| 1 | |
| 2 | |
| 3 | |
| 4 | |
| 5 | |
| 6 | |
| 7 | |
| 8 | |
| 9 | |
| 10 | |
| 11 | |
| 12 | |
| 13 | #include "clang/StaticAnalyzer/Core/PathSensitive/Store.h" |
| 14 | #include "clang/AST/ASTContext.h" |
| 15 | #include "clang/AST/CXXInheritance.h" |
| 16 | #include "clang/AST/CharUnits.h" |
| 17 | #include "clang/AST/Decl.h" |
| 18 | #include "clang/AST/DeclCXX.h" |
| 19 | #include "clang/AST/DeclObjC.h" |
| 20 | #include "clang/AST/Expr.h" |
| 21 | #include "clang/AST/Type.h" |
| 22 | #include "clang/Basic/LLVM.h" |
| 23 | #include "clang/StaticAnalyzer/Core/PathSensitive/BasicValueFactory.h" |
| 24 | #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h" |
| 25 | #include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h" |
| 26 | #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h" |
| 27 | #include "clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h" |
| 28 | #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h" |
| 29 | #include "clang/StaticAnalyzer/Core/PathSensitive/StoreRef.h" |
| 30 | #include "clang/StaticAnalyzer/Core/PathSensitive/SymExpr.h" |
| 31 | #include "llvm/ADT/APSInt.h" |
| 32 | #include "llvm/ADT/Optional.h" |
| 33 | #include "llvm/ADT/SmallVector.h" |
| 34 | #include "llvm/Support/Casting.h" |
| 35 | #include "llvm/Support/ErrorHandling.h" |
| 36 | #include <cassert> |
| 37 | #include <cstdint> |
| 38 | |
| 39 | using namespace clang; |
| 40 | using namespace ento; |
| 41 | |
| 42 | StoreManager::StoreManager(ProgramStateManager &stateMgr) |
| 43 | : svalBuilder(stateMgr.getSValBuilder()), StateMgr(stateMgr), |
| 44 | MRMgr(svalBuilder.getRegionManager()), Ctx(stateMgr.getContext()) {} |
| 45 | |
| 46 | StoreRef StoreManager::enterStackFrame(Store OldStore, |
| 47 | const CallEvent &Call, |
| 48 | const StackFrameContext *LCtx) { |
| 49 | StoreRef Store = StoreRef(OldStore, *this); |
| 50 | |
| 51 | SmallVector<CallEvent::FrameBindingTy, 16> InitialBindings; |
| 52 | Call.getInitialStackFrameContents(LCtx, InitialBindings); |
| 53 | |
| 54 | for (const auto &I : InitialBindings) |
| 55 | Store = Bind(Store.getStore(), I.first, I.second); |
| 56 | |
| 57 | return Store; |
| 58 | } |
| 59 | |
| 60 | const ElementRegion *StoreManager::MakeElementRegion(const SubRegion *Base, |
| 61 | QualType EleTy, |
| 62 | uint64_t index) { |
| 63 | NonLoc idx = svalBuilder.makeArrayIndex(index); |
| 64 | return MRMgr.getElementRegion(EleTy, idx, Base, svalBuilder.getContext()); |
| 65 | } |
| 66 | |
| 67 | const ElementRegion *StoreManager::GetElementZeroRegion(const SubRegion *R, |
| 68 | QualType T) { |
| 69 | NonLoc idx = svalBuilder.makeZeroArrayIndex(); |
| 70 | assert(!T.isNull()); |
| 71 | return MRMgr.getElementRegion(T, idx, R, Ctx); |
| 72 | } |
| 73 | |
| 74 | const MemRegion *StoreManager::castRegion(const MemRegion *R, QualType CastToTy) { |
| 75 | ASTContext &Ctx = StateMgr.getContext(); |
