700 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			700 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			C++
		
	
	
	
//===- FuzzerTracePC.cpp - PC tracing--------------------------------------===//
 | 
						|
//
 | 
						|
//                     The LLVM Compiler Infrastructure
 | 
						|
//
 | 
						|
// This file is distributed under the University of Illinois Open Source
 | 
						|
// License. See LICENSE.TXT for details.
 | 
						|
//
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
// Trace PCs.
 | 
						|
// This module implements __sanitizer_cov_trace_pc_guard[_init],
 | 
						|
// the callback required for -fsanitize-coverage=trace-pc-guard instrumentation.
 | 
						|
//
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
 | 
						|
#include "FuzzerTracePC.h"
 | 
						|
#include "FuzzerCorpus.h"
 | 
						|
#include "FuzzerDefs.h"
 | 
						|
#include "FuzzerDictionary.h"
 | 
						|
#include "FuzzerExtFunctions.h"
 | 
						|
#include "FuzzerIO.h"
 | 
						|
#include "FuzzerUtil.h"
 | 
						|
#include "FuzzerValueBitMap.h"
 | 
						|
#include <set>
 | 
						|
 | 
						|
// The coverage counters and PCs.
 | 
						|
// These are declared as global variables named "__sancov_*" to simplify
 | 
						|
// experiments with inlined instrumentation.
 | 
						|
alignas(64) ATTRIBUTE_INTERFACE
 | 
						|
uint8_t __sancov_trace_pc_guard_8bit_counters[fuzzer::TracePC::kNumPCs];
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
uintptr_t __sancov_trace_pc_pcs[fuzzer::TracePC::kNumPCs];
 | 
						|
 | 
						|
// Used by -fsanitize-coverage=stack-depth to track stack depth
 | 
						|
ATTRIBUTE_INTERFACE __attribute__((tls_model("initial-exec")))
 | 
						|
thread_local uintptr_t __sancov_lowest_stack;
 | 
						|
 | 
						|
namespace fuzzer {
 | 
						|
 | 
						|
TracePC TPC;
 | 
						|
 | 
						|
uint8_t *TracePC::Counters() const {
 | 
						|
  return __sancov_trace_pc_guard_8bit_counters;
 | 
						|
}
 | 
						|
 | 
						|
uintptr_t *TracePC::PCs() const {
 | 
						|
  return __sancov_trace_pc_pcs;
 | 
						|
}
 | 
						|
 | 
						|
size_t TracePC::GetTotalPCCoverage() {
 | 
						|
  if (ObservedPCs.size())
 | 
						|
    return ObservedPCs.size();
 | 
						|
  size_t Res = 0;
 | 
						|
  for (size_t i = 1, N = GetNumPCs(); i < N; i++)
 | 
						|
    if (PCs()[i])
 | 
						|
      Res++;
 | 
						|
  return Res;
 | 
						|
}
 | 
						|
 | 
						|
template<class CallBack>
 | 
						|
void TracePC::IterateInline8bitCounters(CallBack CB) const {
 | 
						|
  if (NumInline8bitCounters && NumInline8bitCounters == NumPCsInPCTables) {
 | 
						|
    size_t CounterIdx = 0;
 | 
						|
    for (size_t i = 0; i < NumModulesWithInline8bitCounters; i++) {
 | 
						|
      uint8_t *Beg = ModuleCounters[i].Start;
 | 
						|
      size_t Size = ModuleCounters[i].Stop - Beg;
 | 
						|
      assert(Size == (size_t)(ModulePCTable[i].Stop - ModulePCTable[i].Start));
 | 
						|
      for (size_t j = 0; j < Size; j++, CounterIdx++)
 | 
						|
        CB(i, j, CounterIdx);
 | 
						|
    }
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
// Initializes unstable counters by copying Inline8bitCounters to unstable
 | 
						|
// counters.
 | 
						|
void TracePC::InitializeUnstableCounters() {
 | 
						|
  IterateInline8bitCounters([&](int i, int j, int UnstableIdx) {
 | 
						|
    UnstableCounters[UnstableIdx].Counter = ModuleCounters[i].Start[j];
 | 
						|
  });
 | 
						|
}
 | 
						|
 | 
						|
// Compares the current counters with counters from previous runs
 | 
						|
// and records differences as unstable edges.
