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Diffstat (limited to 'contrib/llvm-project/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp')
| -rw-r--r-- | contrib/llvm-project/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp | 1287 |
1 files changed, 776 insertions, 511 deletions
diff --git a/contrib/llvm-project/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp b/contrib/llvm-project/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp index a79b34189065..a82449951873 100644 --- a/contrib/llvm-project/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp +++ b/contrib/llvm-project/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp @@ -6,8 +6,41 @@ // //===----------------------------------------------------------------------===// // -// This file defines malloc/free checker, which checks for potential memory -// leaks, double free, and use-after-free problems. +// This file defines a variety of memory management related checkers, such as +// leak, double free, and use-after-free. +// +// The following checkers are defined here: +// +// * MallocChecker +// Despite its name, it models all sorts of memory allocations and +// de- or reallocation, including but not limited to malloc, free, +// relloc, new, delete. It also reports on a variety of memory misuse +// errors. +// Many other checkers interact very closely with this checker, in fact, +// most are merely options to this one. Other checkers may register +// MallocChecker, but do not enable MallocChecker's reports (more details +// to follow around its field, ChecksEnabled). +// It also has a boolean "Optimistic" checker option, which if set to true +// will cause the checker to model user defined memory management related +// functions annotated via the attribute ownership_takes, ownership_holds +// and ownership_returns. +// +// * NewDeleteChecker +// Enables the modeling of new, new[], delete, delete[] in MallocChecker, +// and checks for related double-free and use-after-free errors. +// +// * NewDeleteLeaksChecker +// Checks for leaks related to new, new[], delete, delete[]. +// Depends on NewDeleteChecker. +// +// * MismatchedDeallocatorChecker +// Enables checking whether memory is deallocated with the correspending +// allocation function in MallocChecker, such as malloc() allocated +// regions are only freed by free(), new by delete, new[] by delete[]. +// +// InnerPointerChecker interacts very closely with MallocChecker, but unlike +// the above checkers, it has it's own file, hence the many InnerPointerChecker +// related headers and non-static functions. // //===----------------------------------------------------------------------===// @@ -37,6 +70,10 @@ using namespace clang; using namespace ento; +//===----------------------------------------------------------------------===// +// The types of allocation we're modeling. +//===----------------------------------------------------------------------===// + namespace { // Used to check correspondence between allocators and deallocators. @@ -50,57 +87,88 @@ enum AllocationFamily { AF_InnerBuffer }; +struct MemFunctionInfoTy; + +} // end of anonymous namespace + +/// Determine family of a deallocation expression. +static AllocationFamily +getAllocationFamily(const MemFunctionInfoTy &MemFunctionInfo, CheckerContext &C, + const Stmt *S); + +/// Print names of allocators and deallocators. +/// +/// \returns true on success. +static bool printAllocDeallocName(raw_ostream &os, CheckerContext &C, + const Expr *E); + +/// Print expected name of an allocator based on the deallocator's +/// family derived from the DeallocExpr. +static void printExpectedAllocName(raw_ostream &os, + const MemFunctionInfoTy &MemFunctionInfo, + CheckerContext &C, const Expr *E); + +/// Print expected name of a deallocator based on the allocator's +/// family. +static void printExpectedDeallocName(raw_ostream &os, AllocationFamily Family); + +//===----------------------------------------------------------------------===// +// The state of a symbol, in terms of memory management. +//===----------------------------------------------------------------------===// + +namespace { + class RefState { - enum Kind { // Reference to allocated memory. - Allocated, - // Reference to zero-allocated memory. - AllocatedOfSizeZero, - // Reference to released/freed memory. - Released, - // The