| 76 | |
| 77 | |
| 78 | if (CastToTy->isObjCObjectPointerType()) |
| 79 | return R->StripCasts(); |
| 80 | |
| 81 | if (CastToTy->isBlockPointerType()) { |
| 82 | |
| 83 | |
| 84 | |
| 85 | |
| 86 | if (isa<CodeTextRegion>(R) || isa<SymbolicRegion>(R)) |
| 87 | return R; |
| 88 | |
| 89 | |
| 90 | |
| 91 | return nullptr; |
| 92 | } |
| 93 | |
| 94 | |
| 95 | |
| 96 | QualType PointeeTy = CastToTy->getPointeeType(); |
| 97 | QualType CanonPointeeTy = Ctx.getCanonicalType(PointeeTy); |
| 98 | |
| 99 | |
| 100 | if (CanonPointeeTy.getLocalUnqualifiedType() == Ctx.VoidTy) |
| 101 | return R; |
| 102 | |
| 103 | |
| 104 | if (R->isBoundable()) |
| 105 | if (const auto *TR = dyn_cast<TypedValueRegion>(R)) { |
| 106 | QualType ObjTy = Ctx.getCanonicalType(TR->getValueType()); |
| 107 | if (CanonPointeeTy == ObjTy) |
| 108 | return R; |
| 109 | } |
| 110 | |
| 111 | |
| 112 | switch (R->getKind()) { |
| 113 | case MemRegion::CXXThisRegionKind: |
| 114 | case MemRegion::CodeSpaceRegionKind: |
| 115 | case MemRegion::StackLocalsSpaceRegionKind: |
| 116 | case MemRegion::StackArgumentsSpaceRegionKind: |
| 117 | case MemRegion::HeapSpaceRegionKind: |
| 118 | case MemRegion::UnknownSpaceRegionKind: |
| 119 | case MemRegion::StaticGlobalSpaceRegionKind: |
| 120 | case MemRegion::GlobalInternalSpaceRegionKind: |
| 121 | case MemRegion::GlobalSystemSpaceRegionKind: |
| 122 | case MemRegion::GlobalImmutableSpaceRegionKind: { |
| 123 | llvm_unreachable("Invalid region cast"); |
| 124 | } |
| 125 | |
| 126 | case MemRegion::FunctionCodeRegionKind: |
| 127 | case MemRegion::BlockCodeRegionKind: |
| 128 | case MemRegion::BlockDataRegionKind: |
| 129 | case MemRegion::StringRegionKind: |
| 130 | |
| 131 | case MemRegion::SymbolicRegionKind: |
| 132 | case MemRegion::AllocaRegionKind: |
| 133 | case MemRegion::CompoundLiteralRegionKind: |
| 134 | case MemRegion::FieldRegionKind: |
| 135 | case MemRegion::ObjCIvarRegionKind: |
| 136 | case MemRegion::ObjCStringRegionKind: |
| 137 | case MemRegion::VarRegionKind: |
| 138 | case MemRegion::CXXTempObjectRegionKind: |
| 139 | case MemRegion::CXXBaseObjectRegionKind: |
| 140 | case MemRegion::CXXDerivedObjectRegionKind: |
| 141 | return MakeElementRegion(cast<SubRegion>(R), PointeeTy); |
| 142 | |
| 143 | case MemRegion::ElementRegionKind: { |
| 144 | |
| 145 | |
| 146 | |
| 147 | |
| 148 | |
| 149 | |
| 150 | |
| 151 | |
| 152 | |
| 153 | |
| 154 | |
| 155 | |
| 156 | |
| 157 | |
| 158 | |
| 159 | |
| 160 | |
| 161 | |
| 162 | |
| 163 | const ElementRegion *elementR = cast<ElementRegion>(R); |
| 164 | const RegionRawOffset &rawOff = elementR->getAsArrayOffset(); |
| 165 | const MemRegion *baseR = rawOff.getRegion(); |
| 166 | |
| 167 | |
| 168 | |
| 169 | if (!baseR) |
| 170 | return nullptr; |
| 171 | |
| 172 | CharUnits off = rawOff.getOffset(); |
| 173 | |
