contrib/llvm/tools/clang/lib/Driver/SanitizerArgs.cpp

   1 //===--- SanitizerArgs.cpp - Arguments for sanitizer tools  ---------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 #include "clang/Driver/SanitizerArgs.h"
  10 #include "ToolChains/CommonArgs.h"
  11 #include "clang/Basic/Sanitizers.h"
  12 #include "clang/Driver/Driver.h"
  13 #include "clang/Driver/DriverDiagnostic.h"
  14 #include "clang/Driver/Options.h"
  15 #include "clang/Driver/ToolChain.h"
  16 #include "llvm/ADT/StringExtras.h"
  17 #include "llvm/ADT/StringSwitch.h"
  18 #include "llvm/Support/FileSystem.h"
  19 #include "llvm/Support/Path.h"
  20 #include "llvm/Support/SpecialCaseList.h"
  21 #include <memory>
  22
  23 using namespace clang;
  24 using namespace clang::SanitizerKind;
  25 using namespace clang::driver;
  26 using namespace llvm::opt;
  27
  28 enum : SanitizerMask {
  29   NeedsUbsanRt = Undefined | Integer | Nullability | CFI,
  30   NeedsUbsanCxxRt = Vptr | CFI,
  31   NotAllowedWithTrap = Vptr,
  32   NotAllowedWithMinimalRuntime = Vptr,
  33   RequiresPIE = DataFlow | Scudo,
  34   NeedsUnwindTables = Address | HWAddress | Thread | Memory | DataFlow,
  35   SupportsCoverage = Address | HWAddress | KernelAddress | Memory | Leak |
  36                      Undefined | Integer | Nullability | DataFlow | Fuzzer |
  37                      FuzzerNoLink,
  38   RecoverableByDefault = Undefined | Integer | Nullability,
  39   Unrecoverable = Unreachable | Return,
  40   LegacyFsanitizeRecoverMask = Undefined | Integer,
  41   NeedsLTO = CFI,
  42   TrappingSupported = (Undefined & ~Vptr) | UnsignedIntegerOverflow |
  43                       Nullability | LocalBounds | CFI,
  44   TrappingDefault = CFI,
  45   CFIClasses = CFIVCall | CFINVCall | CFIDerivedCast | CFIUnrelatedCast,
  46   CompatibleWithMinimalRuntime = TrappingSupported,
  47 };
  48
  49 enum CoverageFeature {
  50   CoverageFunc = 1 << 0,
  51   CoverageBB = 1 << 1,
  52   CoverageEdge = 1 << 2,
  53   CoverageIndirCall = 1 << 3,
  54   CoverageTraceBB = 1 << 4,  // Deprecated.
  55   CoverageTraceCmp = 1 << 5,
  56   CoverageTraceDiv = 1 << 6,
  57   CoverageTraceGep = 1 << 7,
  58   Coverage8bitCounters = 1 << 8,  // Deprecated.
  59   CoverageTracePC = 1 << 9,
  60   CoverageTracePCGuard = 1 << 10,
  61   CoverageNoPrune = 1 << 11,
  62   CoverageInline8bitCounters = 1 << 12,
  63   CoveragePCTable = 1 << 13,
  64   CoverageStackDepth = 1 << 14,
  65 };
  66
  67 /// Parse a -fsanitize= or -fno-sanitize= argument's values, diagnosing any
  68 /// invalid components. Returns a SanitizerMask.
  69 static SanitizerMask parseArgValues(const Driver &D, const llvm::opt::Arg *A,
  70                                     bool DiagnoseErrors);
  71
  72 /// Parse -f(no-)?sanitize-coverage= flag values, diagnosing any invalid
  73 /// components. Returns OR of members of \c CoverageFeature enumeration.
  74 static int parseCoverageFeatures(const Driver &D, const llvm::opt::Arg *A);
  75
  76 /// Produce an argument string from ArgList \p Args, which shows how it
  77 /// provides some sanitizer kind from \p Mask. For example, the argument list
  78 /// "-fsanitize=thread,vptr -fsanitize=address" with mask \c NeedsUbsanRt
  79 /// would produce "-fsanitize=vptr".
  80 static std::string lastArgumentForMask(const Driver &D,
  81                                        const llvm::opt::ArgList &Args,
  82                                        SanitizerMask Mask);
  83
  84 /// Produce an argument string from argument \p A, which shows how it provides
  85 /// a value in \p Mask. For instance, the argument
  86 /// "-fsanitize=address,alignment" with mask \c NeedsUbsanRt would produce
  87 /// "-fsanitize=alignment".
  88 static std::string describeSanitizeArg(const llvm::opt::Arg *A,
  89                                        SanitizerMask Mask);
  90
  91 /// Produce a string containing comma-separated names of sanitizers in \p
  92 /// Sanitizers set.
  93 static std::string toString(const clang::SanitizerSet &Sanitizers);
  94
  95 static bool getDefaultBlacklist(const Driver &D, SanitizerMask Kinds,
  96                                 std::string &BLPath) {
  97   const char *BlacklistFile = nullptr;
  98   if (Kinds & Address)
  99     BlacklistFile = "asan_blacklist.txt";
 100   else if (Kinds & HWAddress)
 101     BlacklistFile = "hwasan_blacklist.txt";
 102   else if (Kinds & Memory)
 103     BlacklistFile = "msan_blacklist.txt";
 104   else if (Kinds & Thread)
 105     BlacklistFile = "tsan_blacklist.txt";
 106   else if (Kinds & DataFlow)
 107     BlacklistFile = "dfsan_abilist.txt";
 108   else if (Kinds & CFI)
 109     BlacklistFile = "cfi_blacklist.txt";
 110   else if (Kinds & (Undefined | Integer | Nullability))
 111     BlacklistFile = "ubsan_blacklist.txt";
 112
 113   if (BlacklistFile) {
 114     clang::SmallString<64> Path(D.ResourceDir);
 115     llvm::sys::path::append(Path, BlacklistFile);
 116     BLPath = Path.str();
 117     return true;
 118   }
 119   return false;
 120 }
 121
 122 /// Sets group bits for every group that has at least one representative already
 123 /// enabled in \p Kinds.
