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1//===-- ubsan_handlers.cpp ------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// Error logging entry points for the UBSan runtime.10//11//===----------------------------------------------------------------------===//12 13#include "ubsan_platform.h"14#if CAN_SANITIZE_UB15#include "ubsan_handlers.h"16#include "ubsan_diag.h"17#include "ubsan_flags.h"18#include "ubsan_monitor.h"19#include "ubsan_value.h"20 21#include "sanitizer_common/sanitizer_common.h"22 23using namespace __sanitizer;24using namespace __ubsan;25 26namespace __ubsan {27bool ignoreReport(SourceLocation SLoc, ReportOptions Opts, ErrorType ET) {28  // We are not allowed to skip error report: if we are in unrecoverable29  // handler, we have to terminate the program right now, and therefore30  // have to print some diagnostic.31  //32  // Even if source location is disabled, it doesn't mean that we have33  // already report an error to the user: some concurrently running34  // thread could have acquired it, but not yet printed the report.35  if (Opts.FromUnrecoverableHandler)36    return false;37  return SLoc.isDisabled() || IsPCSuppressed(ET, Opts.pc, SLoc.getFilename());38}39 40/// Situations in which we might emit a check for the suitability of a41/// pointer or glvalue. Needs to be kept in sync with CodeGenFunction.h in42/// clang.43enum TypeCheckKind {44  /// Checking the operand of a load. Must be suitably sized and aligned.45  TCK_Load,46  /// Checking the destination of a store. Must be suitably sized and aligned.47  TCK_Store,48  /// Checking the bound value in a reference binding. Must be suitably sized49  /// and aligned, but is not required to refer to an object (until the50  /// reference is used), per core issue 453.51  TCK_ReferenceBinding,52  /// Checking the object expression in a non-static data member access. Must53  /// be an object within its lifetime.54  TCK_MemberAccess,55  /// Checking the 'this' pointer for a call to a non-static member function.56  /// Must be an object within its lifetime.57  TCK_MemberCall,58  /// Checking the 'this' pointer for a constructor call.59  TCK_ConstructorCall,60  /// Checking the operand of a static_cast to a derived pointer type. Must be61  /// null or an object within its lifetime.62  TCK_DowncastPointer,63  /// Checking the operand of a static_cast to a derived reference type. Must64  /// be an object within its lifetime.65  TCK_DowncastReference,66  /// Checking the operand of a cast to a base object. Must be suitably sized67  /// and aligned.68  TCK_Upcast,69  /// Checking the operand of a cast to a virtual base object. Must be an70  /// object within its lifetime.71  TCK_UpcastToVirtualBase,72  /// Checking the value assigned to a _Nonnull pointer. Must not be null.73  TCK_NonnullAssign,74  /// Checking the operand of a dynamic_cast or a typeid expression.  Must be75  /// null or an object within its lifetime.76  TCK_DynamicOperation77};78 79extern const char *const TypeCheckKinds[] = {80    "load of", "store to", "reference binding to", "member access within",81    "member call on", "constructor call on", "downcast of", "downcast of",82    "upcast of", "cast to virtual base of", "_Nonnull binding to",83    "dynamic operation on"};84}85 86static void handleTypeMismatchImpl(TypeMismatchData *Data, ValueHandle Pointer,87                                   ReportOptions Opts) {88  Location Loc = Data->Loc.acquire();89 90  uptr Alignment = (uptr)1 << Data->LogAlignment;91  ErrorType ET;92  if (!Pointer)93    ET = (Data->TypeCheckKind == TCK_NonnullAssign)94             ? ErrorType::NullPointerUseWithNullability95             : ErrorType::NullPointerUse;96  else if (Pointer & (Alignment - 1))97    ET = ErrorType::MisalignedPointerUse;98  else99    ET = ErrorType::InsufficientObjectSize;100 101  // Use the SourceLocation from Data to track deduplication, even if it's102  // invalid.103  if (ignoreReport(Loc.getSourceLocation(), Opts, ET))104    return;105 106  SymbolizedStackHolder FallbackLoc;107  if (Data->Loc.isInvalid()) {108    FallbackLoc.reset(getCallerLocation(Opts.pc));109    Loc = FallbackLoc;110  }111 112  ScopedReport R(Opts, Loc, ET);113 114  switch (ET) {115  case ErrorType::NullPointerUse:116  case ErrorType::NullPointerUseWithNullability:117    Diag(Loc, DL_Error, ET, "%0 null pointer of type %1")118        << TypeCheckKinds[Data->TypeCheckKind] << Data->Type;119    break;120  case ErrorType::MisalignedPointerUse:121    Diag(Loc, DL_Error, ET, "%0 misaligned address %1 for type %3, "122                        "which requires %2 byte alignment")123        << TypeCheckKinds[Data->TypeCheckKind] << (void *)Pointer << Alignment124        << Data->Type;125    break;126  case ErrorType::InsufficientObjectSize:127    Diag(Loc, DL_Error, ET, "%0 address %1 with insufficient space "128                        "for an object of type %2")129        << TypeCheckKinds[Data->TypeCheckKind] << (void *)Pointer << Data->Type;130    break;131  default:132    UNREACHABLE("unexpected error type!");133  }134 135  if (Pointer)136    Diag(Pointer, DL_Note, ET, "pointer points here");137}138 139void __ubsan::__ubsan_handle_type_mismatch_v1(TypeMismatchData *Data,140                                              ValueHandle Pointer) {141  GET_REPORT_OPTIONS(false);142  handleTypeMismatchImpl(Data, Pointer, Opts);143}144void __ubsan::__ubsan_handle_type_mismatch_v1_abort(TypeMismatchData *Data,145                                                    ValueHandle Pointer) {146  GET_REPORT_OPTIONS(true);147  handleTypeMismatchImpl(Data, Pointer, Opts);148  Die();149}150 151static void handleAlignmentAssumptionImpl(AlignmentAssumptionData *Data,152                                          ValueHandle Pointer,153                                          ValueHandle Alignment,154                                          ValueHandle Offset,155                                          ReportOptions Opts) {156  Location Loc = Data->Loc.acquire();157  SourceLocation AssumptionLoc = Data->AssumptionLoc.acquire();158 159  ErrorType ET = ErrorType::AlignmentAssumption;160 161  if (ignoreReport(Loc.getSourceLocation(), Opts, ET))162    return;163 164  ScopedReport R(Opts, Loc, ET);165 166  uptr RealPointer = Pointer - Offset;167  uptr LSB = LeastSignificantSetBitIndex(RealPointer);168  uptr ActualAlignment = uptr(1) << LSB;169 170  uptr Mask = Alignment - 1;171  uptr MisAlignmentOffset = RealPointer & Mask;172 173  if (!Offset) {174    Diag(Loc, DL_Error, ET,175         "assumption of %0 byte alignment for pointer of type %1 failed")176        << Alignment << Data->Type;177  } else {178    Diag(Loc, DL_Error, ET,179         "assumption of %0 byte alignment (with offset of %1 byte) for pointer "180         "of type %2 failed")181        << Alignment << Offset << Data->Type;182  }183 184  if (!AssumptionLoc.isInvalid())185    Diag(AssumptionLoc, DL_Note, ET, "alignment assumption was specified here");186 187  Diag(RealPointer, DL_Note, ET,188       "%0address is %1 aligned, misalignment offset is %2 bytes")189      << (Offset ? "offset " : "") << ActualAlignment << MisAlignmentOffset;190}191 192void __ubsan::__ubsan_handle_alignment_assumption(AlignmentAssumptionData *Data,193                                                  ValueHandle Pointer,194                                                  ValueHandle Alignment,195                                                  ValueHandle Offset) {196  GET_REPORT_OPTIONS(false);197  handleAlignmentAssumptionImpl(Data, Pointer, Alignment, Offset, Opts);198}199void __ubsan::__ubsan_handle_alignment_assumption_abort(200    AlignmentAssumptionData *Data, ValueHandle Pointer, ValueHandle Alignment,201    ValueHandle Offset) {202  GET_REPORT_OPTIONS(true);203  handleAlignmentAssumptionImpl(Data, Pointer, Alignment, Offset, Opts);204  Die();205}206 207/// \brief Common diagnostic emission for various forms of integer overflow.208template <typename T>209static void handleIntegerOverflowImpl(OverflowData *Data, ValueHandle LHS,210                                      const char *Operator, T RHS,211                                      ReportOptions Opts) {212  SourceLocation Loc = Data->Loc.acquire();213  bool IsSigned = Data->Type.isSignedIntegerTy();214  ErrorType ET = IsSigned ? ErrorType::SignedIntegerOverflow215                          : ErrorType::UnsignedIntegerOverflow;216 217  if (ignoreReport(Loc, Opts, ET))218    return;219 220  // If this is an unsigned overflow in non-fatal mode, potentially ignore it.221  if (!IsSigned && !Opts.FromUnrecoverableHandler &&222      flags()->silence_unsigned_overflow)223    return;224 225  ScopedReport R(Opts, Loc, ET);226 227  Diag(Loc, DL_Error, ET, "%0 integer overflow: "228                          "%1 %2 %3 cannot be represented in type %4")229      << (IsSigned ? "signed" : "unsigned") << Value(Data->Type, LHS)230      << Operator << RHS << Data->Type;231}232 233#define UBSAN_OVERFLOW_HANDLER(handler_name, op, unrecoverable)                \234  void __ubsan::handler_name(OverflowData *Data, ValueHandle LHS,              \235                             ValueHandle RHS) {                                \236    GET_REPORT_OPTIONS(unrecoverable);                                         \237    handleIntegerOverflowImpl(Data, LHS, op, Value(Data->Type, RHS), Opts);    \238    if (unrecoverable)                                                         \239      Die();                                                                   \240  }241 242UBSAN_OVERFLOW_HANDLER(__ubsan_handle_add_overflow, "+", false)243UBSAN_OVERFLOW_HANDLER(__ubsan_handle_add_overflow_abort, "+", true)244UBSAN_OVERFLOW_HANDLER(__ubsan_handle_sub_overflow, "-", false)245UBSAN_OVERFLOW_HANDLER(__ubsan_handle_sub_overflow_abort, "-", true)246UBSAN_OVERFLOW_HANDLER(__ubsan_handle_mul_overflow, "*", false)247UBSAN_OVERFLOW_HANDLER(__ubsan_handle_mul_overflow_abort, "*", true)248 249static void handleNegateOverflowImpl(OverflowData *Data, ValueHandle OldVal,250                                     ReportOptions Opts) {251  SourceLocation Loc = Data->Loc.acquire();252  bool IsSigned = Data->Type.isSignedIntegerTy();253  ErrorType ET = IsSigned ? ErrorType::SignedIntegerOverflow254                          : ErrorType::UnsignedIntegerOverflow;255 256  if (ignoreReport(Loc, Opts, ET))257    return;258 259  if (!IsSigned && flags()->silence_unsigned_overflow)260    return;261 262  ScopedReport R(Opts, Loc, ET);263 264  if (IsSigned)265    Diag(Loc, DL_Error, ET,266         "negation of %0 cannot be represented in type %1; "267         "cast to an unsigned type to negate this value to itself")268        << Value(Data->Type, OldVal) << Data->Type;269  else270    Diag(Loc, DL_Error, ET, "negation of %0 cannot be represented in type %1")271        << Value(Data->Type, OldVal) << Data->Type;272}273 274void __ubsan::__ubsan_handle_negate_overflow(OverflowData *Data,275                                             ValueHandle OldVal) {276  GET_REPORT_OPTIONS(false);277  handleNegateOverflowImpl(Data, OldVal, Opts);278}279void __ubsan::__ubsan_handle_negate_overflow_abort(OverflowData *Data,280                                                    ValueHandle OldVal) {281  GET_REPORT_OPTIONS(true);282  handleNegateOverflowImpl(Data, OldVal, Opts);283  Die();284}285 286static void handleDivremOverflowImpl(OverflowData *Data, ValueHandle LHS,287                                     ValueHandle RHS, ReportOptions Opts) {288  SourceLocation Loc = Data->Loc.acquire();289  Value LHSVal(Data->Type, LHS);290  Value RHSVal(Data->Type, RHS);291 292  ErrorType ET;293  if (RHSVal.isMinusOne())294    ET = ErrorType::SignedIntegerOverflow;295  else if (Data->Type.isIntegerTy())296    ET = ErrorType::IntegerDivideByZero;297  else298    ET = ErrorType::FloatDivideByZero;299 300  if (ignoreReport(Loc, Opts, ET))301    return;302 303  ScopedReport R(Opts, Loc, ET);304 305  switch (ET) {306  case ErrorType::SignedIntegerOverflow:307    Diag(Loc, DL_Error, ET,308         "division of %0 by -1 cannot be represented in type %1")309        << LHSVal << Data->Type;310    break;311  default:312    Diag(Loc, DL_Error, ET, "division by zero");313    break;314  }315}316 317void __ubsan::__ubsan_handle_divrem_overflow(OverflowData *Data,318                                             ValueHandle LHS, ValueHandle RHS) {319  GET_REPORT_OPTIONS(false);320  handleDivremOverflowImpl(Data, LHS, RHS, Opts);321}322void __ubsan::__ubsan_handle_divrem_overflow_abort(OverflowData *Data,323                                                    ValueHandle LHS,324                                                    ValueHandle RHS) {325  GET_REPORT_OPTIONS(true);326  handleDivremOverflowImpl(Data, LHS, RHS, Opts);327  Die();328}329 330static void handleShiftOutOfBoundsImpl(ShiftOutOfBoundsData *Data,331                                       ValueHandle LHS, ValueHandle RHS,332                                       ReportOptions Opts) {333  SourceLocation Loc = Data->Loc.acquire();334  Value LHSVal(Data->LHSType, LHS);335  Value RHSVal(Data->RHSType, RHS);336 337  ErrorType ET;338  if (RHSVal.isNegative() ||339      RHSVal.getPositiveIntValue() >= Data->LHSType.getIntegerBitWidth())340    ET = ErrorType::InvalidShiftExponent;341  else342    ET = ErrorType::InvalidShiftBase;343 344  if (ignoreReport(Loc, Opts, ET))345    return;346 347  ScopedReport R(Opts, Loc, ET);348 349  if (ET == ErrorType::InvalidShiftExponent) {350    if (RHSVal.isNegative())351      Diag(Loc, DL_Error, ET, "shift exponent %0 is negative") << RHSVal;352    else353      Diag(Loc, DL_Error, ET,354           "shift exponent %0 is too large for %1-bit type %2")355          << RHSVal << Data->LHSType.getIntegerBitWidth() << Data->LHSType;356  } else {357    if (LHSVal.isNegative())358      Diag(Loc, DL_Error, ET, "left shift of negative value %0") << LHSVal;359    