FuzzerTracePC.cpp
22.2 KB
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//===- FuzzerTracePC.cpp - PC tracing--------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
// 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 "FuzzerBuiltins.h"
#include "FuzzerBuiltinsMsvc.h"
#include "FuzzerCorpus.h"
#include "FuzzerDefs.h"
#include "FuzzerDictionary.h"
#include "FuzzerExtFunctions.h"
#include "FuzzerIO.h"
#include "FuzzerUtil.h"
#include "FuzzerValueBitMap.h"
#include <set>
// Used by -fsanitize-coverage=stack-depth to track stack depth
ATTRIBUTES_INTERFACE_TLS_INITIAL_EXEC uintptr_t __sancov_lowest_stack;
namespace fuzzer {
TracePC TPC;
size_t TracePC::GetTotalPCCoverage() {
return ObservedPCs.size();
}
void TracePC::HandleInline8bitCountersInit(uint8_t *Start, uint8_t *Stop) {
if (Start == Stop) return;
if (NumModules &&
Modules[NumModules - 1].Start() == Start)
return;
assert(NumModules <
sizeof(Modules) / sizeof(Modules[0]));
auto &M = Modules[NumModules++];
uint8_t *AlignedStart = RoundUpByPage(Start);
uint8_t *AlignedStop = RoundDownByPage(Stop);
size_t NumFullPages = AlignedStop > AlignedStart ?
(AlignedStop - AlignedStart) / PageSize() : 0;
bool NeedFirst = Start < AlignedStart || !NumFullPages;
bool NeedLast = Stop > AlignedStop && AlignedStop >= AlignedStart;
M.NumRegions = NumFullPages + NeedFirst + NeedLast;;
assert(M.NumRegions > 0);
M.Regions = new Module::Region[M.NumRegions];
assert(M.Regions);
size_t R = 0;
if (NeedFirst)
M.Regions[R++] = {Start, std::min(Stop, AlignedStart), true, false};
for (uint8_t *P = AlignedStart; P < AlignedStop; P += PageSize())
M.Regions[R++] = {P, P + PageSize(), true, true};
if (NeedLast)
M.Regions[R++] = {AlignedStop, Stop, true, false};
assert(R == M.NumRegions);
assert(M.Size() == (size_t)(Stop - Start));
assert(M.Stop() == Stop);
assert(M.Start() == Start);
NumInline8bitCounters += M.Size();
}
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::PrintModuleInfo() {
if (NumModules) {
Printf("INFO: Loaded %zd modules (%zd inline 8-bit counters): ",
NumModules, NumInline8bitCounters);
for (size_t i = 0; i < NumModules; i++)
Printf("%zd [%p, %p), ", Modules[i].Size(), Modules[i].Start(),
Modules[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 (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);
}
/// \return the address of the previous instruction.
/// Note: the logic is copied from `sanitizer_common/sanitizer_stacktrace.h`
inline ALWAYS_INLINE uintptr_t GetPreviousInstructionPc(uintptr_t PC) {
#if defined(__arm__)
// T32 (Thumb) branch instructions might be 16 or 32 bit long,
// so we return (pc-2) in that case in order to be safe.
// For A32 mode we return (pc-4) because all instructions are 32 bit long.
return (PC - 3) & (~1);
#elif defined(__powerpc__) || defined(__powerpc64__) || defined(__aarch64__)
// PCs are always 4 byte aligned.
return PC - 4;
#elif defined(__sparc__) || defined(__mips__)
return PC - 8;
#else
return PC - 1;
#endif
}
/// \return the address of the next instruction.