 124 static SanitizerMask setGroupBits(SanitizerMask Kinds) {
 125 #define SANITIZER(NAME, ID)
 126 #define SANITIZER_GROUP(NAME, ID, ALIAS)                                       \
 127   if (Kinds & SanitizerKind::ID)                                               \
 128     Kinds |= SanitizerKind::ID##Group;
 129 #include "clang/Basic/Sanitizers.def"
 130   return Kinds;
 131 }
 132
 133 static SanitizerMask parseSanitizeTrapArgs(const Driver &D,
 134                                            const llvm::opt::ArgList &Args) {
 135   SanitizerMask TrapRemove = 0; // During the loop below, the accumulated set of
 136                                 // sanitizers disabled by the current sanitizer
 137                                 // argument or any argument after it.
 138   SanitizerMask TrappingKinds = 0;
 139   SanitizerMask TrappingSupportedWithGroups = setGroupBits(TrappingSupported);
 140
 141   for (ArgList::const_reverse_iterator I = Args.rbegin(), E = Args.rend();
 142        I != E; ++I) {
 143     const auto *Arg = *I;
 144     if (Arg->getOption().matches(options::OPT_fsanitize_trap_EQ)) {
 145       Arg->claim();
 146       SanitizerMask Add = parseArgValues(D, Arg, true);
 147       Add &= ~TrapRemove;
 148       if (SanitizerMask InvalidValues = Add & ~TrappingSupportedWithGroups) {
 149         SanitizerSet S;
 150         S.Mask = InvalidValues;
 151         D.Diag(diag::err_drv_unsupported_option_argument) << "-fsanitize-trap"
 152                                                           << toString(S);
 153       }
 154       TrappingKinds |= expandSanitizerGroups(Add) & ~TrapRemove;
 155     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_trap_EQ)) {
 156       Arg->claim();
 157       TrapRemove |= expandSanitizerGroups(parseArgValues(D, Arg, true));
 158     } else if (Arg->getOption().matches(
 159                    options::OPT_fsanitize_undefined_trap_on_error)) {
 160       Arg->claim();
 161       TrappingKinds |=
 162           expandSanitizerGroups(UndefinedGroup & ~TrapRemove) & ~TrapRemove;
 163     } else if (Arg->getOption().matches(
 164                    options::OPT_fno_sanitize_undefined_trap_on_error)) {
 165       Arg->claim();
 166       TrapRemove |= expandSanitizerGroups(UndefinedGroup);
 167     }
 168   }
 169
 170   // Apply default trapping behavior.
 171   TrappingKinds |= TrappingDefault & ~TrapRemove;
 172
 173   return TrappingKinds;
 174 }
 175
 176 bool SanitizerArgs::needsUbsanRt() const {
 177   // All of these include ubsan.
 178   if (needsAsanRt() || needsMsanRt() || needsHwasanRt() || needsTsanRt() ||
 179       needsDfsanRt() || needsLsanRt() || needsCfiDiagRt() || needsScudoRt())
 180     return false;
 181
 182   return (Sanitizers.Mask & NeedsUbsanRt & ~TrapSanitizers.Mask) ||
 183          CoverageFeatures;
 184 }
 185
 186 bool SanitizerArgs::needsCfiRt() const {
 187   return !(Sanitizers.Mask & CFI & ~TrapSanitizers.Mask) && CfiCrossDso &&
 188          !ImplicitCfiRuntime;
 189 }
 190
 191 bool SanitizerArgs::needsCfiDiagRt() const {
 192   return (Sanitizers.Mask & CFI & ~TrapSanitizers.Mask) && CfiCrossDso &&
 193          !ImplicitCfiRuntime;
 194 }
 195
 196 bool SanitizerArgs::requiresPIE() const {
 197   return NeedPIE || (Sanitizers.Mask & RequiresPIE);
 198 }
 199
 200 bool SanitizerArgs::needsUnwindTables() const {
 201   return Sanitizers.Mask & NeedsUnwindTables;
 202 }
 203
 204 SanitizerArgs::SanitizerArgs(const ToolChain &TC,
 205                              const llvm::opt::ArgList &Args) {
 206   SanitizerMask AllRemove = 0;  // During the loop below, the accumulated set of
 207                                 // sanitizers disabled by the current sanitizer
 208                                 // argument or any argument after it.
 209   SanitizerMask AllAddedKinds = 0;  // Mask of all sanitizers ever enabled by
 210                                     // -fsanitize= flags (directly or via group
 211                                     // expansion), some of which may be disabled
 212                                     // later. Used to carefully prune
 213                                     // unused-argument diagnostics.
 214   SanitizerMask DiagnosedKinds = 0;  // All Kinds we have diagnosed up to now.
 215                                      // Used to deduplicate diagnostics.
 216   SanitizerMask Kinds = 0;
 217   const SanitizerMask Supported = setGroupBits(TC.getSupportedSanitizers());
 218   ToolChain::RTTIMode RTTIMode = TC.getRTTIMode();
 219
 220   const Driver &D = TC.getDriver();
 221   SanitizerMask TrappingKinds = parseSanitizeTrapArgs(D, Args);
 222   SanitizerMask InvalidTrappingKinds = TrappingKinds & NotAllowedWithTrap;
 223
 224   MinimalRuntime =
 225       Args.hasFlag(options::OPT_fsanitize_minimal_runtime,
 226                    options::OPT_fno_sanitize_minimal_runtime, MinimalRuntime);
 227
 228   // The object size sanitizer should not be enabled at -O0.
 229   Arg *OptLevel = Args.getLastArg(options::OPT_O_Group);
 230   bool RemoveObjectSizeAtO0 =
 231       !OptLevel || OptLevel->getOption().matches(options::OPT_O0);
 232
 233   for (ArgList::const_reverse_iterator I = Args.rbegin(), E = Args.rend();
 234        I != E; ++I) {
 235     const auto *Arg = *I;
 236     if (Arg->getOption().matches(options::OPT_fsanitize_EQ)) {
 237       Arg->claim();
 238       SanitizerMask Add = parseArgValues(D, Arg, /*AllowGroups=*/true);
 239
 240       if (RemoveObjectSizeAtO0) {
 241         AllRemove |= SanitizerKind::ObjectSize;
 242
 243         // The user explicitly enabled the object size sanitizer. Warn that
 244         // that this does nothing at -O0.