 | 
						|
bool TracePC::UpdateUnstableCounters(int UnstableMode) {
 | 
						|
  bool Updated = false;
 | 
						|
  IterateInline8bitCounters([&](int i, int j, int UnstableIdx) {
 | 
						|
    if (ModuleCounters[i].Start[j] != UnstableCounters[UnstableIdx].Counter) {
 | 
						|
      Updated = true;
 | 
						|
      UnstableCounters[UnstableIdx].IsUnstable = true;
 | 
						|
      if (UnstableMode == ZeroUnstable)
 | 
						|
        UnstableCounters[UnstableIdx].Counter = 0;
 | 
						|
      else if (UnstableMode == MinUnstable)
 | 
						|
        UnstableCounters[UnstableIdx].Counter = std::min(
 | 
						|
            ModuleCounters[i].Start[j], UnstableCounters[UnstableIdx].Counter);
 | 
						|
    }
 | 
						|
  });
 | 
						|
  return Updated;
 | 
						|
}
 | 
						|
 | 
						|
// Updates and applies unstable counters to ModuleCounters in single iteration
 | 
						|
void TracePC::UpdateAndApplyUnstableCounters(int UnstableMode) {
 | 
						|
  IterateInline8bitCounters([&](int i, int j, int UnstableIdx) {
 | 
						|
    if (ModuleCounters[i].Start[j] != UnstableCounters[UnstableIdx].Counter) {
 | 
						|
      UnstableCounters[UnstableIdx].IsUnstable = true;
 | 
						|
      if (UnstableMode == ZeroUnstable)
 | 
						|
        ModuleCounters[i].Start[j] = 0;
 | 
						|
      else if (UnstableMode == MinUnstable)
 | 
						|
        ModuleCounters[i].Start[j] = std::min(
 | 
						|
            ModuleCounters[i].Start[j], UnstableCounters[UnstableIdx].Counter);
 | 
						|
    }
 | 
						|
  });
 | 
						|
}
 | 
						|
 | 
						|
void TracePC::HandleInline8bitCountersInit(uint8_t *Start, uint8_t *Stop) {
 | 
						|
  if (Start == Stop) return;
 | 
						|
  if (NumModulesWithInline8bitCounters &&
 | 
						|
      ModuleCounters[NumModulesWithInline8bitCounters-1].Start == Start) return;
 | 
						|
  assert(NumModulesWithInline8bitCounters <
 | 
						|
         sizeof(ModuleCounters) / sizeof(ModuleCounters[0]));
 | 
						|
  ModuleCounters[NumModulesWithInline8bitCounters++] = {Start, Stop};
 | 
						|
  NumInline8bitCounters += Stop - Start;
 | 
						|
}
 | 
						|
 | 
						|
void TracePC::HandlePCsInit(const uintptr_t *Start, const uintptr_t *Stop) {
 | 
						|
  const PCTableEntry *B = reinterpret_cast<const PCTableEntry *>(Start);
 | 
						|
  const PCTableEntry *E = reinterpret_cast<const PCTableEntry *>(Stop);
 | 
						|
  if (NumPCTables && ModulePCTable[NumPCTables - 1].Start == B) return;
 | 
						|
  assert(NumPCTables < sizeof(ModulePCTable) / sizeof(ModulePCTable[0]));
 | 
						|
  ModulePCTable[NumPCTables++] = {B, E};
 | 
						|
  NumPCsInPCTables += E - B;
 | 
						|
}
 | 
						|
 | 
						|
void TracePC::HandleInit(uint32_t *Start, uint32_t *Stop) {
 | 
						|
  if (Start == Stop || *Start) return;
 | 
						|
  assert(NumModules < sizeof(Modules) / sizeof(Modules[0]));
 | 
						|
  for (uint32_t *P = Start; P < Stop; P++) {
 | 
						|
    NumGuards++;
 | 
						|
    if (NumGuards == kNumPCs) {
 | 
						|
      RawPrint(
 | 
						|
          "WARNING: The binary has too many instrumented PCs.\n"
 | 
						|
          "         You may want to reduce the size of the binary\n"
 | 
						|
          "         for more efficient fuzzing and precise coverage data\n");
 | 
						|
    }
 | 
						|
    *P = NumGuards % kNumPCs;
 | 
						|
  }
 | 
						|
  Modules[NumModules].Start = Start;
 | 
						|
  Modules[NumModules].Stop = Stop;
 | 
						|
  NumModules++;
 | 
						|
}
 | 
						|
 | 
						|
void TracePC::PrintModuleInfo() {
 | 
						|
  if (NumGuards) {
 | 
						|
    Printf("INFO: Loaded %zd modules   (%zd guards): ", NumModules, NumGuards);
 | 
						|
    for (size_t i = 0; i < NumModules; i++)
 | 
						|
      Printf("%zd [%p, %p), ", Modules[i].Stop - Modules[i].Start,
 | 
						|
             Modules[i].Start, Modules[i].Stop);
 | 
						|
    Printf("\n");
 | 
						|
  }
 | 
						|
  if (NumModulesWithInline8bitCounters) {
 | 
						|
    Printf("INFO: Loaded %zd modules   (%zd inline 8-bit counters): ",