| 174 | if (off.isZero()) { |
| 175 | |
| 176 | |
| 177 | |
| 178 | if (const auto *TR = dyn_cast<TypedValueRegion>(baseR)) { |
| 179 | QualType ObjTy = Ctx.getCanonicalType(TR->getValueType()); |
| 180 | QualType CanonPointeeTy = Ctx.getCanonicalType(PointeeTy); |
| 181 | if (CanonPointeeTy == ObjTy) |
| 182 | return baseR; |
| 183 | } |
| 184 | |
| 185 | |
| 186 | return MakeElementRegion(cast<SubRegion>(baseR), PointeeTy); |
| 187 | } |
| 188 | |
| 189 | |
| 190 | |
| 191 | |
| 192 | |
| 193 | |
| 194 | |
| 195 | |
| 196 | int64_t newIndex = 0; |
| 197 | const MemRegion *newSuperR = nullptr; |
| 198 | |
| 199 | |
| 200 | if (!PointeeTy->isIncompleteType()) { |
| 201 | |
| 202 | CharUnits pointeeTySize = Ctx.getTypeSizeInChars(PointeeTy); |
| 203 | if (!pointeeTySize.isZero()) { |
| 204 | |
| 205 | |
| 206 | |
| 207 | if (off % pointeeTySize == 0) { |
| 208 | newIndex = off / pointeeTySize; |
| 209 | newSuperR = baseR; |
| 210 | } |
| 211 | } |
| 212 | } |
| 213 | |
| 214 | if (!newSuperR) { |
| 215 | |
| 216 | |
| 217 | newSuperR = MakeElementRegion(cast<SubRegion>(baseR), Ctx.CharTy, |
| 218 | off.getQuantity()); |
| 219 | } |
| 220 | |
| 221 | return MakeElementRegion(cast<SubRegion>(newSuperR), PointeeTy, newIndex); |
| 222 | } |
| 223 | } |
| 224 | |
| 225 | llvm_unreachable("unreachable"); |
| 226 | } |
| 227 | |
| 228 | static bool regionMatchesCXXRecordType(SVal V, QualType Ty) { |
| 229 | const MemRegion *MR = V.getAsRegion(); |
| 230 | if (!MR) |
| 231 | return true; |
| 232 | |
| 233 | const auto *TVR = dyn_cast<TypedValueRegion>(MR); |
| 234 | if (!TVR) |
| 235 | return true; |
| 236 | |
| 237 | const CXXRecordDecl *RD = TVR->getValueType()->getAsCXXRecordDecl(); |
| 238 | if (!RD) |
| 239 | return true; |
| 240 | |
| 241 | const CXXRecordDecl *Expected = Ty->getPointeeCXXRecordDecl(); |
| 242 | if (!Expected) |
| 243 | Expected = Ty->getAsCXXRecordDecl(); |
| 244 | |
| 245 | return Expected->getCanonicalDecl() == RD->getCanonicalDecl(); |
| 246 | } |
| 247 | |
| 248 | SVal StoreManager::evalDerivedToBase(SVal Derived, const CastExpr *Cast) { |
| 249 | |
| 250 | |
| 251 | if (!regionMatchesCXXRecordType(Derived, Cast->getSubExpr()->getType())) |
| 252 | return UnknownVal(); |
| 253 | |
| 254 | |
| 255 | SVal Result = Derived; |
| 256 | for (CastExpr::path_const_iterator I = Cast->path_begin(), |
| 257 | E = Cast->path_end(); |
| 258 | I != E; ++I) { |
| 259 | Result = evalDerivedToBase(Result, (*I)->getType(), (*I)->isVirtual()); |
| 260 | } |
| 261 | return Result; |
| 262 | } |
| 263 | |
| 264 | SVal StoreManager::evalDerivedToBase(SVal Derived, const CXXBasePath &Path) { |
| 265 | |
| 266 | SVal Result = Derived; |
| 267 | for (const auto &I : Path) |
| 268 | Result = evalDerivedToBase(Result, I.Base->getType(), |
| 269 | I.Base->isVirtual()); |
| 270 | return Result; |
| 271 | } |
| 272 | |