 245         if (Add & SanitizerKind::ObjectSize)
 246           D.Diag(diag::warn_drv_object_size_disabled_O0)
 247               << Arg->getAsString(Args);
 248       }
 249
 250       AllAddedKinds |= expandSanitizerGroups(Add);
 251
 252       // Avoid diagnosing any sanitizer which is disabled later.
 253       Add &= ~AllRemove;
 254       // At this point we have not expanded groups, so any unsupported
 255       // sanitizers in Add are those which have been explicitly enabled.
 256       // Diagnose them.
 257       if (SanitizerMask KindsToDiagnose =
 258               Add & InvalidTrappingKinds & ~DiagnosedKinds) {
 259         std::string Desc = describeSanitizeArg(*I, KindsToDiagnose);
 260         D.Diag(diag::err_drv_argument_not_allowed_with)
 261             << Desc << "-fsanitize-trap=undefined";
 262         DiagnosedKinds |= KindsToDiagnose;
 263       }
 264       Add &= ~InvalidTrappingKinds;
 265
 266       if (MinimalRuntime) {
 267         if (SanitizerMask KindsToDiagnose =
 268                 Add & NotAllowedWithMinimalRuntime & ~DiagnosedKinds) {
 269           std::string Desc = describeSanitizeArg(*I, KindsToDiagnose);
 270           D.Diag(diag::err_drv_argument_not_allowed_with)
 271               << Desc << "-fsanitize-minimal-runtime";
 272           DiagnosedKinds |= KindsToDiagnose;
 273         }
 274         Add &= ~NotAllowedWithMinimalRuntime;
 275       }
 276
 277       if (SanitizerMask KindsToDiagnose = Add & ~Supported & ~DiagnosedKinds) {
 278         std::string Desc = describeSanitizeArg(*I, KindsToDiagnose);
 279         D.Diag(diag::err_drv_unsupported_opt_for_target)
 280             << Desc << TC.getTriple().str();
 281         DiagnosedKinds |= KindsToDiagnose;
 282       }
 283       Add &= Supported;
 284
 285       // Test for -fno-rtti + explicit -fsanitizer=vptr before expanding groups
 286       // so we don't error out if -fno-rtti and -fsanitize=undefined were
 287       // passed.
 288       if (Add & Vptr &&
 289           (RTTIMode == ToolChain::RM_DisabledImplicitly ||
 290            RTTIMode == ToolChain::RM_DisabledExplicitly)) {
 291         if (RTTIMode == ToolChain::RM_DisabledImplicitly)
 292           // Warn about not having rtti enabled if the vptr sanitizer is
 293           // explicitly enabled
 294           D.Diag(diag::warn_drv_disabling_vptr_no_rtti_default);
 295         else {
 296           const llvm::opt::Arg *NoRTTIArg = TC.getRTTIArg();
 297           assert(NoRTTIArg &&
 298                  "RTTI disabled explicitly but we have no argument!");
 299           D.Diag(diag::err_drv_argument_not_allowed_with)
 300               << "-fsanitize=vptr" << NoRTTIArg->getAsString(Args);
 301         }
 302
 303         // Take out the Vptr sanitizer from the enabled sanitizers
 304         AllRemove |= Vptr;
 305       }
 306
 307       Add = expandSanitizerGroups(Add);
 308       // Group expansion may have enabled a sanitizer which is disabled later.
 309       Add &= ~AllRemove;
 310       // Silently discard any unsupported sanitizers implicitly enabled through
 311       // group expansion.
 312       Add &= ~InvalidTrappingKinds;
 313       if (MinimalRuntime) {
 314         Add &= ~NotAllowedWithMinimalRuntime;
 315       }
 316       Add &= Supported;
 317
 318       if (Add & Fuzzer)
 319         Add |= FuzzerNoLink;
 320
 321       // Enable coverage if the fuzzing flag is set.
 322       if (Add & FuzzerNoLink) {
 323         CoverageFeatures |= CoverageInline8bitCounters | CoverageIndirCall |
 324                             CoverageTraceCmp | CoveragePCTable;
 325         // Due to TLS differences, stack depth tracking is only enabled on Linux
 326         if (TC.getTriple().isOSLinux())
 327           CoverageFeatures |= CoverageStackDepth;
 328       }
 329
 330       Kinds |= Add;
 331     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_EQ)) {
 332       Arg->claim();
 333       SanitizerMask Remove = parseArgValues(D, Arg, true);
 334       AllRemove |= expandSanitizerGroups(Remove);
 335     }
 336   }
 337
 338   // Enable toolchain specific default sanitizers if not explicitly disabled.
 339   Kinds |= TC.getDefaultSanitizers() & ~AllRemove;
 340
 341   // We disable the vptr sanitizer if it was enabled by group expansion but RTTI
 342   // is disabled.
 343   if ((Kinds & Vptr) &&
 344       (RTTIMode == ToolChain::RM_DisabledImplicitly ||
 345        RTTIMode == ToolChain::RM_DisabledExplicitly)) {
 346     Kinds &= ~Vptr;
 347   }
 348
 349   // Check that LTO is enabled if we need it.
 350   if ((Kinds & NeedsLTO) && !D.isUsingLTO()) {
 351     D.Diag(diag::err_drv_argument_only_allowed_with)
 352         << lastArgumentForMask(D, Args, Kinds & NeedsLTO) << "-flto";
 353   }
 354
 355   // Report error if there are non-trapping sanitizers that require
 356   // c++abi-specific  parts of UBSan runtime, and they are not provided by the
 357   // toolchain. We don't have a good way to check the latter, so we just
 358   // check if the toolchan supports vptr.
 359   if (~Supported & Vptr) {
 360     SanitizerMask KindsToDiagnose = Kinds & ~TrappingKinds & NeedsUbsanCxxRt;
 361     // The runtime library supports the Microsoft C++ ABI, but only well enough
 362     // for CFI. FIXME: Remove this once we support vptr on Windows.