 | 
						|
           NumModulesWithInline8bitCounters, NumInline8bitCounters);
 | 
						|
    for (size_t i = 0; i < NumModulesWithInline8bitCounters; i++)
 | 
						|
      Printf("%zd [%p, %p), ", ModuleCounters[i].Stop - ModuleCounters[i].Start,
 | 
						|
             ModuleCounters[i].Start, ModuleCounters[i].Stop);
 | 
						|
    Printf("\n");
 | 
						|
  }
 | 
						|
  if (NumPCTables) {
 | 
						|
    Printf("INFO: Loaded %zd PC tables (%zd PCs): ", NumPCTables,
 | 
						|
           NumPCsInPCTables);
 | 
						|
    for (size_t i = 0; i < NumPCTables; i++) {
 | 
						|
      Printf("%zd [%p,%p), ", ModulePCTable[i].Stop - ModulePCTable[i].Start,
 | 
						|
             ModulePCTable[i].Start, ModulePCTable[i].Stop);
 | 
						|
    }
 | 
						|
    Printf("\n");
 | 
						|
 | 
						|
    if ((NumGuards && NumGuards != NumPCsInPCTables) ||
 | 
						|
        (NumInline8bitCounters && NumInline8bitCounters != NumPCsInPCTables)) {
 | 
						|
      Printf("ERROR: The size of coverage PC tables does not match the\n"
 | 
						|
             "number of instrumented PCs. This might be a compiler bug,\n"
 | 
						|
             "please contact the libFuzzer developers.\n"
 | 
						|
             "Also check https://bugs.llvm.org/show_bug.cgi?id=34636\n"
 | 
						|
             "for possible workarounds (tl;dr: don't use the old GNU ld)\n");
 | 
						|
      _Exit(1);
 | 
						|
    }
 | 
						|
  }
 | 
						|
  if (size_t NumExtraCounters = ExtraCountersEnd() - ExtraCountersBegin())
 | 
						|
    Printf("INFO: %zd Extra Counters\n", NumExtraCounters);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
void TracePC::HandleCallerCallee(uintptr_t Caller, uintptr_t Callee) {
 | 
						|
  const uintptr_t kBits = 12;
 | 
						|
  const uintptr_t kMask = (1 << kBits) - 1;
 | 
						|
  uintptr_t Idx = (Caller & kMask) | ((Callee & kMask) << kBits);
 | 
						|
  ValueProfileMap.AddValueModPrime(Idx);
 | 
						|
}
 | 
						|
 | 
						|
void TracePC::UpdateObservedPCs() {
 | 
						|
  Vector<uintptr_t> CoveredFuncs;
 | 
						|
  auto ObservePC = [&](uintptr_t PC) {
 | 
						|
    if (ObservedPCs.insert(PC).second && DoPrintNewPCs) {
 | 
						|
      PrintPC("\tNEW_PC: %p %F %L", "\tNEW_PC: %p", PC + 1);
 | 
						|
      Printf("\n");
 | 
						|
    }
 | 
						|
  };
 | 
						|
 | 
						|
  auto Observe = [&](const PCTableEntry &TE) {
 | 
						|
    if (TE.PCFlags & 1)
 | 
						|
      if (++ObservedFuncs[TE.PC] == 1 && NumPrintNewFuncs)
 | 
						|
        CoveredFuncs.push_back(TE.PC);
 | 
						|
    ObservePC(TE.PC);
 | 
						|
  };
 | 
						|
 | 
						|
  if (NumPCsInPCTables) {
 | 
						|
    if (NumInline8bitCounters == NumPCsInPCTables) {
 | 
						|
      IterateInline8bitCounters([&](int i, int j, int CounterIdx) {
 | 
						|
        if (ModuleCounters[i].Start[j])
 | 
						|
          Observe(ModulePCTable[i].Start[j]);
 | 
						|
      });
 | 
						|
    } else if (NumGuards == NumPCsInPCTables) {
 | 
						|
      size_t GuardIdx = 1;
 | 
						|
      for (size_t i = 0; i < NumModules; i++) {
 | 
						|
        uint32_t *Beg = Modules[i].Start;
 | 
						|
        size_t Size = Modules[i].Stop - Beg;
 | 
						|
        assert(Size ==
 | 
						|
               (size_t)(ModulePCTable[i].Stop - ModulePCTable[i].Start));
 | 
						|
        for (size_t j = 0; j < Size; j++, GuardIdx++)
 | 
						|
          if (Counters()[GuardIdx])
 | 
						|
            Observe(ModulePCTable[i].Start[j]);
 | 
						|
      }
 | 
						|
    }
 | 
						|
  }
 | 
						|
 | 
						|
  for (size_t i = 0, N = Min(CoveredFuncs.size(), NumPrintNewFuncs); i < N;
 | 
						|
       i++) {
 | 
						|
    Printf("\tNEW_FUNC[%zd/%zd]: ", i + 1, CoveredFuncs.size());
 | 
						|
    PrintPC("%p %F %L", "%p", CoveredFuncs[i] + 1);
 | 
						|
    Printf("\n");
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
inline ALWAYS_INLINE uintptr_t GetPreviousInstructionPc(uintptr_t PC) {
 | 
						|
  // TODO: this implementation is x86 only.