responsibility for freeing resources has transferred from - // this reference. A relinquished symbol should not be freed. - Relinquished, - // We are no longer guaranteed to have observed all manipulations - // of this pointer/memory. For example, it could have been - // passed as a parameter to an opaque function. - Escaped + enum Kind { + // Reference to allocated memory. + Allocated, + // Reference to zero-allocated memory. + AllocatedOfSizeZero, + // Reference to released/freed memory. + Released, + // The responsibility for freeing resources has transferred from + // this reference. A relinquished symbol should not be freed. + Relinquished, + // We are no longer guaranteed to have observed all manipulations + // of this pointer/memory. For example, it could have been + // passed as a parameter to an opaque function. + Escaped }; const Stmt *S; - unsigned K : 3; // Kind enum, but stored as a bitfield. - unsigned Family : 29; // Rest of 32-bit word, currently just an allocation - // family. - RefState(Kind k, const Stmt *s, unsigned family) - : S(s), K(k), Family(family) { + Kind K; + AllocationFamily Family; + + RefState(Kind k, const Stmt *s, AllocationFamily family) + : S(s), K(k), Family(family) { assert(family != AF_None); } + public: bool isAllocated() const { return K == Allocated; } bool isAllocatedOfSizeZero() const { return K == AllocatedOfSizeZero; } bool isReleased() const { return K == Released; } bool isRelinquished() const { return K == Relinquished; } bool isEscaped() const { return K == Escaped; } - AllocationFamily getAllocationFamily() const { - return (AllocationFamily)Family; - } + AllocationFamily getAllocationFamily() const { return Family; } const Stmt *getStmt() const { return S; } bool operator==(const RefState &X) const { return K == X.K && S == X.S && Family == X.Family; } - static RefState getAllocated(unsigned family, const Stmt *s) { + static RefState getAllocated(AllocationFamily family, const Stmt *s) { return RefState(Allocated, s, family); } static RefState getAllocatedOfSizeZero(const RefState *RS) { return RefState(AllocatedOfSizeZero, RS->getStmt(), RS->getAllocationFamily()); } - static RefState getReleased(unsigned family, const Stmt *s) { + static RefState getReleased(AllocationFamily family, const Stmt *s) { return RefState(Released, s, family); } - static RefState getRelinquished(unsigned family, const Stmt *s) { + static RefState getRelinquished(AllocationFamily family, const Stmt *s) { return RefState(Relinquished, s, family); } static RefState getEscaped(const RefState *RS) { @@ -113,8 +181,8 @@ public: ID.AddInteger(Family); } - void dump(raw_ostream &OS) const { - switch (static_cast<Kind>(K)) { + LLVM_DUMP_METHOD void dump(raw_ostream &OS) const { + switch (K) { #define CASE(ID) case ID: OS << #ID; break; CASE(Allocated) CASE(AllocatedOfSizeZero) @@ -127,24 +195,62 @@ public: LLVM_DUMP_METHOD void dump() const { dump(llvm::errs()); } }; -enum ReallocPairKind { - RPToBeFreedAfterFailure, - // The symbol has been freed when reallocation failed. - RPIsFreeOnFailure, - // The symbol does not need to be freed after reallocation fails. - RPDoNotTrackAfterFailure +} // end of anonymous namespace + +REGISTER_MAP_WITH_PROGRAMSTATE(RegionState, SymbolRef, RefState) + +/// Check if the memory associated with this symbol was released. +static bool isReleased(SymbolRef Sym, CheckerContext &C); + +/// Update the RefState to reflect the new memory allocation. +/// The optional \p RetVal parameter specifies the newly allocated pointer +/// value; if unspecified, the value of expression \p E is used. +static ProgramStateRef MallocUpdateRefState(CheckerContext &C, const Expr *E, + ProgramStateRef State, + AllocationFamily Family = AF_Malloc, + Optional<SVal> RetVal = None); + +//===----------------------------------------------------------------------===// +// The modeling of memory reallocation. +// +// The terminology 'toPtr' and 'fromPtr' will be used: +// toPtr = realloc(fromPtr, 20); +//===----------------------------------------------------------------------===// + +REGISTER_SET_WITH_PROGRAMSTATE(ReallocSizeZeroSymbols, SymbolRef) + +namespace { + +/// The state of 'fromPtr' after reallocation is known to have failed. +enum OwnershipAfterReallocKind { + // The symbol needs to be freed (e.g.: realloc) + OAR_ToBeFreedAfterFailure, + // The symbol has been