 363     if (TC.getTriple().isOSWindows())
 364       KindsToDiagnose &= ~CFI;
 365     if (KindsToDiagnose) {
 366       SanitizerSet S;
 367       S.Mask = KindsToDiagnose;
 368       D.Diag(diag::err_drv_unsupported_opt_for_target)
 369           << ("-fno-sanitize-trap=" + toString(S)) << TC.getTriple().str();
 370       Kinds &= ~KindsToDiagnose;
 371     }
 372   }
 373
 374   // Warn about incompatible groups of sanitizers.
 375   std::pair<SanitizerMask, SanitizerMask> IncompatibleGroups[] = {
 376       std::make_pair(Address, Thread | Memory),
 377       std::make_pair(Thread, Memory),
 378       std::make_pair(Leak, Thread | Memory),
 379       std::make_pair(KernelAddress, Address | Leak | Thread | Memory),
 380       std::make_pair(HWAddress, Address | Thread | Memory | KernelAddress),
 381       std::make_pair(Efficiency, Address | HWAddress | Leak | Thread | Memory |
 382                                      KernelAddress),
 383       std::make_pair(Scudo, Address | HWAddress | Leak | Thread | Memory |
 384                                 KernelAddress | Efficiency)};
 385   for (auto G : IncompatibleGroups) {
 386     SanitizerMask Group = G.first;
 387     if (Kinds & Group) {
 388       if (SanitizerMask Incompatible = Kinds & G.second) {
 389         D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 390             << lastArgumentForMask(D, Args, Group)
 391             << lastArgumentForMask(D, Args, Incompatible);
 392         Kinds &= ~Incompatible;
 393       }
 394     }
 395   }
 396   // FIXME: Currently -fsanitize=leak is silently ignored in the presence of
 397   // -fsanitize=address. Perhaps it should print an error, or perhaps
 398   // -f(-no)sanitize=leak should change whether leak detection is enabled by
 399   // default in ASan?
 400
 401   // Parse -f(no-)?sanitize-recover flags.
 402   SanitizerMask RecoverableKinds = RecoverableByDefault;
 403   SanitizerMask DiagnosedUnrecoverableKinds = 0;
 404   for (const auto *Arg : Args) {
 405     const char *DeprecatedReplacement = nullptr;
 406     if (Arg->getOption().matches(options::OPT_fsanitize_recover)) {
 407       DeprecatedReplacement =
 408           "-fsanitize-recover=undefined,integer' or '-fsanitize-recover=all";
 409       RecoverableKinds |= expandSanitizerGroups(LegacyFsanitizeRecoverMask);
 410       Arg->claim();
 411     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_recover)) {
 412       DeprecatedReplacement = "-fno-sanitize-recover=undefined,integer' or "
 413                               "'-fno-sanitize-recover=all";
 414       RecoverableKinds &= ~expandSanitizerGroups(LegacyFsanitizeRecoverMask);
 415       Arg->claim();
 416     } else if (Arg->getOption().matches(options::OPT_fsanitize_recover_EQ)) {
 417       SanitizerMask Add = parseArgValues(D, Arg, true);
 418       // Report error if user explicitly tries to recover from unrecoverable
 419       // sanitizer.
 420       if (SanitizerMask KindsToDiagnose =
 421               Add & Unrecoverable & ~DiagnosedUnrecoverableKinds) {
 422         SanitizerSet SetToDiagnose;
 423         SetToDiagnose.Mask |= KindsToDiagnose;
 424         D.Diag(diag::err_drv_unsupported_option_argument)
 425             << Arg->getOption().getName() << toString(SetToDiagnose);
 426         DiagnosedUnrecoverableKinds |= KindsToDiagnose;
 427       }
 428       RecoverableKinds |= expandSanitizerGroups(Add);
 429       Arg->claim();
 430     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_recover_EQ)) {
 431       RecoverableKinds &= ~expandSanitizerGroups(parseArgValues(D, Arg, true));
 432       Arg->claim();
 433     }
 434     if (DeprecatedReplacement) {
 435       D.Diag(diag::warn_drv_deprecated_arg) << Arg->getAsString(Args)
 436                                             << DeprecatedReplacement;
 437     }
 438   }
 439   RecoverableKinds &= Kinds;
 440   RecoverableKinds &= ~Unrecoverable;
 441
 442   TrappingKinds &= Kinds;
 443   RecoverableKinds &= ~TrappingKinds;
 444
 445   // Setup blacklist files.
 446   // Add default blacklist from resource directory.
 447   {
 448     std::string BLPath;
 449     if (getDefaultBlacklist(D, Kinds, BLPath) && llvm::sys::fs::exists(BLPath))
 450       BlacklistFiles.push_back(BLPath);
 451   }
 452   // Parse -f(no-)sanitize-blacklist options.
 453   for (const auto *Arg : Args) {
 454     if (Arg->getOption().matches(options::OPT_fsanitize_blacklist)) {
 455       Arg->claim();
 456       std::string BLPath = Arg->getValue();
 457       if (llvm::sys::fs::exists(BLPath)) {
 458         BlacklistFiles.push_back(BLPath);
 459         ExtraDeps.push_back(BLPath);
 460       } else
 461         D.Diag(clang::diag::err_drv_no_such_file) << BLPath;
 462
 463     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_blacklist)) {
 464       Arg->claim();
 465       BlacklistFiles.clear();
 466       ExtraDeps.clear();
 467     }
 468   }
 469   // Validate blacklists format.
 470   {
 471     std::string BLError;
 472     std::unique_ptr<llvm::SpecialCaseList> SCL(
 473         llvm::SpecialCaseList::create(BlacklistFiles, BLError));
 474     if (!SCL.get())
 475       D.Diag(clang::diag::err_drv_malformed_sanitizer_blacklist) << BLError;
 476   }
 477
 478   // Parse -f[no-]sanitize-memory-track-origins[=level] options.