/// Note: the logic is copied from `sanitizer_common/sanitizer_stacktrace.cpp`
ALWAYS_INLINE uintptr_t TracePC::GetNextInstructionPc(uintptr_t PC) {
#if defined(__mips__)
return PC + 8;
#elif defined(__powerpc__) || defined(__sparc__) || defined(__arm__) || \
defined(__aarch64__)
return PC + 4;
#else
return PC + 1;
#endif
}
void TracePC::UpdateObservedPCs() {
Vector<uintptr_t> CoveredFuncs;
auto ObservePC = [&](const PCTableEntry *TE) {
if (ObservedPCs.insert(TE).second && DoPrintNewPCs) {
PrintPC("\tNEW_PC: %p %F %L", "\tNEW_PC: %p",
GetNextInstructionPc(TE->PC));
Printf("\n");
}
};
auto Observe = [&](const PCTableEntry *TE) {
if (PcIsFuncEntry(TE))
if (++ObservedFuncs[TE->PC] == 1 && NumPrintNewFuncs)
CoveredFuncs.push_back(TE->PC);
ObservePC(TE);
};
if (NumPCsInPCTables) {
if (NumInline8bitCounters == NumPCsInPCTables) {
for (size_t i = 0; i < NumModules; i++) {
auto &M = Modules[i];
assert(M.Size() ==
(size_t)(ModulePCTable[i].Stop - ModulePCTable[i].Start));
for (size_t r = 0; r < M.NumRegions; r++) {
auto &R = M.Regions[r];
if (!R.Enabled) continue;
for (uint8_t *P = R.Start; P < R.Stop; P++)
if (*P)
Observe(&ModulePCTable[i].Start[M.Idx(P)]);
}
}
}
}
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", GetNextInstructionPc(CoveredFuncs[i]));
Printf("\n");
}
}
uintptr_t TracePC::PCTableEntryIdx(const PCTableEntry *TE) {
size_t TotalTEs = 0;
for (size_t i = 0; i < NumPCTables; i++) {
auto &M = ModulePCTable[i];
if (TE >= M.Start && TE < M.Stop)
return TotalTEs + TE - M.Start;
TotalTEs += M.Stop - M.Start;
}
assert(0);
return 0;
}
const TracePC::PCTableEntry *TracePC::PCTableEntryByIdx(uintptr_t Idx) {
for (size_t i = 0; i < NumPCTables; i++) {
auto &M = ModulePCTable[i];
size_t Size = M.Stop - M.Start;
if (Idx < Size) return &M.Start[Idx];
Idx -= Size;
}
return nullptr;
}
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(PcIsFuncEntry(FE) && "Not a function entry point");
do {
NextFE++;
} while (NextFE < M.Stop && !(PcIsFuncEntry(NextFE)));
CB(FE, NextFE, ObservedFuncs[FE->PC]);
}
}
}
void TracePC::SetFocusFunction(const std::string &FuncName) {
// This function should be called once.
assert(!FocusFunctionCounterPtr);
if (FuncName.empty())
return;
for (size_t M = 0; M < NumModules; M++) {
auto &PCTE = ModulePCTable[M];
size_t N = PCTE.Stop - PCTE.Start;
for (size_t I = 0; I < N; I++) {
if (!(PcIsFuncEntry(&PCTE.Start[I]))) 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());
FocusFunctionCounterPtr = Modules[M].Start() + I;
return;
}
}
}
bool TracePC::ObservedFocusFunction() {
return FocusFunctionCounterPtr && *FocusFunctionCounterPtr;
}
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 NumEdges = Last - First;
Vector<uintptr_t> UncoveredPCs;
for (auto TE = First; TE < Last; TE++)
if (!ObservedPCs.count(TE))
UncoveredPCs.push_back(TE->PC);
Printf("%sCOVERED_FUNC: hits: %zd", Counter ? "" : "UN", Counter);
Printf(" edges: %zd/%zd", NumEdges - UncoveredPCs.size(), NumEdges);
Printf(" %s %s:%s\n", FunctionStr.c_str(), FileStr.c_str(),
LineStr.c_str());
if (Counter)
for (auto PC : UncoveredPCs)
Printf(" UNCOVERED_PC: %s\n",
DescribePC("%s:%l", GetNextInstructionPc(PC)).c_str());
};
IterateCoveredFunctions(CoveredFunctionCallback);
}
// 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;
uint8_t HammingDistance = 0;
for (; I < Len; I++) {
if (B1[I] != B2[I] || (StopAtZero && B1[I] == 0)) {
HammingDistance = Popcountll(B1[I] ^ B2[I]);
break;
}
}
size_t PC = reinterpret_cast<size_t>(caller_pc);
size_t Idx = (PC & 4095) | (I << 12);
Idx += HammingDistance;
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 = Popcountll(ArgXor); // [0,64]
uint64_t AbsoluteDistance = (Arg1 == Arg2 ? 0 : 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() {
IterateCounterRegions([](const Module::Region &R){
if (R.Enabled)
memset(R.Start, 0, R.Stop - R.Start);
});
}
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
}
void WarnAboutDeprecatedInstrumentation(const char *flag) {
// Use RawPrint because Printf cannot be used on Windows before OutputFile is
// initialized.