| 273 | SVal StoreManager::evalDerivedToBase(SVal Derived, QualType BaseType, |
| 274 | bool IsVirtual) { |
| 275 | const MemRegion *DerivedReg = Derived.getAsRegion(); |
| 276 | if (!DerivedReg) |
| 277 | return Derived; |
| 278 | |
| 279 | const CXXRecordDecl *BaseDecl = BaseType->getPointeeCXXRecordDecl(); |
| 280 | if (!BaseDecl) |
| 281 | BaseDecl = BaseType->getAsCXXRecordDecl(); |
| 282 | (0) . __assert_fail ("BaseDecl && \"not a C++ object?\"", "/home/seafit/code_projects/clang_source/clang/lib/StaticAnalyzer/Core/Store.cpp", 282, __PRETTY_FUNCTION__))" file_link="../../../../include/assert.h.html#88" macro="true">assert(BaseDecl && "not a C++ object?"); |
| 283 | |
| 284 | if (const auto *AlreadyDerivedReg = |
| 285 | dyn_cast<CXXDerivedObjectRegion>(DerivedReg)) { |
| 286 | if (const auto *SR = |
| 287 | dyn_cast<SymbolicRegion>(AlreadyDerivedReg->getSuperRegion())) |
| 288 | if (SR->getSymbol()->getType()->getPointeeCXXRecordDecl() == BaseDecl) |
| 289 | return loc::MemRegionVal(SR); |
| 290 | |
| 291 | DerivedReg = AlreadyDerivedReg->getSuperRegion(); |
| 292 | } |
| 293 | |
| 294 | const MemRegion *BaseReg = MRMgr.getCXXBaseObjectRegion( |
| 295 | BaseDecl, cast<SubRegion>(DerivedReg), IsVirtual); |
| 296 | |
| 297 | return loc::MemRegionVal(BaseReg); |
| 298 | } |
| 299 | |
| 300 | |
| 301 | |
| 302 | |
| 303 | |
| 304 | |
| 305 | |
| 306 | static const CXXRecordDecl *getCXXRecordType(const MemRegion *MR) { |
| 307 | if (const auto *TVR = dyn_cast<TypedValueRegion>(MR)) |
| 308 | return TVR->getValueType()->getAsCXXRecordDecl(); |
| 309 | if (const auto *SR = dyn_cast<SymbolicRegion>(MR)) |
| 310 | return SR->getSymbol()->getType()->getPointeeCXXRecordDecl(); |
| 311 | return nullptr; |
| 312 | } |
| 313 | |
| 314 | SVal StoreManager::attemptDownCast(SVal Base, QualType TargetType, |
| 315 | bool &Failed) { |
| 316 | Failed = false; |
| 317 | |
| 318 | const MemRegion *MR = Base.getAsRegion(); |
| 319 | if (!MR) |
| 320 | return UnknownVal(); |
| 321 | |
| 322 | |
| 323 | TargetType = TargetType->getPointeeType(); |
| 324 | assert(!TargetType.isNull()); |
| 325 | const CXXRecordDecl *TargetClass = TargetType->getAsCXXRecordDecl(); |
| 326 | if (!TargetClass && !TargetType->isVoidType()) |
| 327 | return UnknownVal(); |
| 328 | |
| 329 | |
| 330 | |
| 331 | while (const CXXRecordDecl *MRClass = getCXXRecordType(MR)) { |
| 332 | |
| 333 | if (MRClass == TargetClass) |
| 334 | return loc::MemRegionVal(MR); |
| 335 | |
| 336 | |
| 337 | |
| 338 | |
| 339 | if (!TargetType->isVoidType() && MRClass->hasDefinition()) { |
| 340 | |
| 341 | |
| 342 | CXXBasePaths Paths(, , |
| 343 | ); |
| 344 | if (MRClass->isDerivedFrom(TargetClass, Paths)) |
| 345 | return evalDerivedToBase(loc::MemRegionVal(MR), Paths.front()); |
| 346 | } |
| 347 | |
| 348 | if (const auto *BaseR = dyn_cast<CXXBaseObjectRegion>(MR)) { |
| 349 | |