freed (e.g.: reallocf) + OAR_FreeOnFailure, + // The symbol doesn't have to freed (e.g.: we aren't sure if, how and where + // 'fromPtr' was allocated: + // void Haha(int *ptr) { + // ptr = realloc(ptr, 67); + // // ... + // } + // ). + OAR_DoNotTrackAfterFailure }; -/// \class ReallocPair -/// Stores information about the symbol being reallocated by a call to -/// 'realloc' to allow modeling failed reallocation later in the path. +/// Stores information about the 'fromPtr' symbol after reallocation. +/// +/// This is important because realloc may fail, and that needs special modeling. +/// Whether reallocation failed or not will not be known until later, so we'll +/// store whether upon failure 'fromPtr' will be freed, or needs to be freed +/// later, etc. struct ReallocPair { - // The symbol which realloc reallocated. + + // The 'fromPtr'. SymbolRef ReallocatedSym; - ReallocPairKind Kind; + OwnershipAfterReallocKind Kind; - ReallocPair(SymbolRef S, ReallocPairKind K) : - ReallocatedSym(S), Kind(K) {} + ReallocPair(SymbolRef S, OwnershipAfterReallocKind K) + : ReallocatedSym(S), Kind(K) {} void Profile(llvm::FoldingSetNodeID &ID) const { ID.AddInteger(Kind); ID.AddPointer(ReallocatedSym); @@ -155,42 +261,88 @@ struct ReallocPair { } }; -typedef std::pair<const ExplodedNode*, const MemRegion*> LeakInfo; - -class MallocChecker : public Checker<check::DeadSymbols, - check::PointerEscape, - check::ConstPointerEscape, - check::PreStmt<ReturnStmt>, - check::EndFunction, - check::PreCall, - check::PostStmt<CallExpr>, - check::PostStmt<CXXNewExpr>, - check::NewAllocator, - check::PreStmt<CXXDeleteExpr>, - check::PostStmt<BlockExpr>, - check::PostObjCMessage, - check::Location, - eval::Assume> -{ -public: - MallocChecker() - : II_alloca(nullptr), II_win_alloca(nullptr), II_malloc(nullptr), - II_free(nullptr), II_realloc(nullptr), II_calloc(nullptr), - II_valloc(nullptr), II_reallocf(nullptr), II_strndup(nullptr), - II_strdup(nullptr), II_win_strdup(nullptr), II_kmalloc(nullptr), - II_kfree(nullptr), II_if_nameindex(nullptr), - II_if_freenameindex(nullptr), II_wcsdup(nullptr), - II_win_wcsdup(nullptr), II_g_malloc(nullptr), II_g_malloc0(nullptr), - II_g_realloc(nullptr), II_g_try_malloc(nullptr), - II_g_try_malloc0(nullptr), II_g_try_realloc(nullptr), - II_g_free(nullptr), II_g_memdup(nullptr), II_g_malloc_n(nullptr), - II_g_malloc0_n(nullptr), II_g_realloc_n(nullptr), - II_g_try_malloc_n(nullptr), II_g_try_malloc0_n(nullptr), - II_g_try_realloc_n(nullptr) {} +} // end of anonymous namespace + +REGISTER_MAP_WITH_PROGRAMSTATE(ReallocPairs, SymbolRef, ReallocPair) + +//===----------------------------------------------------------------------===// +// Kinds of memory operations, information about resource managing functions. +//===----------------------------------------------------------------------===// + +namespace { + +enum class MemoryOperationKind { MOK_Allocate, MOK_Free, MOK_Any }; +struct MemFunctionInfoTy { + /// The value of the MallocChecker:Optimistic is stored in this variable. + /// /// In pessimistic mode, the checker assumes that it does not know which /// functions might free the memory. + /// In optimistic mode, the checker assumes that all user-defined functions + /// which might free a pointer are annotated. + DefaultBool ShouldIncludeOwnershipAnnotatedFunctions; + + // TODO: Change these to CallDescription, and get rid of lazy initialization. + mutable IdentifierInfo *II_alloca = nullptr, *II_win_alloca = nullptr, + *II_malloc = nullptr, *II_free = nullptr, + *II_realloc = nullptr, *II_calloc = nullptr, + *II_valloc = nullptr, *II_reallocf = nullptr, + *II_strndup = nullptr, *II_strdup = nullptr, + *II_win_strdup = nullptr, *II_kmalloc = nullptr, + *II_if_nameindex = nullptr, + *II_if_freenameindex = nullptr, *II_wcsdup = nullptr, + *II_win_wcsdup = nullptr, *II_g_malloc = nullptr, + *II_g_malloc0 = nullptr, *II_g_realloc = nullptr, + *II_g_try_malloc = nullptr, + *II_g_try_malloc0 = nullptr, + *II_g_try_realloc = nullptr, *II_g_free = nullptr, + *II_g_memdup = nullptr, *II_g_malloc_n = nullptr, + *II_g_malloc0_n = nullptr, *II_g_realloc_n = nullptr, + *II_g_try_malloc_n = nullptr, + *II_g_try_malloc0_n = nullptr, *II_kfree = nullptr, + *II_g_try_realloc_n = nullptr; + + void initIdentifierInfo(ASTContext &C) const; + + ///@{ + /// Check if this is one of the functions which can