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Diffstat (limited to 'contrib/llvm-project/lldb/source/Plugins/InstrumentationRuntime/UBSan/InstrumentationRuntimeUBSan.cpp')
| -rw-r--r-- | contrib/llvm-project/lldb/source/Plugins/InstrumentationRuntime/UBSan/InstrumentationRuntimeUBSan.cpp | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/contrib/llvm-project/lldb/source/Plugins/InstrumentationRuntime/UBSan/InstrumentationRuntimeUBSan.cpp b/contrib/llvm-project/lldb/source/Plugins/InstrumentationRuntime/UBSan/InstrumentationRuntimeUBSan.cpp new file mode 100644 index 000000000000..1c58922e8d36 --- /dev/null +++ b/contrib/llvm-project/lldb/source/Plugins/InstrumentationRuntime/UBSan/InstrumentationRuntimeUBSan.cpp @@ -0,0 +1,340 @@ +//===-- InstrumentationRuntimeUBSan.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 "InstrumentationRuntimeUBSan.h" + +#include "Plugins/Process/Utility/HistoryThread.h" +#include "lldb/Breakpoint/StoppointCallbackContext.h" +#include "lldb/Core/Debugger.h" +#include "lldb/Core/Module.h" +#include "lldb/Core/PluginInterface.h" +#include "lldb/Core/PluginManager.h" +#include "lldb/Core/ValueObject.h" +#include "lldb/Expression/UserExpression.h" +#include "lldb/Host/StreamFile.h" +#include "lldb/Interpreter/CommandReturnObject.h" +#include "lldb/Symbol/Symbol.h" +#include "lldb/Symbol/SymbolContext.h" +#include "lldb/Symbol/Variable.h" +#include "lldb/Symbol/VariableList.h" +#include "lldb/Target/InstrumentationRuntimeStopInfo.h" +#include "lldb/Target/SectionLoadList.h" +#include "lldb/Target/StopInfo.h" +#include "lldb/Target/Target.h" +#include "lldb/Target/Thread.h" +#include "lldb/Utility/RegularExpression.h" +#include "lldb/Utility/Stream.h" +#include <cctype> + +#include <memory> + +using namespace lldb; +using namespace lldb_private; + +LLDB_PLUGIN_DEFINE(InstrumentationRuntimeUBSan) + +InstrumentationRuntimeUBSan::~InstrumentationRuntimeUBSan() { Deactivate(); } + +lldb::InstrumentationRuntimeSP +InstrumentationRuntimeUBSan::CreateInstance(const lldb::ProcessSP &process_sp) { + return InstrumentationRuntimeSP(new InstrumentationRuntimeUBSan(process_sp)); +} + +void InstrumentationRuntimeUBSan::Initialize() { + PluginManager::RegisterPlugin( + GetPluginNameStatic(), + "UndefinedBehaviorSanitizer instrumentation runtime plugin.", + CreateInstance, GetTypeStatic); +} + +void InstrumentationRuntimeUBSan::Terminate() { + PluginManager::UnregisterPlugin(CreateInstance); +} + +lldb::InstrumentationRuntimeType InstrumentationRuntimeUBSan::GetTypeStatic() { + return eInstrumentationRuntimeTypeUndefinedBehaviorSanitizer; +} + +static const char *ub_sanitizer_retrieve_report_data_prefix = R"( +extern "C" { +void +__ubsan_get_current_report_data(const char **OutIssueKind, + const char **OutMessage, const char **OutFilename, unsigned *OutLine, + unsigned *OutCol, char **OutMemoryAddr); +} +)"; + +static const char *ub_sanitizer_retrieve_report_data_command = R"( +struct { + const char *issue_kind; + const char *message; + const char *filename; + unsigned line; + unsigned col; + char *memory_addr; +} t; + +__ubsan_get_current_report_data(&t.issue_kind, &t.message, &t.filename, &t.line, + &t.col, &t.memory_addr); +t; +)"; + +static addr_t RetrieveUnsigned(ValueObjectSP return_value_sp, + ProcessSP process_sp, + const std::string &expression_path) { + return return_value_sp->GetValueForExpressionPath(expression_path.c_str()) + ->GetValueAsUnsigned(0); +} + +static std::string RetrieveString(ValueObjectSP return_value_sp, + ProcessSP process_sp, + const std::string &expression_path) { + addr_t ptr = RetrieveUnsigned(return_value_sp, process_sp, expression_path); + std::string str; + Status error; + process_sp->ReadCStringFromMemory(ptr, str, error); + return str; +} + +StructuredData::ObjectSP InstrumentationRuntimeUBSan::RetrieveReportData( + ExecutionContextRef exe_ctx_ref) { + ProcessSP process_sp = GetProcessSP(); + if (!process_sp) + return