 | 
						|
  // see sanitizer_common GetPreviousInstructionPc for full implementation.
 | 
						|
  return PC - 1;
 | 
						|
}
 | 
						|
 | 
						|
inline ALWAYS_INLINE uintptr_t GetNextInstructionPc(uintptr_t PC) {
 | 
						|
  // TODO: this implementation is x86 only.
 | 
						|
  // see sanitizer_common GetPreviousInstructionPc for full implementation.
 | 
						|
  return PC + 1;
 | 
						|
}
 | 
						|
 | 
						|
static std::string GetModuleName(uintptr_t PC) {
 | 
						|
  char ModulePathRaw[4096] = "";  // What's PATH_MAX in portable C++?
 | 
						|
  void *OffsetRaw = nullptr;
 | 
						|
  if (!EF->__sanitizer_get_module_and_offset_for_pc(
 | 
						|
      reinterpret_cast<void *>(PC), ModulePathRaw,
 | 
						|
      sizeof(ModulePathRaw), &OffsetRaw))
 | 
						|
    return "";
 | 
						|
  return ModulePathRaw;
 | 
						|
}
 | 
						|
 | 
						|
template<class CallBack>
 | 
						|
void TracePC::IterateCoveredFunctions(CallBack CB) {
 | 
						|
  for (size_t i = 0; i < NumPCTables; i++) {
 | 
						|
    auto &M = ModulePCTable[i];
 | 
						|
    assert(M.Start < M.Stop);
 | 
						|
    auto ModuleName = GetModuleName(M.Start->PC);
 | 
						|
    for (auto NextFE = M.Start; NextFE < M.Stop; ) {
 | 
						|
      auto FE = NextFE;
 | 
						|
      assert((FE->PCFlags & 1) && "Not a function entry point");
 | 
						|
      do {
 | 
						|
        NextFE++;
 | 
						|
      } while (NextFE < M.Stop && !(NextFE->PCFlags & 1));
 | 
						|
      if (ObservedFuncs.count(FE->PC))
 | 
						|
        CB(FE, NextFE, ObservedFuncs[FE->PC]);
 | 
						|
    }
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
void TracePC::SetFocusFunction(const std::string &FuncName) {
 | 
						|
  // This function should be called once.
 | 
						|
  assert(FocusFunction.first > NumModulesWithInline8bitCounters);
 | 
						|
  if (FuncName.empty())
 | 
						|
    return;
 | 
						|
  for (size_t M = 0; M < NumModulesWithInline8bitCounters; M++) {
 | 
						|
    auto &PCTE = ModulePCTable[M];
 | 
						|
    size_t N = PCTE.Stop - PCTE.Start;
 | 
						|
    for (size_t I = 0; I < N; I++) {
 | 
						|
      if (!(PCTE.Start[I].PCFlags & 1)) continue;  // not a function entry.