else360      Diag(Loc, DL_Error, ET,361           "left shift of %0 by %1 places cannot be represented in type %2")362          << LHSVal << RHSVal << Data->LHSType;363  }364}365 366void __ubsan::__ubsan_handle_shift_out_of_bounds(ShiftOutOfBoundsData *Data,367                                                 ValueHandle LHS,368                                                 ValueHandle RHS) {369  GET_REPORT_OPTIONS(false);370  handleShiftOutOfBoundsImpl(Data, LHS, RHS, Opts);371}372void __ubsan::__ubsan_handle_shift_out_of_bounds_abort(373                                                     ShiftOutOfBoundsData *Data,374                                                     ValueHandle LHS,375                                                     ValueHandle RHS) {376  GET_REPORT_OPTIONS(true);377  handleShiftOutOfBoundsImpl(Data, LHS, RHS, Opts);378  Die();379}380 381static void handleOutOfBoundsImpl(OutOfBoundsData *Data, ValueHandle Index,382                                  ReportOptions Opts) {383  SourceLocation Loc = Data->Loc.acquire();384  ErrorType ET = ErrorType::OutOfBoundsIndex;385 386  if (ignoreReport(Loc, Opts, ET))387    return;388 389  ScopedReport R(Opts, Loc, ET);390 391  Value IndexVal(Data->IndexType, Index);392  Diag(Loc, DL_Error, ET, "index %0 out of bounds for type %1")393    << IndexVal << Data->ArrayType;394}395 396void __ubsan::__ubsan_handle_out_of_bounds(OutOfBoundsData *Data,397                                           ValueHandle Index) {398  GET_REPORT_OPTIONS(false);399  handleOutOfBoundsImpl(Data, Index, Opts);400}401void __ubsan::__ubsan_handle_out_of_bounds_abort(OutOfBoundsData *Data,402                                                 ValueHandle Index) {403  GET_REPORT_OPTIONS(true);404  handleOutOfBoundsImpl(Data, Index, Opts);405  Die();406}407 408static void handleLocalOutOfBoundsImpl(ReportOptions Opts) {409  // FIXME: Pass more diagnostic info.410  SymbolizedStackHolder CallerLoc;411  CallerLoc.reset(getCallerLocation(Opts.pc));412  Location Loc;413  Loc = CallerLoc;414  ErrorType ET = ErrorType::LocalOutOfBounds;415  ScopedReport R(Opts, Loc, ET);416  Diag(Loc, DL_Error, ET, "access out of bounds");417}418 419void __ubsan::__ubsan_handle_local_out_of_bounds() {420  GET_REPORT_OPTIONS(false);421  handleLocalOutOfBoundsImpl(Opts);422}423 424void __ubsan::__ubsan_handle_local_out_of_bounds_abort() {425  GET_REPORT_OPTIONS(true);426  handleLocalOutOfBoundsImpl(Opts);427  Die();428}429 430static void handleBuiltinUnreachableImpl(UnreachableData *Data,431                                         ReportOptions Opts) {432  ErrorType ET = ErrorType::UnreachableCall;433  ScopedReport R(Opts, Data->Loc, ET);434  Diag(Data->Loc, DL_Error, ET,435       "execution reached an unreachable program point");436}437 438void __ubsan::__ubsan_handle_builtin_unreachable(UnreachableData *Data) {439  GET_REPORT_OPTIONS(true);440  handleBuiltinUnreachableImpl(Data, Opts);441  Die();442}443 444static void handleMissingReturnImpl(UnreachableData *Data, ReportOptions Opts) {445  ErrorType ET = ErrorType::MissingReturn;446  ScopedReport R(Opts, Data->Loc, ET);447  Diag(Data->Loc, DL_Error, ET,448       "execution reached the end of a value-returning function "449       "without returning a value");450}451 452void __ubsan::__ubsan_handle_missing_return(UnreachableData *Data) {453  GET_REPORT_OPTIONS(true);454  handleMissingReturnImpl(Data, Opts);455  Die();456}457 458static void handleVLABoundNotPositive(VLABoundData *Data, ValueHandle Bound,459                                      ReportOptions Opts) {460  SourceLocation Loc = Data->Loc.acquire();461  ErrorType ET = ErrorType::NonPositiveVLAIndex;462 463  if (ignoreReport(Loc, Opts, ET))464    return;465 466  ScopedReport R(Opts, Loc, ET);467 468  Diag(Loc, DL_Error, ET, "variable length array bound evaluates to "469                          "non-positive value %0")470      << Value(Data->Type, Bound);471}472 473void __ubsan::__ubsan_handle_vla_bound_not_positive(VLABoundData *Data,474                                                    ValueHandle Bound) {475  GET_REPORT_OPTIONS(false);476  handleVLABoundNotPositive(Data, Bound, Opts);477}478void __ubsan::__ubsan_handle_vla_bound_not_positive_abort(VLABoundData *Data,479                                                          ValueHandle Bound) {480  GET_REPORT_OPTIONS(true);481  handleVLABoundNotPositive(Data, Bound, Opts);482  Die();483}484 485static bool looksLikeFloatCastOverflowDataV1(void *Data) {486  // First field is either a pointer to filename or a pointer to a487  // TypeDescriptor.488  u8 *FilenameOrTypeDescriptor;489  