| 350 | MR = BaseR->getSuperRegion(); |
| 351 | continue; |
| 352 | } |
| 353 | |
| 354 | |
| 355 | if (TargetType->isVoidType()) |
| 356 | return loc::MemRegionVal(MR); |
| 357 | |
| 358 | |
| 359 | |
| 360 | |
| 361 | |
| 362 | |
| 363 | |
| 364 | |
| 365 | |
| 366 | const MemRegion *Uncasted = MR->StripCasts(); |
| 367 | if (Uncasted == MR) { |
| 368 | |
| 369 | |
| 370 | |
| 371 | break; |
| 372 | } |
| 373 | |
| 374 | MR = Uncasted; |
| 375 | } |
| 376 | |
| 377 | |
| 378 | |
| 379 | |
| 380 | |
| 381 | |
| 382 | if (const auto *SR = dyn_cast<SymbolicRegion>(MR)) { |
| 383 | QualType T = SR->getSymbol()->getType(); |
| 384 | const CXXRecordDecl *SourceClass = T->getPointeeCXXRecordDecl(); |
| 385 | if (TargetClass && SourceClass && TargetClass->isDerivedFrom(SourceClass)) |
| 386 | return loc::MemRegionVal( |
| 387 | MRMgr.getCXXDerivedObjectRegion(TargetClass, SR)); |
| 388 | return loc::MemRegionVal(GetElementZeroRegion(SR, TargetType)); |
| 389 | } |
| 390 | |
| 391 | |
| 392 | Failed = isa<TypedValueRegion>(MR); |
| 393 | return UnknownVal(); |
| 394 | } |
| 395 | |
| 396 | |
| 397 | |
| 398 | |
| 399 | SVal StoreManager::CastRetrievedVal(SVal V, const TypedValueRegion *R, |
| 400 | QualType castTy) { |
| 401 | if (castTy.isNull() || V.isUnknownOrUndef()) |
| 402 | return V; |
| 403 | |
| 404 | |
| 405 | |
| 406 | |
| 407 | |
| 408 | |
| 409 | if (castTy->isFloatingType()) { |
| 410 | SymbolRef Sym = V.getAsSymbol(); |
| 411 | if (Sym && !Sym->getType()->isFloatingType()) |
| 412 | return UnknownVal(); |
| 413 | } |
| 414 | |
| 415 | |
| 416 | |
| 417 | |
| 418 | |
| 419 | |
| 420 | |
| 421 | |
| 422 | |
| 423 | if (castTy->isPointerType() && !castTy->isVoidPointerType()) |
| 424 | if (const auto *SR = dyn_cast_or_null<SymbolicRegion>(V.getAsRegion())) |
| 425 | if (SR->getSymbol()->getType().getCanonicalType() != |
| 426 | castTy.getCanonicalType()) |
| 427 | return loc::MemRegionVal(castRegion(SR, castTy)); |
| 428 | |
| 429 | return svalBuilder.dispatchCast(V, castTy); |
| 430 | } |
| 431 | |
| 432 | SVal StoreManager::getLValueFieldOrIvar(const Decl *D, SVal Base) { |
| 433 | if (Base.isUnknownOrUndef()) |
| 434 | return Base; |
| 435 | |
| 436 | Loc BaseL = Base.castAs<Loc>(); |
| 437 | const SubRegion* BaseR = nullptr; |
| 438 | |
| 439 | switch (BaseL.getSubKind()) { |
| 440 | case loc::MemRegionValKind: |
| 441 | BaseR = cast<SubRegion>(BaseL.castAs<loc::MemRegionVal>().getRegion()); |
| 442 | break; |
| 443 | |
| 444 | case loc::GotoLabelKind: |
| 445 | |
| 446 | return UndefinedVal(); |
| 447 | |
| 448 | case loc::ConcreteIntKind: |
| 449 | |
| 450 | |
| 451 | |
| 452 | |
| 453 | |
| 454 | |
| 455 | |
| 456 | |
| 457 | |
| 458 | |
| 459 | return Base; |
| 460 | |
| 461 | default: |
| 462 | llvm_unreachable("Unhandled Base."); |
| 463 | } |
| 464 | |
| 465 | |
| 466 | |