 | 
						|
      auto Name = DescribePC("%F", GetNextInstructionPc(PCTE.Start[I].PC));
 | 
						|
      if (Name[0] == 'i' && Name[1] == 'n' && Name[2] == ' ')
 | 
						|
        Name = Name.substr(3, std::string::npos);
 | 
						|
      if (FuncName != Name) continue;
 | 
						|
      Printf("INFO: Focus function is set to '%s'\n", Name.c_str());
 | 
						|
      FocusFunction = {M, I};
 | 
						|
      return;
 | 
						|
    }
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
bool TracePC::ObservedFocusFunction() {
 | 
						|
  size_t I = FocusFunction.first;
 | 
						|
  size_t J = FocusFunction.second;
 | 
						|
  if (I >= NumModulesWithInline8bitCounters)
 | 
						|
    return false;
 | 
						|
  auto &MC = ModuleCounters[I];
 | 
						|
  size_t Size = MC.Stop - MC.Start;
 | 
						|
  if (J >= Size)
 | 
						|
    return false;
 | 
						|
  return MC.Start[J] != 0;
 | 
						|
}
 | 
						|
 | 
						|
void TracePC::PrintCoverage() {
 | 
						|
  if (!EF->__sanitizer_symbolize_pc ||
 | 
						|
      !EF->__sanitizer_get_module_and_offset_for_pc) {
 | 
						|
    Printf("INFO: __sanitizer_symbolize_pc or "
 | 
						|
           "__sanitizer_get_module_and_offset_for_pc is not available,"
 | 
						|
           " not printing coverage\n");
 | 
						|
    return;
 | 
						|
  }
 | 
						|
  Printf("COVERAGE:\n");
 | 
						|
  auto CoveredFunctionCallback = [&](const PCTableEntry *First,
 | 
						|
                                     const PCTableEntry *Last,
 | 
						|
                                     uintptr_t Counter) {
 | 
						|
    assert(First < Last);
 | 
						|
    auto VisualizePC = GetNextInstructionPc(First->PC);
 | 
						|
    std::string FileStr = DescribePC("%s", VisualizePC);
 | 
						|
    if (!IsInterestingCoverageFile(FileStr))
 | 
						|
      return;
 | 
						|
    std::string FunctionStr = DescribePC("%F", VisualizePC);
 | 
						|
    if (FunctionStr.find("in ") == 0)
 | 
						|
      FunctionStr = FunctionStr.substr(3);
 | 
						|
    std::string LineStr = DescribePC("%l", VisualizePC);
 | 
						|
    size_t Line = std::stoul(LineStr);
 | 
						|
    size_t NumEdges = Last - First;
 | 
						|
    Vector<uintptr_t> UncoveredPCs;
 | 
						|
    for (auto TE = First; TE < Last; TE++)
 | 
						|
      if (!ObservedPCs.count(TE->PC))
 | 
						|
        UncoveredPCs.push_back(TE->PC);
 | 
						|
    Printf("COVERED_FUNC: hits: %zd", Counter);
 | 
						|
    Printf(" edges: %zd/%zd", NumEdges - UncoveredPCs.size(), NumEdges);
 | 
						|
    Printf(" %s %s:%zd\n", FunctionStr.c_str(), FileStr.c_str(), Line);
 | 
						|
    for (auto PC: UncoveredPCs)
 | 
						|
      Printf("  UNCOVERED_PC: %s\n",
 | 
						|
             DescribePC("%s:%l", GetNextInstructionPc(PC)).c_str());
 | 
						|
  };
 | 
						|
 | 
						|
  IterateCoveredFunctions(CoveredFunctionCallback);
 | 
						|
}
 | 
						|
 | 
						|
void TracePC::DumpCoverage() {
 | 
						|
  if (EF->__sanitizer_dump_coverage) {
 | 
						|
    Vector<uintptr_t> PCsCopy(GetNumPCs());
 | 
						|
    for (size_t i = 0; i < GetNumPCs(); i++)
 | 
						|
      PCsCopy[i] = PCs()[i] ? GetPreviousInstructionPc(PCs()[i]) : 0;
 | 
						|
    EF->__sanitizer_dump_coverage(PCsCopy.data(), PCsCopy.size());
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
void TracePC::PrintUnstableStats() {
 | 
						|
  size_t count = 0;
 | 
						|
  Printf("UNSTABLE_FUNCTIONS:\n");
 | 
						|
  IterateInline8bitCounters([&](int i, int j, int UnstableIdx) {
 | 
						|
    const PCTableEntry &TE = ModulePCTable[i].Start[j];
 | 
						|
    if (UnstableCounters[UnstableIdx].IsUnstable) {
 | 
						|
      count++;
 | 
						|
      if (ObservedFuncs.count(TE.PC)) {
 | 
						|
        auto VisualizePC = GetNextInstructionPc(TE.PC);
 | 
						|
        std::string FunctionStr = DescribePC("%F", VisualizePC);
 | 
						|
        if (FunctionStr.find("in ") == 0)
 | 
						|
          FunctionStr = FunctionStr.substr(3);
 | 
						|
        Printf("%s\n", FunctionStr.c_str());
 | 
						|
      }
 | 
						|
    }
 | 
						|
  });
 | 
						|
 | 
						|
  Printf("stat::stability_rate: %.2f\n",
 | 
						|
         100 - static_cast<float>(count * 100) / NumInline8bitCounters);
 | 
						|
}
 | 
						|
 | 
						|
// Value profile.
 | 
						|
// We keep track of various values that affect control flow.
 | 
						|
// These values are inserted into a bit-set-based hash map.
 | 
						|
// Every new bit in the map is treated as a new coverage.
 | 
						|
//
 | 
						|
// For memcmp/strcmp/etc the interesting value is the length of the common
 | 
						|
// prefix of the parameters.
 | 
						|
// For cmp instructions the interesting value is a XOR of the parameters.