internal_memcpy(&FilenameOrTypeDescriptor, Data,490                  sizeof(FilenameOrTypeDescriptor));491 492  // Heuristic: For float_cast_overflow, the TypeKind will be either TK_Integer493  // (0x0), TK_Float (0x1) or TK_Unknown (0xff). If both types are known,494  // adding both bytes will be 0 or 1 (for BE or LE). If it were a filename,495  // adding two printable characters will not yield such a value. Otherwise,496  // if one of them is 0xff, this is most likely TK_Unknown type descriptor.497  u16 MaybeFromTypeKind =498      FilenameOrTypeDescriptor[0] + FilenameOrTypeDescriptor[1];499  return MaybeFromTypeKind < 2 || FilenameOrTypeDescriptor[0] == 0xff ||500         FilenameOrTypeDescriptor[1] == 0xff;501}502 503static void handleFloatCastOverflow(void *DataPtr, ValueHandle From,504                                    ReportOptions Opts) {505  SymbolizedStackHolder CallerLoc;506  Location Loc;507  const TypeDescriptor *FromType, *ToType;508  ErrorType ET = ErrorType::FloatCastOverflow;509 510  if (looksLikeFloatCastOverflowDataV1(DataPtr)) {511    auto Data = reinterpret_cast<FloatCastOverflowData *>(DataPtr);512    CallerLoc.reset(getCallerLocation(Opts.pc));513    Loc = CallerLoc;514    FromType = &Data->FromType;515    ToType = &Data->ToType;516  } else {517    auto Data = reinterpret_cast<FloatCastOverflowDataV2 *>(DataPtr);518    SourceLocation SLoc = Data->Loc.acquire();519    if (ignoreReport(SLoc, Opts, ET))520      return;521    Loc = SLoc;522    FromType = &Data->FromType;523    ToType = &Data->ToType;524  }525 526  ScopedReport R(Opts, Loc, ET);527 528  Diag(Loc, DL_Error, ET,529       "%0 is outside the range of representable values of type %2")530      << Value(*FromType, From) << *FromType << *ToType;531}532 533void __ubsan::__ubsan_handle_float_cast_overflow(void *Data, ValueHandle From) {534  GET_REPORT_OPTIONS(false);535  handleFloatCastOverflow(Data, From, Opts);536}537void __ubsan::__ubsan_handle_float_cast_overflow_abort(void *Data,538                                                       ValueHandle From) {539  GET_REPORT_OPTIONS(true);540  handleFloatCastOverflow(Data, From, Opts);541  Die();542}543 544static void handleLoadInvalidValue(InvalidValueData *Data, ValueHandle Val,545                                   ReportOptions Opts) {546  SourceLocation Loc = Data->Loc.acquire();547  // This check could be more precise if we used different handlers for548  // -fsanitize=bool and -fsanitize=enum.549  bool IsBool = (0 == internal_strcmp(Data->Type.getTypeName(), "'bool'")) ||550                (0 == internal_strncmp(Data->Type.getTypeName(), "'BOOL'", 6));551  ErrorType ET =552      IsBool ? ErrorType::InvalidBoolLoad : ErrorType::InvalidEnumLoad;553 554  if (ignoreReport(Loc, Opts, ET))555    return;556 557  ScopedReport R(Opts, Loc, ET);558 559  Diag(Loc, DL_Error, ET,560       "load of value %0, which is not a valid value for type %1")561      << Value(Data->Type, Val) << Data->Type;562}563 564void __ubsan::__ubsan_handle_load_invalid_value(InvalidValueData *Data,565                                                ValueHandle Val) {566  GET_REPORT_OPTIONS(false);567  handleLoadInvalidValue(Data, Val, Opts);568}569void __ubsan::__ubsan_handle_load_invalid_value_abort(InvalidValueData *Data,570                                                      ValueHandle Val) {571  GET_REPORT_OPTIONS(true);572  handleLoadInvalidValue(Data, Val, Opts);573  Die();574}575 576static void handleImplicitConversion(ImplicitConversionData *Data,577                                     ReportOptions Opts, ValueHandle Src,578                                     ValueHandle Dst) {579  SourceLocation Loc = Data->Loc.acquire();580  const TypeDescriptor &SrcTy = Data->FromType;581  const TypeDescriptor &DstTy = Data->ToType;582  bool SrcSigned = SrcTy.isSignedIntegerTy();583  bool DstSigned = DstTy.isSignedIntegerTy();584  ErrorType ET = ErrorType::GenericUB;585 586  switch (Data->Kind) {587  case ICCK_IntegerTruncation: { // Legacy, no longer used.588    // Let's figure out what it should be as per the new types, and upgrade.589    // If both types are unsigned, then it's an unsigned truncation.590    // Else, it is a signed truncation.591    if (!SrcSigned && !DstSigned) {592      ET = ErrorType::ImplicitUnsignedIntegerTruncation;593    } else {594      ET = ErrorType::ImplicitSignedIntegerTruncation;595    }596    break;597  }598  case ICCK_UnsignedIntegerTruncation:599    ET = ErrorType::ImplicitUnsignedIntegerTruncation;600    break;601  case ICCK_SignedIntegerTruncation:602    ET = ErrorType::ImplicitSignedIntegerTruncation;603    break;604  case