 479   if (AllAddedKinds & Memory) {
 480     if (Arg *A =
 481             Args.getLastArg(options::OPT_fsanitize_memory_track_origins_EQ,
 482                             options::OPT_fsanitize_memory_track_origins,
 483                             options::OPT_fno_sanitize_memory_track_origins)) {
 484       if (A->getOption().matches(options::OPT_fsanitize_memory_track_origins)) {
 485         MsanTrackOrigins = 2;
 486       } else if (A->getOption().matches(
 487                      options::OPT_fno_sanitize_memory_track_origins)) {
 488         MsanTrackOrigins = 0;
 489       } else {
 490         StringRef S = A->getValue();
 491         if (S.getAsInteger(0, MsanTrackOrigins) || MsanTrackOrigins < 0 ||
 492             MsanTrackOrigins > 2) {
 493           D.Diag(clang::diag::err_drv_invalid_value) << A->getAsString(Args) << S;
 494         }
 495       }
 496     }
 497     MsanUseAfterDtor =
 498         Args.hasFlag(options::OPT_fsanitize_memory_use_after_dtor,
 499                      options::OPT_fno_sanitize_memory_use_after_dtor,
 500                      MsanUseAfterDtor);
 501     NeedPIE |= !(TC.getTriple().isOSLinux() &&
 502                  TC.getTriple().getArch() == llvm::Triple::x86_64);
 503   } else {
 504     MsanUseAfterDtor = false;
 505   }
 506
 507   if (AllAddedKinds & Thread) {
 508     TsanMemoryAccess = Args.hasFlag(options::OPT_fsanitize_thread_memory_access,
 509                                     options::OPT_fno_sanitize_thread_memory_access,
 510                                     TsanMemoryAccess);
 511     TsanFuncEntryExit = Args.hasFlag(options::OPT_fsanitize_thread_func_entry_exit,
 512                                      options::OPT_fno_sanitize_thread_func_entry_exit,
 513                                      TsanFuncEntryExit);
 514     TsanAtomics = Args.hasFlag(options::OPT_fsanitize_thread_atomics,
 515                                options::OPT_fno_sanitize_thread_atomics,
 516                                TsanAtomics);
 517   }
 518
 519   if (AllAddedKinds & CFI) {
 520     CfiCrossDso = Args.hasFlag(options::OPT_fsanitize_cfi_cross_dso,
 521                                options::OPT_fno_sanitize_cfi_cross_dso, false);
 522     // Without PIE, external function address may resolve to a PLT record, which
 523     // can not be verified by the target module.
 524     NeedPIE |= CfiCrossDso;
 525     CfiICallGeneralizePointers =
 526         Args.hasArg(options::OPT_fsanitize_cfi_icall_generalize_pointers);
 527
 528     if (CfiCrossDso && CfiICallGeneralizePointers)
 529       D.Diag(diag::err_drv_argument_not_allowed_with)
 530           << "-fsanitize-cfi-cross-dso"
 531           << "-fsanitize-cfi-icall-generalize-pointers";
 532   }
 533
 534   Stats = Args.hasFlag(options::OPT_fsanitize_stats,
 535                        options::OPT_fno_sanitize_stats, false);
 536
 537   if (MinimalRuntime) {
 538     SanitizerMask IncompatibleMask =
 539         Kinds & ~setGroupBits(CompatibleWithMinimalRuntime);
 540     if (IncompatibleMask)
 541       D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 542           << "-fsanitize-minimal-runtime"
 543           << lastArgumentForMask(D, Args, IncompatibleMask);
 544
 545     SanitizerMask NonTrappingCfi = Kinds & CFI & ~TrappingKinds;
 546     if (NonTrappingCfi)
 547       D.Diag(clang::diag::err_drv_argument_only_allowed_with)
 548           << "fsanitize-minimal-runtime"
 549           << "fsanitize-trap=cfi";
 550   }
 551
 552   // Parse -f(no-)?sanitize-coverage flags if coverage is supported by the
 553   // enabled sanitizers.
 554   for (const auto *Arg : Args) {
 555     if (Arg->getOption().matches(options::OPT_fsanitize_coverage)) {
 556       int LegacySanitizeCoverage;
 557       if (Arg->getNumValues() == 1 &&
 558           !StringRef(Arg->getValue(0))
 559                .getAsInteger(0, LegacySanitizeCoverage)) {
 560         CoverageFeatures = 0;
 561         Arg->claim();
 562         if (LegacySanitizeCoverage != 0) {
 563           D.Diag(diag::warn_drv_deprecated_arg)
 564               << Arg->getAsString(Args) << "-fsanitize-coverage=trace-pc-guard";
 565         }
 566         continue;
 567       }
 568       CoverageFeatures |= parseCoverageFeatures(D, Arg);
 569
 570       // Disable coverage and not claim the flags if there is at least one
 571       // non-supporting sanitizer.
 572       if (!(AllAddedKinds & ~AllRemove & ~setGroupBits(SupportsCoverage))) {
 573         Arg->claim();
 574       } else {
 575         CoverageFeatures = 0;
 576       }
 577     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_coverage)) {
 578       Arg->claim();
 579       CoverageFeatures &= ~parseCoverageFeatures(D, Arg);
 580     }
 581   }
 582   // Choose at most one coverage type: function, bb, or edge.
 583   if ((CoverageFeatures & CoverageFunc) && (CoverageFeatures & CoverageBB))
 584     D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 585         << "-fsanitize-coverage=func"
 586         << "-fsanitize-coverage=bb";
 587   if ((CoverageFeatures & CoverageFunc) && (CoverageFeatures & CoverageEdge))
 588     D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 589         << "-fsanitize-coverage=func"
 590         << "-fsanitize-coverage=edge";
 591   if ((CoverageFeatures & CoverageBB) && (CoverageFeatures & CoverageEdge))
 592     D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 593         << "-fsanitize-coverage=bb"
 594         << "-fsanitize-coverage=edge";
 595   // Basic block tracing and 8-bit counters require some type of coverage
 596   // enabled.