StructuredData::ObjectSP(); + + ThreadSP thread_sp = exe_ctx_ref.GetThreadSP(); + StackFrameSP frame_sp = + thread_sp->GetSelectedFrame(DoNoSelectMostRelevantFrame); + ModuleSP runtime_module_sp = GetRuntimeModuleSP(); + Target &target = process_sp->GetTarget(); + + if (!frame_sp) + return StructuredData::ObjectSP(); + + StreamFileSP Stream = target.GetDebugger().GetOutputStreamSP(); + + EvaluateExpressionOptions options; + options.SetUnwindOnError(true); + options.SetTryAllThreads(true); + options.SetStopOthers(true); + options.SetIgnoreBreakpoints(true); + options.SetTimeout(process_sp->GetUtilityExpressionTimeout()); + options.SetPrefix(ub_sanitizer_retrieve_report_data_prefix); + options.SetAutoApplyFixIts(false); + options.SetLanguage(eLanguageTypeObjC_plus_plus); + + ValueObjectSP main_value; + ExecutionContext exe_ctx; + Status eval_error; + frame_sp->CalculateExecutionContext(exe_ctx); + ExpressionResults result = UserExpression::Evaluate( + exe_ctx, options, ub_sanitizer_retrieve_report_data_command, "", + main_value, eval_error); + if (result != eExpressionCompleted) { + StreamString ss; + ss << "cannot evaluate UndefinedBehaviorSanitizer expression:\n"; + ss << eval_error.AsCString(); + Debugger::ReportWarning(ss.GetString().str(), + process_sp->GetTarget().GetDebugger().GetID()); + return StructuredData::ObjectSP(); + } + + // Gather the PCs of the user frames in the backtrace. + StructuredData::Array *trace = new StructuredData::Array(); + auto trace_sp = StructuredData::ObjectSP(trace); + for (unsigned I = 0; I < thread_sp->GetStackFrameCount(); ++I) { + const Address FCA = thread_sp->GetStackFrameAtIndex(I) + ->GetFrameCodeAddressForSymbolication(); + if (FCA.GetModule() == runtime_module_sp) // Skip PCs from the runtime. + continue; + + lldb::addr_t PC = FCA.GetLoadAddress(&target); + trace->AddIntegerItem(PC); + } + + std::string IssueKind = RetrieveString(main_value, process_sp, ".issue_kind"); + std::string ErrMessage = RetrieveString(main_value, process_sp, ".message"); + std::string Filename = RetrieveString(main_value, process_sp, ".filename"); + unsigned Line = RetrieveUnsigned(main_value, process_sp, ".line"); + unsigned Col = RetrieveUnsigned(main_value, process_sp, ".col"); + uintptr_t MemoryAddr = + RetrieveUnsigned(main_value, process_sp, ".memory_addr"); + + auto *d = new StructuredData::Dictionary(); + auto dict_sp = StructuredData::ObjectSP(d); + d->AddStringItem("instrumentation_class", "UndefinedBehaviorSanitizer"); + d->AddStringItem("description", IssueKind); + d->AddStringItem("summary", ErrMessage); + d->AddStringItem("filename", Filename); + d->AddIntegerItem("line", Line); + d->AddIntegerItem("col", Col); + d->AddIntegerItem("memory_address", MemoryAddr); + d->AddIntegerItem("tid", thread_sp->GetID()); + d->AddItem("trace", trace_sp); + return dict_sp; +} + +static std::string GetStopReasonDescription(StructuredData::ObjectSP report) { + llvm::StringRef stop_reason_description_ref; + report->GetAsDictionary()->GetValueForKeyAsString( + "description", stop_reason_description_ref); + std::string stop_reason_description = + std::string(stop_reason_description_ref); + + if (!stop_reason_description.size()) { + stop_reason_description = "Undefined behavior detected"; + } else { + stop_reason_description[0] = toupper(stop_reason_description[0]); + for (unsigned I = 1; I < stop_reason_description.size(); ++I) + if (stop_reason_description[I] == '-') + stop_reason_description[I] = ' '; + } + return stop_reason_description; +} + +bool InstrumentationRuntimeUBSan::NotifyBreakpointHit( + void *baton, StoppointCallbackContext *context, user_id_t break_id, + user_id_t break_loc_id) { + assert(baton && "null baton"); + if (!baton) + return false; ///< false => resume execution. + + InstrumentationRuntimeUBSan *const instance = + static_cast<InstrumentationRuntimeUBSan *>(baton); + + ProcessSP process_sp = instance->GetProcessSP(); + ThreadSP