ICCK_IntegerSignChange:605    ET = ErrorType::ImplicitIntegerSignChange;606    break;607  case ICCK_SignedIntegerTruncationOrSignChange:608    ET = ErrorType::ImplicitSignedIntegerTruncationOrSignChange;609    break;610  }611 612  if (ignoreReport(Loc, Opts, ET))613    return;614 615  ScopedReport R(Opts, Loc, ET);616 617  // In the case we have a bitfield, we want to explicitly say so in the618  // error message.619  // FIXME: is it possible to dump the values as hex with fixed width?620  if (Data->BitfieldBits)621    Diag(Loc, DL_Error, ET,622         "implicit conversion from type %0 of value %1 (%2-bit, %3signed) to "623         "type %4 changed the value to %5 (%6-bit bitfield, %7signed)")624        << SrcTy << Value(SrcTy, Src) << SrcTy.getIntegerBitWidth()625        << (SrcSigned ? "" : "un") << DstTy << Value(DstTy, Dst)626        << Data->BitfieldBits << (DstSigned ? "" : "un");627  else628    Diag(Loc, DL_Error, ET,629         "implicit conversion from type %0 of value %1 (%2-bit, %3signed) to "630         "type %4 changed the value to %5 (%6-bit, %7signed)")631        << SrcTy << Value(SrcTy, Src) << SrcTy.getIntegerBitWidth()632        << (SrcSigned ? "" : "un") << DstTy << Value(DstTy, Dst)633        << DstTy.getIntegerBitWidth() << (DstSigned ? "" : "un");634}635 636void __ubsan::__ubsan_handle_implicit_conversion(ImplicitConversionData *Data,637                                                 ValueHandle Src,638                                                 ValueHandle Dst) {639  GET_REPORT_OPTIONS(false);640  handleImplicitConversion(Data, Opts, Src, Dst);641}642void __ubsan::__ubsan_handle_implicit_conversion_abort(643    ImplicitConversionData *Data, ValueHandle Src, ValueHandle Dst) {644  GET_REPORT_OPTIONS(true);645  handleImplicitConversion(Data, Opts, Src, Dst);646  Die();647}648 649static void handleInvalidBuiltin(InvalidBuiltinData *Data, ReportOptions Opts) {650  SourceLocation Loc = Data->Loc.acquire();651  ErrorType ET = ErrorType::InvalidBuiltin;652 653  if (ignoreReport(Loc, Opts, ET))654    return;655 656  ScopedReport R(Opts, Loc, ET);657 658  if (Data->Kind == BCK_AssumePassedFalse)659    Diag(Loc, DL_Error, ET, "assumption is violated during execution");660  else661    Diag(Loc, DL_Error, ET,662         "passing zero to __builtin_%0(), which is not a valid argument")663        << ((Data->Kind == BCK_CTZPassedZero) ? "ctz" : "clz");664}665 666void __ubsan::__ubsan_handle_invalid_builtin(InvalidBuiltinData *Data) {667  GET_REPORT_OPTIONS(false);668  handleInvalidBuiltin(Data, Opts);669}670void __ubsan::__ubsan_handle_invalid_builtin_abort(InvalidBuiltinData *Data) {671  GET_REPORT_OPTIONS(true);672  handleInvalidBuiltin(Data, Opts);673  Die();674}675 676static void handleInvalidObjCCast(InvalidObjCCast *Data, ValueHandle Pointer,677                                  ReportOptions Opts) {678  SourceLocation Loc = Data->Loc.acquire();679  ErrorType ET = ErrorType::InvalidObjCCast;680 681  if (ignoreReport(Loc, Opts, ET))682    return;683 684  ScopedReport R(Opts, Loc, ET);685 686  const char *GivenClass = getObjCClassName(Pointer);687  const char *GivenClassStr = GivenClass ? GivenClass : "<unknown type>";688 689  Diag(Loc, DL_Error, ET,690       "invalid ObjC cast, object is a '%0', but expected a %1")691      << GivenClassStr << Data->ExpectedType;692}693 694void __ubsan::__ubsan_handle_invalid_objc_cast(InvalidObjCCast *Data,695                                               ValueHandle Pointer) {696  GET_REPORT_OPTIONS(false);697  handleInvalidObjCCast(Data, Pointer, Opts);698}699void __ubsan::__ubsan_handle_invalid_objc_cast_abort(InvalidObjCCast *Data,700                                                     ValueHandle Pointer) {701  GET_REPORT_OPTIONS(true);702  handleInvalidObjCCast(Data, Pointer, Opts);703  Die();704}705 706static void handleNonNullReturn(NonNullReturnData *Data, SourceLocation *LocPtr,707                                ReportOptions Opts, bool IsAttr) {708  if (!LocPtr)709    UNREACHABLE("source location pointer is null!");710 711  SourceLocation Loc = LocPtr->acquire();712  ErrorType ET = IsAttr ? ErrorType::InvalidNullReturn713                        : ErrorType::InvalidNullReturnWithNullability;714 715  if (ignoreReport(Loc, Opts, ET))716    return;717 718  ScopedReport R(Opts, Loc, ET);719 720  Diag(Loc, DL_Error, ET,721       "null pointer returned from function declared to never return null");722  if (!Data->AttrLoc.isInvalid())723    Diag(Data->AttrLoc, DL_Note, ET, "%0 specified here")724        << (IsAttr ? "returns_nonnull attribute"725                   : "_Nonnull return type annotation");726}727 