 597   if (CoverageFeatures & CoverageTraceBB)
 598     D.Diag(clang::diag::warn_drv_deprecated_arg)
 599         << "-fsanitize-coverage=trace-bb"
 600         << "-fsanitize-coverage=trace-pc-guard";
 601   if (CoverageFeatures & Coverage8bitCounters)
 602     D.Diag(clang::diag::warn_drv_deprecated_arg)
 603         << "-fsanitize-coverage=8bit-counters"
 604         << "-fsanitize-coverage=trace-pc-guard";
 605
 606   int InsertionPointTypes = CoverageFunc | CoverageBB | CoverageEdge;
 607   int InstrumentationTypes =
 608       CoverageTracePC | CoverageTracePCGuard | CoverageInline8bitCounters;
 609   if ((CoverageFeatures & InsertionPointTypes) &&
 610       !(CoverageFeatures & InstrumentationTypes)) {
 611     D.Diag(clang::diag::warn_drv_deprecated_arg)
 612         << "-fsanitize-coverage=[func|bb|edge]"
 613         << "-fsanitize-coverage=[func|bb|edge],[trace-pc-guard|trace-pc]";
 614   }
 615
 616   // trace-pc w/o func/bb/edge implies edge.
 617   if (!(CoverageFeatures & InsertionPointTypes)) {
 618     if (CoverageFeatures &
 619         (CoverageTracePC | CoverageTracePCGuard | CoverageInline8bitCounters))
 620       CoverageFeatures |= CoverageEdge;
 621
 622     if (CoverageFeatures & CoverageStackDepth)
 623       CoverageFeatures |= CoverageFunc;
 624   }
 625
 626   SharedRuntime =
 627       Args.hasFlag(options::OPT_shared_libsan, options::OPT_static_libsan,
 628                    TC.getTriple().isAndroid() || TC.getTriple().isOSFuchsia() ||
 629                        TC.getTriple().isOSDarwin());
 630
 631   ImplicitCfiRuntime = TC.getTriple().isAndroid();
 632
 633   if (AllAddedKinds & Address) {
 634     NeedPIE |= TC.getTriple().isOSFuchsia();
 635     if (Arg *A =
 636             Args.getLastArg(options::OPT_fsanitize_address_field_padding)) {
 637         StringRef S = A->getValue();
 638         // Legal values are 0 and 1, 2, but in future we may add more levels.
 639         if (S.getAsInteger(0, AsanFieldPadding) || AsanFieldPadding < 0 ||
 640             AsanFieldPadding > 2) {
 641           D.Diag(clang::diag::err_drv_invalid_value) << A->getAsString(Args) << S;
 642         }
 643     }
 644
 645     if (Arg *WindowsDebugRTArg =
 646             Args.getLastArg(options::OPT__SLASH_MTd, options::OPT__SLASH_MT,
 647                             options::OPT__SLASH_MDd, options::OPT__SLASH_MD,
 648                             options::OPT__SLASH_LDd, options::OPT__SLASH_LD)) {
 649       switch (WindowsDebugRTArg->getOption().getID()) {
 650       case options::OPT__SLASH_MTd:
 651       case options::OPT__SLASH_MDd:
 652       case options::OPT__SLASH_LDd:
 653         D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 654             << WindowsDebugRTArg->getAsString(Args)
 655             << lastArgumentForMask(D, Args, Address);
 656         D.Diag(clang::diag::note_drv_address_sanitizer_debug_runtime);
 657       }
 658     }
 659
 660     AsanUseAfterScope = Args.hasFlag(
 661         options::OPT_fsanitize_address_use_after_scope,
 662         options::OPT_fno_sanitize_address_use_after_scope, AsanUseAfterScope);
 663
 664     // As a workaround for a bug in gold 2.26 and earlier, dead stripping of
 665     // globals in ASan is disabled by default on ELF targets.
 666     // See https://sourceware.org/bugzilla/show_bug.cgi?id=19002
 667     AsanGlobalsDeadStripping =
 668         !TC.getTriple().isOSBinFormatELF() || TC.getTriple().isOSFuchsia() ||
 669         Args.hasArg(options::OPT_fsanitize_address_globals_dead_stripping);
 670   } else {
 671     AsanUseAfterScope = false;
 672   }
 673
 674   if (AllAddedKinds & SafeStack) {
 675     // SafeStack runtime is built into the system on Fuchsia.
 676     SafeStackRuntime = !TC.getTriple().isOSFuchsia();
 677   }
 678
 679   // Parse -link-cxx-sanitizer flag.
 680   LinkCXXRuntimes =
 681       Args.hasArg(options::OPT_fsanitize_link_cxx_runtime) || D.CCCIsCXX();
 682
 683   // Finally, initialize the set of available and recoverable sanitizers.
 684   Sanitizers.Mask |= Kinds;
 685   RecoverableSanitizers.Mask |= RecoverableKinds;
 686   TrapSanitizers.Mask |= TrappingKinds;
 687   assert(!(RecoverableKinds & TrappingKinds) &&
 688          "Overlap between recoverable and trapping sanitizers");
 689 }
 690
 691 static std::string toString(const clang::SanitizerSet &Sanitizers) {
 692   std::string Res;
 693 #define SANITIZER(NAME, ID)                                                    \
 694   if (Sanitizers.has(ID)) {                                                    \
 695     if (!Res.empty())                                                          \
 696       Res += ",";                                                              \
 697     Res += NAME;                                                               \
 698   }
 699 #include "clang/Basic/Sanitizers.def"
 700   return Res;
 701 }
 702
 703 static void addIncludeLinkerOption(const ToolChain &TC,
 704                                    const llvm::opt::ArgList &Args,
 705                                    llvm::opt::ArgStringList &CmdArgs,
 706                                    StringRef SymbolName) {
 707   SmallString<64> LinkerOptionFlag;
 708   LinkerOptionFlag = "--linker-option=/include:";
 709   if (TC.getTriple().getArch() == llvm::Triple::x86) {
 710     // Win32 mangles C function names with a '_' prefix.
 711     LinkerOptionFlag += '_';
 712   }
 713   LinkerOptionFlag += SymbolName;
 714   CmdArgs.push_back(Args.MakeArgString(LinkerOptionFlag));
 715 }
 716
 717 void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
 718                             llvm::opt::ArgStringList &CmdArgs,
 719                             types::ID InputType) const {
 720   // NVPTX doesn't currently support sanitizers.  Bailing out here means that
 721   // e.g. -fsanitize=address applies only to host code, which is what we want
 722   // for now.
 723   if (TC.getTriple().isNVPTX())
 724     return;
 725
 726   // Translate available CoverageFeatures to corresponding clang-cc1 flags.