| 467 | if (const auto *ID = dyn_cast<ObjCIvarDecl>(D)) |
| 468 | return loc::MemRegionVal(MRMgr.getObjCIvarRegion(ID, BaseR)); |
| 469 | |
| 470 | return loc::MemRegionVal(MRMgr.getFieldRegion(cast<FieldDecl>(D), BaseR)); |
| 471 | } |
| 472 | |
| 473 | SVal StoreManager::getLValueIvar(const ObjCIvarDecl *decl, SVal base) { |
| 474 | return getLValueFieldOrIvar(decl, base); |
| 475 | } |
| 476 | |
| 477 | SVal StoreManager::getLValueElement(QualType elementType, NonLoc Offset, |
| 478 | SVal Base) { |
| 479 | |
| 480 | |
| 481 | |
| 482 | |
| 483 | if (Base.isUnknownOrUndef() || Base.getAs<loc::ConcreteInt>()) |
| 484 | return Base; |
| 485 | |
| 486 | if (Base.getAs<loc::GotoLabel>()) |
| 487 | return UnknownVal(); |
| 488 | |
| 489 | const SubRegion *BaseRegion = |
| 490 | Base.castAs<loc::MemRegionVal>().getRegionAs<SubRegion>(); |
| 491 | |
| 492 | |
| 493 | const auto *ElemR = dyn_cast<ElementRegion>(BaseRegion); |
| 494 | |
| 495 | |
| 496 | Offset = svalBuilder.convertToArrayIndex(Offset).castAs<NonLoc>(); |
| 497 | |
| 498 | if (!ElemR) { |
| 499 | |
| 500 | |
| 501 | |
| 502 | |
| 503 | |
| 504 | |
| 505 | |
| 506 | return loc::MemRegionVal(MRMgr.getElementRegion(elementType, Offset, |
| 507 | BaseRegion, Ctx)); |
| 508 | } |
| 509 | |
| 510 | SVal BaseIdx = ElemR->getIndex(); |
| 511 | |
| 512 | if (!BaseIdx.getAs<nonloc::ConcreteInt>()) |
| 513 | return UnknownVal(); |
| 514 | |
| 515 | const llvm::APSInt &BaseIdxI = |
| 516 | BaseIdx.castAs<nonloc::ConcreteInt>().getValue(); |
| 517 | |
| 518 | |
| 519 | |
| 520 | |
| 521 | if (!Offset.getAs<nonloc::ConcreteInt>()) { |
| 522 | if (isa<ElementRegion>(BaseRegion->StripCasts())) |
| 523 | return UnknownVal(); |
| 524 | |
| 525 | return loc::MemRegionVal(MRMgr.getElementRegion( |
| 526 | elementType, Offset, cast<SubRegion>(ElemR->getSuperRegion()), Ctx)); |
| 527 | } |
| 528 | |
| 529 | const llvm::APSInt& OffI = Offset.castAs<nonloc::ConcreteInt>().getValue(); |
| 530 | assert(BaseIdxI.isSigned()); |
| 531 | |
| 532 | |
| 533 | nonloc::ConcreteInt NewIdx(svalBuilder.getBasicValueFactory().getValue(BaseIdxI + |
| 534 | OffI)); |
| 535 | |
| 536 | |
| 537 | const SubRegion *ArrayR = cast<SubRegion>(ElemR->getSuperRegion()); |
| 538 | return loc::MemRegionVal(MRMgr.getElementRegion(elementType, NewIdx, ArrayR, |
| 539 | Ctx)); |
| 540 | } |
| 541 | |
| 542 | StoreManager::BindingsHandler::~BindingsHandler() = default; |
| 543 | |
| 544 | bool StoreManager::FindUniqueBinding::HandleBinding(StoreManager& SMgr, |
| 545 | Store store, |
| 546 | const MemRegion* R, |
| 547 | SVal val) { |
| 548 | SymbolRef SymV = val.getAsLocSymbol(); |
| 549 | if (!SymV || SymV != Sym) |
| 550 | return true; |
| 551 | |
| 552 | if (Binding) { |
| 553 | First = false; |
| 554 | return false; |
| 555 | } |
| 556 | else |
| 557 | Binding = R; |
| 558 | |
| 559 | return true; |
| 560 | } |
| 561 | |