728void __ubsan::__ubsan_handle_nonnull_return_v1(NonNullReturnData *Data,729                                               SourceLocation *LocPtr) {730  GET_REPORT_OPTIONS(false);731  handleNonNullReturn(Data, LocPtr, Opts, true);732}733 734void __ubsan::__ubsan_handle_nonnull_return_v1_abort(NonNullReturnData *Data,735                                                     SourceLocation *LocPtr) {736  GET_REPORT_OPTIONS(true);737  handleNonNullReturn(Data, LocPtr, Opts, true);738  Die();739}740 741void __ubsan::__ubsan_handle_nullability_return_v1(NonNullReturnData *Data,742                                                   SourceLocation *LocPtr) {743  GET_REPORT_OPTIONS(false);744  handleNonNullReturn(Data, LocPtr, Opts, false);745}746 747void __ubsan::__ubsan_handle_nullability_return_v1_abort(748    NonNullReturnData *Data, SourceLocation *LocPtr) {749  GET_REPORT_OPTIONS(true);750  handleNonNullReturn(Data, LocPtr, Opts, false);751  Die();752}753 754static void handleNonNullArg(NonNullArgData *Data, ReportOptions Opts,755                             bool IsAttr) {756  SourceLocation Loc = Data->Loc.acquire();757  ErrorType ET = IsAttr ? ErrorType::InvalidNullArgument758                        : ErrorType::InvalidNullArgumentWithNullability;759 760  if (ignoreReport(Loc, Opts, ET))761    return;762 763  ScopedReport R(Opts, Loc, ET);764 765  Diag(Loc, DL_Error, ET,766       "null pointer passed as argument %0, which is declared to "767       "never be null")768      << Data->ArgIndex;769  if (!Data->AttrLoc.isInvalid())770    Diag(Data->AttrLoc, DL_Note, ET, "%0 specified here")771        << (IsAttr ? "nonnull attribute" : "_Nonnull type annotation");772}773 774void __ubsan::__ubsan_handle_nonnull_arg(NonNullArgData *Data) {775  GET_REPORT_OPTIONS(false);776  handleNonNullArg(Data, Opts, true);777}778 779void __ubsan::__ubsan_handle_nonnull_arg_abort(NonNullArgData *Data) {780  GET_REPORT_OPTIONS(true);781  handleNonNullArg(Data, Opts, true);782  Die();783}784 785void __ubsan::__ubsan_handle_nullability_arg(NonNullArgData *Data) {786  GET_REPORT_OPTIONS(false);787  handleNonNullArg(Data, Opts, false);788}789 790void __ubsan::__ubsan_handle_nullability_arg_abort(NonNullArgData *Data) {791  GET_REPORT_OPTIONS(true);792  handleNonNullArg(Data, Opts, false);793  Die();794}795 796static void handlePointerOverflowImpl(PointerOverflowData *Data,797                                      ValueHandle Base,798                                      ValueHandle Result,799                                      ReportOptions Opts) {800  SourceLocation Loc = Data->Loc.acquire();801  ErrorType ET;802 803  if (Base == 0 && Result == 0)804    ET = ErrorType::NullptrWithOffset;805  else if (Base == 0 && Result != 0)806    ET = ErrorType::NullptrWithNonZeroOffset;807  else if (Base != 0 && Result == 0)808    ET = ErrorType::NullptrAfterNonZeroOffset;809  else810    ET = ErrorType::PointerOverflow;811 812  if (ignoreReport(Loc, Opts, ET))813    return;814 815  ScopedReport R(Opts, Loc, ET);816 817  if (ET == ErrorType::NullptrWithOffset) {818    Diag(Loc, DL_Error, ET, "applying zero offset to null pointer");819  } else if (ET == ErrorType::NullptrWithNonZeroOffset) {820    Diag(Loc, DL_Error, ET, "applying non-zero offset %0 to null pointer")821        << Result;822  } else if (ET == ErrorType::NullptrAfterNonZeroOffset) {823    Diag(824        Loc, DL_Error, ET,825        "applying non-zero offset to non-null pointer %0 produced null pointer")826        << (void *)Base;827  } else if ((sptr(Base) >= 0) == (sptr(Result) >= 0)) {828    if (Base > Result)829      Diag(Loc, DL_Error, ET,830           "addition of unsigned offset to %0 overflowed to %1")831          << (void *)Base << (void *)Result;832    else833      Diag(Loc, DL_Error, ET,834           "subtraction of unsigned offset from %0 overflowed to %1")835          << (void *)Base << (void *)Result;836  } else {837    Diag(Loc, DL_Error, ET,838         "pointer index expression with base %0 overflowed to %1")839        << (void *)Base << (void *)Result;840  }841}842 843void __ubsan::__ubsan_handle_pointer_overflow(PointerOverflowData *Data,844                                              ValueHandle Base,845                                              ValueHandle Result) {846  GET_REPORT_OPTIONS(false);847  handlePointerOverflowImpl(Data, Base, Result, Opts);848}849 850void __ubsan::__ubsan_handle_pointer_overflow_abort(PointerOverflowData *Data,851                                                    ValueHandle Base,852                                                    ValueHandle Result) {853  GET_REPORT_OPTIONS(true);854  