 727   // Do it even if Sanitizers.empty() since some forms of coverage don't require
 728   // sanitizers.
 729   std::pair<int, const char *> CoverageFlags[] = {
 730     std::make_pair(CoverageFunc, "-fsanitize-coverage-type=1"),
 731     std::make_pair(CoverageBB, "-fsanitize-coverage-type=2"),
 732     std::make_pair(CoverageEdge, "-fsanitize-coverage-type=3"),
 733     std::make_pair(CoverageIndirCall, "-fsanitize-coverage-indirect-calls"),
 734     std::make_pair(CoverageTraceBB, "-fsanitize-coverage-trace-bb"),
 735     std::make_pair(CoverageTraceCmp, "-fsanitize-coverage-trace-cmp"),
 736     std::make_pair(CoverageTraceDiv, "-fsanitize-coverage-trace-div"),
 737     std::make_pair(CoverageTraceGep, "-fsanitize-coverage-trace-gep"),
 738     std::make_pair(Coverage8bitCounters, "-fsanitize-coverage-8bit-counters"),
 739     std::make_pair(CoverageTracePC, "-fsanitize-coverage-trace-pc"),
 740     std::make_pair(CoverageTracePCGuard, "-fsanitize-coverage-trace-pc-guard"),
 741     std::make_pair(CoverageInline8bitCounters, "-fsanitize-coverage-inline-8bit-counters"),
 742     std::make_pair(CoveragePCTable, "-fsanitize-coverage-pc-table"),
 743     std::make_pair(CoverageNoPrune, "-fsanitize-coverage-no-prune"),
 744     std::make_pair(CoverageStackDepth, "-fsanitize-coverage-stack-depth")};
 745   for (auto F : CoverageFlags) {
 746     if (CoverageFeatures & F.first)
 747       CmdArgs.push_back(F.second);
 748   }
 749
 750   if (TC.getTriple().isOSWindows() && needsUbsanRt()) {
 751     // Instruct the code generator to embed linker directives in the object file
 752     // that cause the required runtime libraries to be linked.
 753     CmdArgs.push_back(Args.MakeArgString(
 754         "--dependent-lib=" + TC.getCompilerRT(Args, "ubsan_standalone")));
 755     if (types::isCXX(InputType))
 756       CmdArgs.push_back(Args.MakeArgString(
 757           "--dependent-lib=" + TC.getCompilerRT(Args, "ubsan_standalone_cxx")));
 758   }
 759   if (TC.getTriple().isOSWindows() && needsStatsRt()) {
 760     CmdArgs.push_back(Args.MakeArgString("--dependent-lib=" +
 761                                          TC.getCompilerRT(Args, "stats_client")));
 762
 763     // The main executable must export the stats runtime.
 764     // FIXME: Only exporting from the main executable (e.g. based on whether the
 765     // translation unit defines main()) would save a little space, but having
 766     // multiple copies of the runtime shouldn't hurt.
 767     CmdArgs.push_back(Args.MakeArgString("--dependent-lib=" +
 768                                          TC.getCompilerRT(Args, "stats")));
 769     addIncludeLinkerOption(TC, Args, CmdArgs, "__sanitizer_stats_register");
 770   }
 771
 772   if (Sanitizers.empty())
 773     return;
 774   CmdArgs.push_back(Args.MakeArgString("-fsanitize=" + toString(Sanitizers)));
 775
 776   if (!RecoverableSanitizers.empty())
 777     CmdArgs.push_back(Args.MakeArgString("-fsanitize-recover=" +
 778                                          toString(RecoverableSanitizers)));
 779
 780   if (!TrapSanitizers.empty())
 781     CmdArgs.push_back(
 782         Args.MakeArgString("-fsanitize-trap=" + toString(TrapSanitizers)));
 783
 784   for (const auto &BLPath : BlacklistFiles) {
 785     SmallString<64> BlacklistOpt("-fsanitize-blacklist=");
 786     BlacklistOpt += BLPath;
 787     CmdArgs.push_back(Args.MakeArgString(BlacklistOpt));
 788   }
 789   for (const auto &Dep : ExtraDeps) {
 790     SmallString<64> ExtraDepOpt("-fdepfile-entry=");
 791     ExtraDepOpt += Dep;
 792     CmdArgs.push_back(Args.MakeArgString(ExtraDepOpt));
 793   }
 794
 795   if (MsanTrackOrigins)
 796     CmdArgs.push_back(Args.MakeArgString("-fsanitize-memory-track-origins=" +
 797                                          Twine(MsanTrackOrigins)));
 798
 799   if (MsanUseAfterDtor)
 800     CmdArgs.push_back("-fsanitize-memory-use-after-dtor");
 801
 802   // FIXME: Pass these parameters as function attributes, not as -llvm flags.
 803   if (!TsanMemoryAccess) {
 804     CmdArgs.push_back("-mllvm");
 805     CmdArgs.push_back("-tsan-instrument-memory-accesses=0");
 806     CmdArgs.push_back("-mllvm");
 807     CmdArgs.push_back("-tsan-instrument-memintrinsics=0");
 808   }
 809   if (!TsanFuncEntryExit) {
 810     CmdArgs.push_back("-mllvm");
 811     CmdArgs.push_back("-tsan-instrument-func-entry-exit=0");
 812   }
 813   if (!TsanAtomics) {
 814     CmdArgs.push_back("-mllvm");
 815     CmdArgs.push_back("-tsan-instrument-atomics=0");
 816   }
 817
 818   if (CfiCrossDso)
 819     CmdArgs.push_back("-fsanitize-cfi-cross-dso");
 820
 821   if (CfiICallGeneralizePointers)
 822     CmdArgs.push_back("-fsanitize-cfi-icall-generalize-pointers");
 823
 824   if (Stats)
 825     CmdArgs.push_back("-fsanitize-stats");
 826
 827   if (MinimalRuntime)
 828     CmdArgs.push_back("-fsanitize-minimal-runtime");
 829
 830   if (AsanFieldPadding)
 831     CmdArgs.push_back(Args.MakeArgString("-fsanitize-address-field-padding=" +
 832                                          Twine(AsanFieldPadding)));
 833
 834   if (AsanUseAfterScope)
 835     CmdArgs.push_back("-fsanitize-address-use-after-scope");
 836
 837   if (AsanGlobalsDeadStripping)
 838     CmdArgs.push_back("-fsanitize-address-globals-dead-stripping");
 839
 840   // MSan: Workaround for PR16386.