 | 
						|
// The interesting value is mixed up with the PC and is then added to the map.
 | 
						|
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
void TracePC::AddValueForMemcmp(void *caller_pc, const void *s1, const void *s2,
 | 
						|
                                size_t n, bool StopAtZero) {
 | 
						|
  if (!n) return;
 | 
						|
  size_t Len = std::min(n, Word::GetMaxSize());
 | 
						|
  const uint8_t *A1 = reinterpret_cast<const uint8_t *>(s1);
 | 
						|
  const uint8_t *A2 = reinterpret_cast<const uint8_t *>(s2);
 | 
						|
  uint8_t B1[Word::kMaxSize];
 | 
						|
  uint8_t B2[Word::kMaxSize];
 | 
						|
  // Copy the data into locals in this non-msan-instrumented function
 | 
						|
  // to avoid msan complaining further.
 | 
						|
  size_t Hash = 0;  // Compute some simple hash of both strings.
 | 
						|
  for (size_t i = 0; i < Len; i++) {
 | 
						|
    B1[i] = A1[i];
 | 
						|
    B2[i] = A2[i];
 | 
						|
    size_t T = B1[i];
 | 
						|
    Hash ^= (T << 8) | B2[i];
 | 
						|
  }
 | 
						|
  size_t I = 0;
 | 
						|
  for (; I < Len; I++)
 | 
						|
    if (B1[I] != B2[I] || (StopAtZero && B1[I] == 0))
 | 
						|
      break;
 | 
						|
  size_t PC = reinterpret_cast<size_t>(caller_pc);
 | 
						|
  size_t Idx = (PC & 4095) | (I << 12);
 | 
						|
  ValueProfileMap.AddValue(Idx);
 | 
						|
  TORCW.Insert(Idx ^ Hash, Word(B1, Len), Word(B2, Len));
 | 
						|
}
 | 
						|
 | 
						|
template <class T>
 | 
						|
ATTRIBUTE_TARGET_POPCNT ALWAYS_INLINE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
void TracePC::HandleCmp(uintptr_t PC, T Arg1, T Arg2) {
 | 
						|
  uint64_t ArgXor = Arg1 ^ Arg2;
 | 
						|
  if (sizeof(T) == 4)
 | 
						|
      TORC4.Insert(ArgXor, Arg1, Arg2);
 | 
						|
  else if (sizeof(T) == 8)
 | 
						|
      TORC8.Insert(ArgXor, Arg1, Arg2);
 | 
						|
  uint64_t HammingDistance = __builtin_popcountll(ArgXor); // [0,64]
 | 
						|
  uint64_t AbsoluteDistance =
 | 
						|
      (Arg1 == Arg2 ? 0 : __builtin_clzll(Arg1 - Arg2) + 1);
 | 
						|
  ValueProfileMap.AddValue(PC * 128 + HammingDistance);
 | 
						|
  ValueProfileMap.AddValue(PC * 128 + 64 + AbsoluteDistance);
 | 
						|
}
 | 
						|
 | 
						|
static size_t InternalStrnlen(const char *S, size_t MaxLen) {
 | 
						|
  size_t Len = 0;
 | 
						|
  for (; Len < MaxLen && S[Len]; Len++) {}
 | 
						|
  return Len;
 | 
						|
}
 | 
						|
 | 
						|
// Finds min of (strlen(S1), strlen(S2)).
 | 
						|
// Needed bacause one of these strings may actually be non-zero terminated.
 | 
						|
static size_t InternalStrnlen2(const char *S1, const char *S2) {
 | 
						|
  size_t Len = 0;
 | 
						|
  for (; S1[Len] && S2[Len]; Len++)  {}
 | 
						|
  return Len;
 | 
						|
}
 | 
						|
 | 
						|
void TracePC::ClearInlineCounters() {
 | 
						|
  for (size_t i = 0; i < NumModulesWithInline8bitCounters; i++) {
 | 
						|
    uint8_t *Beg = ModuleCounters[i].Start;
 | 
						|
    size_t Size = ModuleCounters[i].Stop - Beg;
 | 
						|
    memset(Beg, 0, Size);
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
void TracePC::RecordInitialStack() {
 | 
						|
  int stack;
 | 
						|
  __sancov_lowest_stack = InitialStack = reinterpret_cast<uintptr_t>(&stack);
 | 
						|
}
 | 
						|
 | 
						|
uintptr_t TracePC::GetMaxStackOffset() const {
 | 
						|
  return InitialStack - __sancov_lowest_stack;  // Stack grows down
 | 
						|
}
 | 
						|
 | 
						|
} // namespace fuzzer
 | 
						|
 | 
						|
extern "C" {
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
void __sanitizer_cov_trace_pc_guard(uint32_t *Guard) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  uint32_t Idx = *Guard;
 | 
						|
  __sancov_trace_pc_pcs[Idx] = PC;
 | 
						|
  __sancov_trace_pc_guard_8bit_counters[Idx]++;
 | 
						|
}
 | 
						|
 | 
						|
// Best-effort support for -fsanitize-coverage=trace-pc, which is available
 | 
						|
// in both Clang and GCC.