thread_sp = context->exe_ctx_ref.GetThreadSP(); + if (!process_sp || !thread_sp || + process_sp != context->exe_ctx_ref.GetProcessSP()) + return false; + + if (process_sp->GetModIDRef().IsLastResumeForUserExpression()) + return false; + + StructuredData::ObjectSP report = + instance->RetrieveReportData(context->exe_ctx_ref); + + if (report) { + thread_sp->SetStopInfo( + InstrumentationRuntimeStopInfo::CreateStopReasonWithInstrumentationData( + *thread_sp, GetStopReasonDescription(report), report)); + return true; + } + + return false; +} + +const RegularExpression & +InstrumentationRuntimeUBSan::GetPatternForRuntimeLibrary() { + static RegularExpression regex(llvm::StringRef("libclang_rt\\.(a|t|ub)san_")); + return regex; +} + +bool InstrumentationRuntimeUBSan::CheckIfRuntimeIsValid( + const lldb::ModuleSP module_sp) { + static ConstString ubsan_test_sym("__ubsan_on_report"); + const Symbol *symbol = module_sp->FindFirstSymbolWithNameAndType( + ubsan_test_sym, lldb::eSymbolTypeAny); + return symbol != nullptr; +} + +// FIXME: Factor out all the logic we have in common with the {a,t}san plugins. +void InstrumentationRuntimeUBSan::Activate() { + if (IsActive()) + return; + + ProcessSP process_sp = GetProcessSP(); + if (!process_sp) + return; + + ModuleSP runtime_module_sp = GetRuntimeModuleSP(); + + ConstString symbol_name("__ubsan_on_report"); + const Symbol *symbol = runtime_module_sp->FindFirstSymbolWithNameAndType( + symbol_name, eSymbolTypeCode); + + if (symbol == nullptr) + return; + + if (!symbol->ValueIsAddress() || !symbol->GetAddressRef().IsValid()) + return; + + Target &target = process_sp->GetTarget(); + addr_t symbol_address = symbol->GetAddressRef().GetOpcodeLoadAddress(&target); + + if (symbol_address == LLDB_INVALID_ADDRESS) + return; + + Breakpoint *breakpoint = + process_sp->GetTarget() + .CreateBreakpoint(symbol_address, /*internal=*/true, + /*hardware=*/false) + .get(); + const bool sync = false; + breakpoint->SetCallback(InstrumentationRuntimeUBSan::NotifyBreakpointHit, + this, sync); + breakpoint->SetBreakpointKind("undefined-behavior-sanitizer-report"); + SetBreakpointID(breakpoint->GetID()); + + SetActive(true); +} + +void InstrumentationRuntimeUBSan::Deactivate() { + SetActive(false); + + auto BID = GetBreakpointID(); + if (BID == LLDB_INVALID_BREAK_ID) + return; + + if (ProcessSP process_sp = GetProcessSP()) { + process_sp->GetTarget().RemoveBreakpointByID(BID); + SetBreakpointID(LLDB_INVALID_BREAK_ID); + } +} + +lldb::ThreadCollectionSP +InstrumentationRuntimeUBSan::GetBacktracesFromExtendedStopInfo( + StructuredData::ObjectSP info) { + ThreadCollectionSP threads; + threads = std::make_shared<ThreadCollection>(); + + ProcessSP process_sp = GetProcessSP(); + + if (info->GetObjectForDotSeparatedPath("instrumentation_class") + ->GetStringValue() != "UndefinedBehaviorSanitizer") + return threads; + + std::vector<lldb::addr_t> PCs; + auto trace = info->GetObjectForDotSeparatedPath("trace")->GetAsArray(); + trace->ForEach([&PCs](StructuredData::Object *PC) -> bool { + PCs.push_back(PC->GetUnsignedIntegerValue()); + return true; + }); + + if (PCs.empty()) + return threads; + + StructuredData::ObjectSP thread_id_obj = + info->GetObjectForDotSeparatedPath("tid"); + tid_t tid = thread_id_obj ? thread_id_obj->GetUnsignedIntegerValue() : 0; + + // We gather symbolication addresses above, so no need for HistoryThread to + // try to infer the call addresses. + bool pcs_are_call_addresses = true; + ThreadSP new_thread_sp = std::make_shared<HistoryThread>( + *process_sp, tid, PCs, pcs_are_call_addresses); + std::string stop_reason_description = GetStopReasonDescription(info); + new_thread_sp->SetName(stop_reason_description.c_str()); + + // Save this in the Process' ExtendedThreadList so a strong pointer retains + // the object + process_sp->GetExtendedThreadList().AddThread(new_thread_sp); + threads->AddThread(new_thread_sp); + + return threads; +} |