 841   // ASan: This is mainly to help LSan with cases such as
 842   // https://github.com/google/sanitizers/issues/373
 843   // We can't make this conditional on -fsanitize=leak, as that flag shouldn't
 844   // affect compilation.
 845   if (Sanitizers.has(Memory) || Sanitizers.has(Address))
 846     CmdArgs.push_back("-fno-assume-sane-operator-new");
 847
 848   // Require -fvisibility= flag on non-Windows when compiling if vptr CFI is
 849   // enabled.
 850   if (Sanitizers.hasOneOf(CFIClasses) && !TC.getTriple().isOSWindows() &&
 851       !Args.hasArg(options::OPT_fvisibility_EQ)) {
 852     TC.getDriver().Diag(clang::diag::err_drv_argument_only_allowed_with)
 853         << lastArgumentForMask(TC.getDriver(), Args,
 854                                Sanitizers.Mask & CFIClasses)
 855         << "-fvisibility=";
 856   }
 857 }
 858
 859 SanitizerMask parseArgValues(const Driver &D, const llvm::opt::Arg *A,
 860                              bool DiagnoseErrors) {
 861   assert((A->getOption().matches(options::OPT_fsanitize_EQ) ||
 862           A->getOption().matches(options::OPT_fno_sanitize_EQ) ||
 863           A->getOption().matches(options::OPT_fsanitize_recover_EQ) ||
 864           A->getOption().matches(options::OPT_fno_sanitize_recover_EQ) ||
 865           A->getOption().matches(options::OPT_fsanitize_trap_EQ) ||
 866           A->getOption().matches(options::OPT_fno_sanitize_trap_EQ)) &&
 867          "Invalid argument in parseArgValues!");
 868   SanitizerMask Kinds = 0;
 869   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
 870     const char *Value = A->getValue(i);
 871     SanitizerMask Kind;
 872     // Special case: don't accept -fsanitize=all.
 873     if (A->getOption().matches(options::OPT_fsanitize_EQ) &&
 874         0 == strcmp("all", Value))
 875       Kind = 0;
 876     // Similarly, don't accept -fsanitize=efficiency-all.
 877     else if (A->getOption().matches(options::OPT_fsanitize_EQ) &&
 878         0 == strcmp("efficiency-all", Value))
 879       Kind = 0;
 880     else
 881       Kind = parseSanitizerValue(Value, /*AllowGroups=*/true);
 882
 883     if (Kind)
 884       Kinds |= Kind;
 885     else if (DiagnoseErrors)
 886       D.Diag(clang::diag::err_drv_unsupported_option_argument)
 887           << A->getOption().getName() << Value;
 888   }
 889   return Kinds;
 890 }
 891
 892 int parseCoverageFeatures(const Driver &D, const llvm::opt::Arg *A) {
 893   assert(A->getOption().matches(options::OPT_fsanitize_coverage) ||
 894          A->getOption().matches(options::OPT_fno_sanitize_coverage));
 895   int Features = 0;
 896   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
 897     const char *Value = A->getValue(i);
 898     int F = llvm::StringSwitch<int>(Value)
 899         .Case("func", CoverageFunc)
 900         .Case("bb", CoverageBB)
 901         .Case("edge", CoverageEdge)
 902         .Case("indirect-calls", CoverageIndirCall)
 903         .Case("trace-bb", CoverageTraceBB)
 904         .Case("trace-cmp", CoverageTraceCmp)
 905         .Case("trace-div", CoverageTraceDiv)
 906         .Case("trace-gep", CoverageTraceGep)
 907         .Case("8bit-counters", Coverage8bitCounters)
 908         .Case("trace-pc", CoverageTracePC)
 909         .Case("trace-pc-guard", CoverageTracePCGuard)
 910         .Case("no-prune", CoverageNoPrune)
 911         .Case("inline-8bit-counters", CoverageInline8bitCounters)
 912         .Case("pc-table", CoveragePCTable)
 913         .Case("stack-depth", CoverageStackDepth)
 914         .Default(0);
 915     if (F == 0)
 916       D.Diag(clang::diag::err_drv_unsupported_option_argument)
 917           << A->getOption().getName() << Value;
 918     Features |= F;
 919   }
 920   return Features;
 921 }
 922
 923 std::string lastArgumentForMask(const Driver &D, const llvm::opt::ArgList &Args,
 924                                 SanitizerMask Mask) {
 925   for (llvm::opt::ArgList::const_reverse_iterator I = Args.rbegin(),
 926                                                   E = Args.rend();
 927        I != E; ++I) {
 928     const auto *Arg = *I;
 929     if (Arg->getOption().matches(options::OPT_fsanitize_EQ)) {
 930       SanitizerMask AddKinds =
 931           expandSanitizerGroups(parseArgValues(D, Arg, false));
 932       if (AddKinds & Mask)
 933         return describeSanitizeArg(Arg, Mask);
 934     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_EQ)) {
 935       SanitizerMask RemoveKinds =
 936           expandSanitizerGroups(parseArgValues(D, Arg, false));
 937       Mask &= ~RemoveKinds;
 938     }
 939   }
 940   llvm_unreachable("arg list didn't provide expected value");
 941 }
 942
 943 std::string describeSanitizeArg(const llvm::opt::Arg *A, SanitizerMask Mask) {
 944   assert(A->getOption().matches(options::OPT_fsanitize_EQ)
 945          && "Invalid argument in describeSanitizerArg!");
 946
 947   std::string Sanitizers;
 948   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
 949     if (expandSanitizerGroups(
 950             parseSanitizerValue(A->getValue(i), /*AllowGroups=*/true)) &
 951         Mask) {
 952       if (!Sanitizers.empty())
 953         Sanitizers += ",";
 954       Sanitizers += A->getValue(i);
 955     }
 956   }
 957
 958   assert(!Sanitizers.empty() && "arg didn't provide expected value");
 959   return "-fsanitize=" + Sanitizers;
 960 }