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
void __sanitizer_cov_trace_pc() {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  uintptr_t Idx = PC & (((uintptr_t)1 << fuzzer::TracePC::kTracePcBits) - 1);
 | 
						|
  __sancov_trace_pc_pcs[Idx] = PC;
 | 
						|
  __sancov_trace_pc_guard_8bit_counters[Idx]++;
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
void __sanitizer_cov_trace_pc_guard_init(uint32_t *Start, uint32_t *Stop) {
 | 
						|
  fuzzer::TPC.HandleInit(Start, Stop);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
void __sanitizer_cov_8bit_counters_init(uint8_t *Start, uint8_t *Stop) {
 | 
						|
  fuzzer::TPC.HandleInline8bitCountersInit(Start, Stop);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
void __sanitizer_cov_pcs_init(const uintptr_t *pcs_beg,
 | 
						|
                              const uintptr_t *pcs_end) {
 | 
						|
  fuzzer::TPC.HandlePCsInit(pcs_beg, pcs_end);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
void __sanitizer_cov_trace_pc_indir(uintptr_t Callee) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  fuzzer::TPC.HandleCallerCallee(PC, Callee);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
ATTRIBUTE_TARGET_POPCNT
 | 
						|
void __sanitizer_cov_trace_cmp8(uint64_t Arg1, uint64_t Arg2) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
ATTRIBUTE_TARGET_POPCNT
 | 
						|
// Now the __sanitizer_cov_trace_const_cmp[1248] callbacks just mimic
 | 
						|
// the behaviour of __sanitizer_cov_trace_cmp[1248] ones. This, however,
 | 
						|
// should be changed later to make full use of instrumentation.
 | 
						|
void __sanitizer_cov_trace_const_cmp8(uint64_t Arg1, uint64_t Arg2) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
ATTRIBUTE_TARGET_POPCNT
 | 
						|
void __sanitizer_cov_trace_cmp4(uint32_t Arg1, uint32_t Arg2) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
ATTRIBUTE_TARGET_POPCNT
 | 
						|
void __sanitizer_cov_trace_const_cmp4(uint32_t Arg1, uint32_t Arg2) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
ATTRIBUTE_TARGET_POPCNT
 | 
						|
void __sanitizer_cov_trace_cmp2(uint16_t Arg1, uint16_t Arg2) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
ATTRIBUTE_TARGET_POPCNT
 | 
						|
void __sanitizer_cov_trace_const_cmp2(uint16_t Arg1, uint16_t Arg2) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
ATTRIBUTE_TARGET_POPCNT
 | 
						|
void __sanitizer_cov_trace_cmp1(uint8_t Arg1, uint8_t Arg2) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
ATTRIBUTE_TARGET_POPCNT
 | 
						|
void __sanitizer_cov_trace_const_cmp1(uint8_t Arg1, uint8_t Arg2) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
ATTRIBUTE_TARGET_POPCNT
 | 
						|
void __sanitizer_cov_trace_switch(uint64_t Val, uint64_t *Cases) {
 | 
						|
  uint64_t N = Cases[0];
 | 
						|
  uint64_t ValSizeInBits = Cases[1];
 | 
						|
  uint64_t *Vals = Cases + 2;
 | 
						|
  // Skip the most common and the most boring case.
