| //===-- sanitizer_symbolizer_report.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 |
| // |
| //===----------------------------------------------------------------------===// |
| /// |
| /// This file is shared between AddressSanitizer and other sanitizer run-time |
| /// libraries and implements symbolized reports related functions. |
| /// |
| //===----------------------------------------------------------------------===// |
| |
| #include "sanitizer_common.h" |
| #include "sanitizer_file.h" |
| #include "sanitizer_flags.h" |
| #include "sanitizer_procmaps.h" |
| #include "sanitizer_report_decorator.h" |
| #include "sanitizer_stacktrace.h" |
| #include "sanitizer_stacktrace_printer.h" |
| #include "sanitizer_symbolizer.h" |
| |
| #if SANITIZER_POSIX |
| # include "sanitizer_posix.h" |
| # include <sys/mman.h> |
| #endif |
| |
| namespace __sanitizer { |
| |
| #if !SANITIZER_GO |
| void ReportErrorSummary(const char *error_type, const AddressInfo &info, |
| const char *alt_tool_name) { |
| if (!common_flags()->print_summary) return; |
| InternalScopedString buff(kMaxSummaryLength); |
| buff.append("%s ", error_type); |
| RenderFrame(&buff, "%L %F", 0, info.address, &info, |
| common_flags()->symbolize_vs_style, |
| common_flags()->strip_path_prefix); |
| ReportErrorSummary(buff.data(), alt_tool_name); |
| } |
| #endif |
| |
| #if !SANITIZER_FUCHSIA |
| |
| bool ReportFile::SupportsColors() { |
| SpinMutexLock l(mu); |
| ReopenIfNecessary(); |
| return SupportsColoredOutput(fd); |
| } |
| |
| static inline bool ReportSupportsColors() { |
| return report_file.SupportsColors(); |
| } |
| |
| #else // SANITIZER_FUCHSIA |
| |
| // Fuchsia's logs always go through post-processing that handles colorization. |
| static inline bool ReportSupportsColors() { return true; } |
| |
| #endif // !SANITIZER_FUCHSIA |
| |
| bool ColorizeReports() { |
| // FIXME: Add proper Windows support to AnsiColorDecorator and re-enable color |
| // printing on Windows. |
| if (SANITIZER_WINDOWS) |
| return false; |
| |
| const char *flag = common_flags()->color; |
| return internal_strcmp(flag, "always") == 0 || |
| (internal_strcmp(flag, "auto") == 0 && ReportSupportsColors()); |
| } |
| |
| void ReportErrorSummary(const char *error_type, const StackTrace *stack, |
| const char *alt_tool_name) { |
| #if !SANITIZER_GO |
| if (!common_flags()->print_summary) |
| return; |
| if (stack->size == 0) { |
| ReportErrorSummary(error_type); |
| return; |
| } |
| // Currently, we include the first stack frame into the report summary. |
| // Maybe sometimes we need to choose another frame (e.g. skip memcpy/etc). |
| uptr pc = StackTrace::GetPreviousInstructionPc(stack->trace[0]); |
| SymbolizedStack *frame = Symbolizer::GetOrInit()->SymbolizePC(pc); |
| ReportErrorSummary(error_type, frame->info, alt_tool_name); |
| frame->ClearAll(); |
| #endif |
| } |
| |
| void ReportMmapWriteExec(int prot) { |
| #if SANITIZER_POSIX && (!SANITIZER_GO && !SANITIZER_ANDROID) |
| if ((prot & (PROT_WRITE | PROT_EXEC)) != (PROT_WRITE | PROT_EXEC)) |
| return; |
| |
| ScopedErrorReportLock l; |
| SanitizerCommonDecorator d; |
| |
| InternalMmapVector<BufferedStackTrace> stack_buffer(1); |
| BufferedStackTrace *stack = stack_buffer.data(); |
| stack->Reset(); |
| uptr top = 0; |
| uptr bottom = 0; |
| GET_CALLER_PC_BP_SP; |
| (void)sp; |
| bool fast = common_flags()->fast_unwind_on_fatal; |