RawPrint(flag);
RawPrint(
" is no longer supported by libFuzzer.\n"
"Please either migrate to a compiler that supports -fsanitize=fuzzer\n"
"or use an older version of libFuzzer\n");
exit(1);
}
} // namespace fuzzer
extern "C" {
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
void __sanitizer_cov_trace_pc_guard(uint32_t *Guard) {
fuzzer::WarnAboutDeprecatedInstrumentation(
"-fsanitize-coverage=trace-pc-guard");
}
// 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() {
fuzzer::WarnAboutDeprecatedInstrumentation("-fsanitize-coverage=trace-pc");
}
ATTRIBUTE_INTERFACE
void __sanitizer_cov_trace_pc_guard_init(uint32_t *Start, uint32_t *Stop) {
fuzzer::WarnAboutDeprecatedInstrumentation(
"-fsanitize-coverage=trace-pc-guard");
}
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>(GET_CALLER_PC());
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>(GET_CALLER_PC());
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>(GET_CALLER_PC());
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>(GET_CALLER_PC());
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>(GET_CALLER_PC());
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>(GET_CALLER_PC());
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>(GET_CALLER_PC());
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>(GET_CALLER_PC());
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>(GET_CALLER_PC());
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: all switch values are small.
// We may want to skip this at compile-time, but it will make the
// instrumentation less general.
if (Vals[N - 1] < 256)
return;
// Also skip small inputs values, they won't give good signal.
if (Val < 256)
return;
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
size_t i;
uint64_t Smaller = 0;
uint64_t Larger = ~(uint64_t)0;
// Find two switch values such that Smaller < Val < Larger.
// Use 0 and 0xfff..f as the defaults.
for (i = 0; i < N; i++) {
if (Val < Vals[i]) {
Larger = Vals[i];
break;
}
if (Val > Vals[i]) Smaller = Vals[i];
}
// Apply HandleCmp to {Val,Smaller} and {Val, Larger},
// use i as the PC modifier for HandleCmp.
if (ValSizeInBits == 16) {
fuzzer::TPC.HandleCmp(PC + 2 * i, static_cast<uint16_t>(Val),
(uint16_t)(Smaller));
fuzzer::TPC.HandleCmp(PC + 2 * i + 1, static_cast<uint16_t>(Val),
(uint16_t)(Larger));
} else if (ValSizeInBits == 32) {
fuzzer::TPC.HandleCmp(PC + 2 * i, static_cast<uint32_t>(Val),
(uint32_t)(Smaller));
fuzzer::TPC.HandleCmp(PC + 2 * i + 1, static_cast<uint32_t>(Val),
(uint32_t)(Larger));
} else {
fuzzer::TPC.HandleCmp(PC + 2*i, Val, Smaller);
fuzzer::TPC.HandleCmp(PC + 2*i + 1, Val, Larger);
}
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
void __sanitizer_cov_trace_div4(uint32_t Val) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
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>(GET_CALLER_PC());
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>(GET_CALLER_PC());
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"