handlePointerOverflowImpl(Data, Base, Result, Opts);855  Die();856}857 858static void handleCFIBadIcall(CFICheckFailData *Data, ValueHandle Function,859                              ReportOptions Opts) {860  if (Data->CheckKind != CFITCK_ICall && Data->CheckKind != CFITCK_NVMFCall)861    Die();862 863  SourceLocation Loc = Data->Loc.acquire();864  ErrorType ET = ErrorType::CFIBadType;865 866  if (ignoreReport(Loc, Opts, ET))867    return;868 869  ScopedReport R(Opts, Loc, ET);870 871  const char *CheckKindStr = Data->CheckKind == CFITCK_NVMFCall872                                 ? "non-virtual pointer to member function call"873                                 : "indirect function call";874  Diag(Loc, DL_Error, ET,875       "control flow integrity check for type %0 failed during %1")876      << Data->Type << CheckKindStr;877 878  SymbolizedStackHolder FLoc(getSymbolizedLocation(Function));879  const char *FName = FLoc.get()->info.function;880  if (!FName)881    FName = "(unknown)";882  Diag(FLoc, DL_Note, ET, "%0 defined here") << FName;883 884  // If the failure involved different DSOs for the check location and icall885  // target, report the DSO names.886  const char *DstModule = FLoc.get()->info.module;887  if (!DstModule)888    DstModule = "(unknown)";889 890  const char *SrcModule = Symbolizer::GetOrInit()->GetModuleNameForPc(Opts.pc);891  if (!SrcModule)892    SrcModule = "(unknown)";893 894  if (internal_strcmp(SrcModule, DstModule))895    Diag(Loc, DL_Note, ET,896         "check failed in %0, destination function located in %1")897        << SrcModule << DstModule;898}899 900namespace __ubsan {901 902#ifdef _WIN32903extern "C" void __ubsan_handle_cfi_bad_type_default(CFICheckFailData *Data,904                                                    ValueHandle Vtable,905                                                    bool ValidVtable,906                                                    ReportOptions Opts) {907  Die();908}909 910WIN_WEAK_ALIAS(__ubsan_handle_cfi_bad_type, __ubsan_handle_cfi_bad_type_default)911void __ubsan_handle_cfi_bad_type(CFICheckFailData *Data, ValueHandle Vtable,912                                 bool ValidVtable, ReportOptions Opts);913#else914SANITIZER_WEAK_ATTRIBUTE915void __ubsan_handle_cfi_bad_type(CFICheckFailData *Data, ValueHandle Vtable,916                                 bool ValidVtable, ReportOptions Opts) {917  Die();918}919#endif920 921} // namespace __ubsan922 923void __ubsan::__ubsan_handle_cfi_check_fail(CFICheckFailData *Data,924                                            ValueHandle Value,925                                            uptr ValidVtable) {926  GET_REPORT_OPTIONS(false);927  if (Data->CheckKind == CFITCK_ICall || Data->CheckKind == CFITCK_NVMFCall)928    handleCFIBadIcall(Data, Value, Opts);929  else930    __ubsan_handle_cfi_bad_type(Data, Value, ValidVtable, Opts);931}932 933void __ubsan::__ubsan_handle_cfi_check_fail_abort(CFICheckFailData *Data,934                                                  ValueHandle Value,935                                                  uptr ValidVtable) {936  GET_REPORT_OPTIONS(true);937  if (Data->CheckKind == CFITCK_ICall || Data->CheckKind == CFITCK_NVMFCall)938    handleCFIBadIcall(Data, Value, Opts);939  else940    __ubsan_handle_cfi_bad_type(Data, Value, ValidVtable, Opts);941  Die();942}943 944static bool handleFunctionTypeMismatch(FunctionTypeMismatchData *Data,945                                       ValueHandle Function,946                                       ReportOptions Opts) {947  SourceLocation CallLoc = Data->Loc.acquire();948  ErrorType ET = ErrorType::FunctionTypeMismatch;949  if (ignoreReport(CallLoc, Opts, ET))950    return true;951 952  ScopedReport R(Opts, CallLoc, ET);953 954  SymbolizedStackHolder FLoc(getSymbolizedLocation(Function));955  const char *FName = FLoc.get()->info.function;956  if (!FName)957    FName = "(unknown)";958 959  Diag(CallLoc, DL_Error, ET,960       "call to function %0 through pointer to incorrect function type %1")961      << FName << Data->Type;962  Diag(FLoc, DL_Note, ET, "%0 defined here") << FName;963  return true;964}965 966void __ubsan::__ubsan_handle_function_type_mismatch(967    FunctionTypeMismatchData *Data, ValueHandle Function) {968  GET_REPORT_OPTIONS(false);969  handleFunctionTypeMismatch(Data, Function, Opts);970}971 972void __ubsan::__ubsan_handle_function_type_mismatch_abort(973    FunctionTypeMismatchData *Data, ValueHandle Function) {974  GET_REPORT_OPTIONS(true);975  if (handleFunctionTypeMismatch(Data, Function, Opts))976    Die();977}978 979#endif  // CAN_SANITIZE_UB980