| if (StackTrace::WillUseFastUnwind(fast)) { |
| GetThreadStackTopAndBottom(false, &top, &bottom); |
| stack->Unwind(kStackTraceMax, pc, bp, nullptr, top, bottom, true); |
| } else { |
| stack->Unwind(kStackTraceMax, pc, 0, nullptr, 0, 0, false); |
| } |
| |
| Printf("%s", d.Warning()); |
| Report("WARNING: %s: writable-executable page usage\n", SanitizerToolName); |
| Printf("%s", d.Default()); |
| |
| stack->Print(); |
| ReportErrorSummary("w-and-x-usage", stack); |
| #endif |
| } |
| |
| #if !SANITIZER_FUCHSIA && !SANITIZER_RTEMS && !SANITIZER_GO |
| void StartReportDeadlySignal() { |
| // Write the first message using fd=2, just in case. |
| // It may actually fail to write in case stderr is closed. |
| CatastrophicErrorWrite(SanitizerToolName, internal_strlen(SanitizerToolName)); |
| static const char kDeadlySignal[] = ":DEADLYSIGNAL\n"; |
| CatastrophicErrorWrite(kDeadlySignal, sizeof(kDeadlySignal) - 1); |
| } |
| |
| static void MaybeReportNonExecRegion(uptr pc) { |
| #if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD |
| MemoryMappingLayout proc_maps(/*cache_enabled*/ true); |
| MemoryMappedSegment segment; |
| while (proc_maps.Next(&segment)) { |
| if (pc >= segment.start && pc < segment.end && !segment.IsExecutable()) |
| Report("Hint: PC is at a non-executable region. Maybe a wild jump?\n"); |
| } |
| #endif |
| } |
| |
| static void PrintMemoryByte(InternalScopedString *str, const char *before, |
| u8 byte) { |
| SanitizerCommonDecorator d; |
| str->append("%s%s%x%x%s ", before, d.MemoryByte(), byte >> 4, byte & 15, |
| d.Default()); |
| } |
| |
| static void MaybeDumpInstructionBytes(uptr pc) { |
| if (!common_flags()->dump_instruction_bytes || (pc < GetPageSizeCached())) |
| return; |
| InternalScopedString str(1024); |
| str.append("First 16 instruction bytes at pc: "); |
| if (IsAccessibleMemoryRange(pc, 16)) { |
| for (int i = 0; i < 16; ++i) { |
| PrintMemoryByte(&str, "", ((u8 *)pc)[i]); |
| } |
| str.append("\n"); |
| } else { |
| str.append("unaccessible\n"); |
| } |
| Report("%s", str.data()); |
| } |
| |
| static void MaybeDumpRegisters(void *context) { |
| if (!common_flags()->dump_registers) return; |
| SignalContext::DumpAllRegisters(context); |
| } |
| |
| static void ReportStackOverflowImpl(const SignalContext &sig, u32 tid, |
| UnwindSignalStackCallbackType unwind, |
| const void *unwind_context) { |
| SanitizerCommonDecorator d; |
| Printf("%s", d.Warning()); |
| static const char kDescription[] = "stack-overflow"; |
| Report("ERROR: %s: %s on address %p (pc %p bp %p sp %p T%d)\n", |
| SanitizerToolName, kDescription, (void *)sig.addr, (void *)sig.pc, |
| (void *)sig.bp, (void *)sig.sp, tid); |
| Printf("%s", d.Default()); |
| InternalMmapVector<BufferedStackTrace> stack_buffer(1); |
| BufferedStackTrace *stack = stack_buffer.data(); |
| stack->Reset(); |
| unwind(sig, unwind_context, stack); |
| stack->Print(); |
| ReportErrorSummary(kDescription, stack); |
| } |
| |
| static void ReportDeadlySignalImpl(const SignalContext &sig, u32 tid, |
| UnwindSignalStackCallbackType unwind, |
| const void *unwind_context) { |
| SanitizerCommonDecorator d; |
| Printf("%s", d.Warning()); |
| const char *description = sig.Describe(); |
| if (sig.is_memory_access && !sig.is_true_faulting_addr) |
| Report("ERROR: %s: %s on unknown address (pc %p bp %p sp %p T%d)\n", |
| SanitizerToolName, description, (void *)sig.pc, (void *)sig.bp, |
