAddress(region->start);
if (!header)
continue;
if (processedImageHeaders.find(header->textBase) != processedImageHeaders.end())
continue;
processedImageHeaders.insert(header->textBase);

ProcessObjCSectionsForImageWithName(header->identifierPrefix, vm, objc, processCFStrings, processObjCMetadata, m_logger);
ProcessObjCSectionsForMemoryRegion(*region, vm, objc, processCFStrings, processObjCMetadata, m_logger);
}
}

Expand Down Expand Up @@ -1818,7 +1833,7 @@ bool SharedCache::LoadImageWithInstallName(std::lock_guard<std::mutex>& lock, st

auto targetFile = vm->MappingAtAddress(region.start).first.fileAccessor->lock();
auto buff = reader.ReadBuffer(region.start, region.size);
m_dscView->GetMemoryMap()->AddDataMemoryRegion(region.prettyName, region.start, buff, region.flags);
m_dscView->GetMemoryMap()->AddDataMemoryRegion(GetNameForMemoryDataRegion(header, region.prettyName), region.start, buff, region.flags);

SetMemoryRegionIsLoaded(lock, region);
regionsToLoad.push_back(&region);
Expand Down Expand Up @@ -1848,7 +1863,7 @@ bool SharedCache::LoadImageWithInstallName(std::lock_guard<std::mutex>& lock, st
bool processObjCMetadata;
GetObjCSettings(m_dscView, &processCFStrings, &processObjCMetadata);

ProcessObjCSectionsForImageWithName(h->identifierPrefix, vm, std::make_shared<DSCObjC::DSCObjCProcessor>(m_dscView, this, false), processCFStrings, processObjCMetadata, m_logger);
ProcessObjCSectionsForImage(lock, *targetImage, vm, processCFStrings, processObjCMetadata);
}

m_dscView->AddAnalysisOption("linearsweep");
Expand Down Expand Up @@ -2250,13 +2265,18 @@ std::optional<SharedCacheMachOHeader> SharedCache::LoadHeaderForAddress(std::sha

for (auto& section : header.sections)
{
char sectionName[17];
char sectionName[sizeof(section.sectname)+1];
memcpy(sectionName, section.sectname, sizeof(section.sectname));
sectionName[16] = 0;
sectionName[sizeof(sectionName)-1] = 0;

char segmentName[sizeof(section.segname)+1];
memcpy(segmentName, section.segname, sizeof(section.segname));
segmentName[sizeof(segmentName)-1] = 0;

if (header.identifierPrefix.empty())
header.sectionNames.push_back(sectionName);
header.sectionNames.push_back(fmt::format("{}.{}", segmentName, sectionName));
else
header.sectionNames.push_back(header.identifierPrefix + "::" + sectionName);
header.sectionNames.push_back(fmt::format("{}::{}.{}", header.identifierPrefix, segmentName, sectionName));
}
}
catch (ReadException&)
Expand Down
1 change: 1 addition & 0 deletions view/sharedcache/core/SharedCache.h
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Original file line number Diff line number Diff line change
Expand Up @@ -647,6 +647,7 @@ namespace SharedCacheCore {
uint64_t stringsOffset, size_t stringsSize, uint64_t nlistEntriesOffset, uint32_t nlistCount, uint32_t nlistStartIndex = 0);
void ApplySymbol(Ref<BinaryView> view, Ref<TypeLibrary> typeLib, Ref<Symbol> symbol);

void ProcessObjCSectionsForImage(std::lock_guard<std::mutex>& lock, const CacheImage& image, std::shared_ptr<VM> vm, bool processCFStrings, bool processObjCMetadata);
void ProcessAllObjCSections(std::lock_guard<std::mutex>&);
bool LoadImageWithInstallName(std::lock_guard<std::mutex>&, std::string installName, bool skipObjC);

Expand Down
13 changes: 7 additions & 6 deletions view/sharedcache/workflow/SharedCacheWorkflow.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -127,7 +127,8 @@ void SharedCacheWorkflow::FixupStubs(Ref<AnalysisContext> ctx)
return;
auto section = bv->GetSectionsAt(funcStart)[0];

auto imageName = section->GetName();
const auto sectionName = section->GetName();
auto imageName = sectionName;
// remove everything after ::
auto pos = imageName.find("::");
if (pos != std::string::npos)
Expand All @@ -152,7 +153,7 @@ void SharedCacheWorkflow::FixupStubs(Ref<AnalysisContext> ctx)
}

// Processor that automatically loads the libObjC image when it encounters a stub (so we can do inlining).
if (workflowState->autoLoadObjCStubRequirements && section->GetName().find("__objc_stubs") != std::string::npos)
if (workflowState->autoLoadObjCStubRequirements && sectionName.find("__objc_stubs") != std::string::npos)
{
auto firstInstruction = mlil->GetInstruction(0);
if (firstInstruction.operation == MLIL_TAILCALL)
Expand Down Expand Up @@ -271,10 +272,10 @@ void SharedCacheWorkflow::FixupStubs(Ref<AnalysisContext> ctx)
return;
}

if (section->GetName().find("::_stubs") != std::string::npos // Branch Islands (iOS 16)
|| section->GetName().find("dyld_shared_cache_branch_islands") != std::string::npos // Branch Islands (iOS 11-?)
|| section->GetName().find("::__stubs") != std::string::npos // Stubs (non arm64e)
|| section->GetName().find("::__auth_stubs") != std::string::npos // Stubs (arm64e)
if (sectionName.find("::_stubs") != std::string::npos // Branch Islands (iOS 16)
|| sectionName.find("dyld_shared_cache_branch_islands") != std::string::npos // Branch Islands (iOS 11-?)
|| sectionName.find(".__stubs") != std::string::npos // Stubs (non arm64e)
|| sectionName.find(".__auth_stubs") != std::string::npos // Stubs (arm64e)
)
{
auto firstInstruction = mlil->GetInstruction(0);
Expand Down