 | 
						|
  if (Vals[N - 1]  < 256 && Val < 256)
 | 
						|
    return;
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  size_t i;
 | 
						|
  uint64_t Token = 0;
 | 
						|
  for (i = 0; i < N; i++) {
 | 
						|
    Token = Val ^ Vals[i];
 | 
						|
    if (Val < Vals[i])
 | 
						|
      break;
 | 
						|
  }
 | 
						|
 | 
						|
  if (ValSizeInBits == 16)
 | 
						|
    fuzzer::TPC.HandleCmp(PC + i, static_cast<uint16_t>(Token), (uint16_t)(0));
 | 
						|
  else if (ValSizeInBits == 32)
 | 
						|
    fuzzer::TPC.HandleCmp(PC + i, static_cast<uint32_t>(Token), (uint32_t)(0));
 | 
						|
  else
 | 
						|
    fuzzer::TPC.HandleCmp(PC + i, Token, (uint64_t)(0));
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
ATTRIBUTE_TARGET_POPCNT
 | 
						|
void __sanitizer_cov_trace_div4(uint32_t Val) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  fuzzer::TPC.HandleCmp(PC, Val, (uint32_t)0);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
ATTRIBUTE_TARGET_POPCNT
 | 
						|
void __sanitizer_cov_trace_div8(uint64_t Val) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  fuzzer::TPC.HandleCmp(PC, Val, (uint64_t)0);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE
 | 
						|
ATTRIBUTE_NO_SANITIZE_ALL
 | 
						|
ATTRIBUTE_TARGET_POPCNT
 | 
						|
void __sanitizer_cov_trace_gep(uintptr_t Idx) {
 | 
						|
  uintptr_t PC = reinterpret_cast<uintptr_t>(__builtin_return_address(0));
 | 
						|
  fuzzer::TPC.HandleCmp(PC, Idx, (uintptr_t)0);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
 | 
						|
void __sanitizer_weak_hook_memcmp(void *caller_pc, const void *s1,
 | 
						|
                                  const void *s2, size_t n, int result) {
 | 
						|
  if (!fuzzer::RunningUserCallback) return;
 | 
						|
  if (result == 0) return;  // No reason to mutate.
 | 
						|
  if (n <= 1) return;  // Not interesting.
 | 
						|
  fuzzer::TPC.AddValueForMemcmp(caller_pc, s1, s2, n, /*StopAtZero*/false);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
 | 
						|
void __sanitizer_weak_hook_strncmp(void *caller_pc, const char *s1,
 | 
						|
                                   const char *s2, size_t n, int result) {
 | 
						|
  if (!fuzzer::RunningUserCallback) return;
 | 
						|
  if (result == 0) return;  // No reason to mutate.
 | 
						|
  size_t Len1 = fuzzer::InternalStrnlen(s1, n);
 | 
						|
  size_t Len2 = fuzzer::InternalStrnlen(s2, n);
 | 
						|
  n = std::min(n, Len1);
 | 
						|
  n = std::min(n, Len2);
 | 
						|
  if (n <= 1) return;  // Not interesting.
 | 
						|
  fuzzer::TPC.AddValueForMemcmp(caller_pc, s1, s2, n, /*StopAtZero*/true);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
 | 
						|
void __sanitizer_weak_hook_strcmp(void *caller_pc, const char *s1,
 | 
						|
                                   const char *s2, int result) {
 | 
						|
  if (!fuzzer::RunningUserCallback) return;
 | 
						|
  if (result == 0) return;  // No reason to mutate.
 | 
						|
  size_t N = fuzzer::InternalStrnlen2(s1, s2);
 | 
						|
  if (N <= 1) return;  // Not interesting.
 | 
						|
  fuzzer::TPC.AddValueForMemcmp(caller_pc, s1, s2, N, /*StopAtZero*/true);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
 | 
						|
void __sanitizer_weak_hook_strncasecmp(void *called_pc, const char *s1,
 | 
						|
                                       const char *s2, size_t n, int result) {
 | 
						|
  if (!fuzzer::RunningUserCallback) return;
 | 
						|
  return __sanitizer_weak_hook_strncmp(called_pc, s1, s2, n, result);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
 | 
						|
void __sanitizer_weak_hook_strcasecmp(void *called_pc, const char *s1,
 | 
						|
                                      const char *s2, int result) {
 | 
						|
  if (!fuzzer::RunningUserCallback) return;
 | 
						|
  return __sanitizer_weak_hook_strcmp(called_pc, s1, s2, result);
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
 | 
						|
void __sanitizer_weak_hook_strstr(void *called_pc, const char *s1,
 | 
						|
                                  const char *s2, char *result) {
 | 
						|
  if (!fuzzer::RunningUserCallback) return;
 | 
						|
  fuzzer::TPC.MMT.Add(reinterpret_cast<const uint8_t *>(s2), strlen(s2));
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
 | 
						|
void __sanitizer_weak_hook_strcasestr(void *called_pc, const char *s1,
 | 
						|
                                      const char *s2, char *result) {
 | 
						|
  if (!fuzzer::RunningUserCallback) return;
 | 
						|
  fuzzer::TPC.MMT.Add(reinterpret_cast<const uint8_t *>(s2), strlen(s2));
 | 
						|
}
 | 
						|
 | 
						|
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
 | 
						|
void __sanitizer_weak_hook_memmem(void *called_pc, const void *s1, size_t len1,
 | 
						|
                                  const void *s2, size_t len2, void *result) {
 | 
						|
  if (!fuzzer::RunningUserCallback) return;
 | 
						|
  fuzzer::TPC.MMT.Add(reinterpret_cast<const uint8_t *>(s2), len2);
 | 
						|
}
 | 
						|
}  // extern "C"
 |