| (void *)sig.sp, tid); |
| else |
| Report("ERROR: %s: %s on unknown address %p (pc %p bp %p sp %p T%d)\n", |
| SanitizerToolName, description, (void *)sig.addr, (void *)sig.pc, |
| (void *)sig.bp, (void *)sig.sp, tid); |
| Printf("%s", d.Default()); |
| if (sig.pc < GetPageSizeCached()) |
| Report("Hint: pc points to the zero page.\n"); |
| if (sig.is_memory_access) { |
| const char *access_type = |
| sig.write_flag == SignalContext::WRITE |
| ? "WRITE" |
| : (sig.write_flag == SignalContext::READ ? "READ" : "UNKNOWN"); |
| Report("The signal is caused by a %s memory access.\n", access_type); |
| if (!sig.is_true_faulting_addr) |
| Report("Hint: this fault was caused by a dereference of a high value " |
| "address (see register values below). Disassemble the provided " |
| "pc to learn which register was used.\n"); |
| else if (sig.addr < GetPageSizeCached()) |
| Report("Hint: address points to the zero page.\n"); |
| } |
| MaybeReportNonExecRegion(sig.pc); |
| InternalMmapVector<BufferedStackTrace> stack_buffer(1); |
| BufferedStackTrace *stack = stack_buffer.data(); |
| stack->Reset(); |
| unwind(sig, unwind_context, stack); |
| stack->Print(); |
| MaybeDumpInstructionBytes(sig.pc); |
| MaybeDumpRegisters(sig.context); |
| Printf("%s can not provide additional info.\n", SanitizerToolName); |
| ReportErrorSummary(description, stack); |
| } |
| |
| void ReportDeadlySignal(const SignalContext &sig, u32 tid, |
| UnwindSignalStackCallbackType unwind, |
| const void *unwind_context) { |
| if (sig.IsStackOverflow()) |
| ReportStackOverflowImpl(sig, tid, unwind, unwind_context); |
| else |
| ReportDeadlySignalImpl(sig, tid, unwind, unwind_context); |
| } |
| |
| void HandleDeadlySignal(void *siginfo, void *context, u32 tid, |
| UnwindSignalStackCallbackType unwind, |
| const void *unwind_context) { |
| StartReportDeadlySignal(); |
| ScopedErrorReportLock rl; |
| SignalContext sig(siginfo, context); |
| ReportDeadlySignal(sig, tid, unwind, unwind_context); |
| Report("ABORTING\n"); |
| Die(); |
| } |
| |
| #endif // !SANITIZER_FUCHSIA && !SANITIZER_GO |
| |
| static atomic_uintptr_t reporting_thread = {0}; |
| static StaticSpinMutex CommonSanitizerReportMutex; |
| |
| ScopedErrorReportLock::ScopedErrorReportLock() { |
| uptr current = GetThreadSelf(); |
| for (;;) { |
| uptr expected = 0; |
| if (atomic_compare_exchange_strong(&reporting_thread, &expected, current, |
| memory_order_relaxed)) { |
| // We've claimed reporting_thread so proceed. |
| CommonSanitizerReportMutex.Lock(); |
| return; |
| } |
| |
| if (expected == current) { |
| // This is either asynch signal or nested error during error reporting. |
| // Fail simple to avoid deadlocks in Report(). |
| |
| // Can't use Report() here because of potential deadlocks in nested |
| // signal handlers. |
| CatastrophicErrorWrite(SanitizerToolName, |
| internal_strlen(SanitizerToolName)); |
| static const char msg[] = ": nested bug in the same thread, aborting.\n"; |
| CatastrophicErrorWrite(msg, sizeof(msg) - 1); |
| |
| internal__exit(common_flags()->exitcode); |
| } |
| |
| internal_sched_yield(); |
| } |
| } |
| |
| ScopedErrorReportLock::~ScopedErrorReportLock() { |
| CommonSanitizerReportMutex.Unlock(); |
| atomic_store_relaxed(&reporting_thread, 0); |
| } |
| |
| void ScopedErrorReportLock::CheckLocked() { |
| CommonSanitizerReportMutex.CheckLocked(); |
| } |
| |
| } // namespace __sanitizer |