allocate/reallocate + /// memory pointed to by one of its arguments. + bool isMemFunction(const FunctionDecl *FD, ASTContext &C) const; + bool isCMemFunction(const FunctionDecl *FD, ASTContext &C, + AllocationFamily Family, + MemoryOperationKind MemKind) const; + + /// Tells if the callee is one of the builtin new/delete operators, including + /// placement operators and other standard overloads. + bool isStandardNewDelete(const FunctionDecl *FD, ASTContext &C) const; + ///@} +}; + +} // end of anonymous namespace + +//===----------------------------------------------------------------------===// +// Definition of the MallocChecker class. +//===----------------------------------------------------------------------===// + +namespace { + +class MallocChecker + : public Checker<check::DeadSymbols, check::PointerEscape, + check::ConstPointerEscape, check::PreStmt<ReturnStmt>, + check::EndFunction, check::PreCall, + check::PostStmt<CallExpr>, check::PostStmt<CXXNewExpr>, + check::NewAllocator, check::PreStmt<CXXDeleteExpr>, + check::PostStmt<BlockExpr>, check::PostObjCMessage, + check::Location, eval::Assume> { +public: + MemFunctionInfoTy MemFunctionInfo; + + /// Many checkers are essentially built into this one, so enabling them will + /// make MallocChecker perform additional modeling and reporting. enum CheckKind { + /// When a subchecker is enabled but MallocChecker isn't, model memory + /// management but do not emit warnings emitted with MallocChecker only + /// enabled. CK_MallocChecker, CK_NewDeleteChecker, CK_NewDeleteLeaksChecker, @@ -199,16 +351,10 @@ public: CK_NumCheckKinds }; - enum class MemoryOperationKind { - MOK_Allocate, - MOK_Free, - MOK_Any - }; - - DefaultBool IsOptimistic; + using LeakInfo = std::pair<const ExplodedNode *, const MemRegion *>; DefaultBool ChecksEnabled[CK_NumCheckKinds]; - CheckName CheckNames[CK_NumCheckKinds]; + CheckerNameRef CheckNames[CK_NumCheckKinds]; void checkPreCall(const CallEvent &Call, CheckerContext &C) const; void checkPostStmt(const CallExpr *CE, CheckerContext &C) const; @@ -248,47 +394,9 @@ private: mutable std::unique_ptr<BugType> BT_MismatchedDealloc; mutable std::unique_ptr<BugType> BT_OffsetFree[CK_NumCheckKinds]; mutable std::unique_ptr<BugType> BT_UseZerroAllocated[CK_NumCheckKinds]; - mutable IdentifierInfo *II_alloca, *II_win_alloca, *II_malloc, *II_free, - *II_realloc, *II_calloc, *II_valloc, *II_reallocf, - *II_strndup, *II_strdup, *II_win_strdup, *II_kmalloc, - *II_kfree, *II_if_nameindex, *II_if_freenameindex, - *II_wcsdup, *II_win_wcsdup, *II_g_malloc, - *II_g_malloc0, *II_g_realloc, *II_g_try_malloc, - *II_g_try_malloc0, *II_g_try_realloc, *II_g_free, - *II_g_memdup, *II_g_malloc_n, *II_g_malloc0_n, - *II_g_realloc_n, *II_g_try_malloc_n, - *II_g_try_malloc0_n, *II_g_try_realloc_n; - mutable Optional<uint64_t> KernelZeroFlagVal; - - void initIdentifierInfo(ASTContext &C) const; - - /// Determine family of a deallocation expression. - AllocationFamily getAllocationFamily(CheckerContext &C, const Stmt *S) const; - - /// Print names of allocators and deallocators. - /// - /// \returns true on success. - bool printAllocDeallocName(raw_ostream &os, CheckerContext &C, - const Expr *E) const; - - /// Print expected name of an allocator based on the deallocator's - /// family derived from the DeallocExpr. - void printExpectedAllocName(raw_ostream &os, CheckerContext &C, - const Expr *DeallocExpr) const; - /// Print expected name of a deallocator based on the allocator's - /// family. - void printExpectedDeallocName(raw_ostream &os, AllocationFamily Family) const; - ///@{ - /// Check if this is one of the functions which can allocate/reallocate memory - /// pointed to by one of its arguments. - bool isMemFunction(const FunctionDecl *FD, ASTContext &C) const; - bool isCMemFunction(const FunctionDecl *FD, - ASTContext &C, - AllocationFamily Family, - MemoryOperationKind MemKind) const; - bool isStandardNewDelete(const FunctionDecl *FD, ASTContext &C) const; - ///@} + // TODO: Remove mutable by moving the initializtaion to the registry function. + mutable Optional<uint64_t> KernelZeroFlagVal; /// Process C++ operator new()'s allocation, which is the part of C++ /// new-expression that goes before the constructor. @@ -296,23 +404,64 @@ private: SVal Target) const; /// Perform a zero-allocation check. - /// The optional \p RetVal parameter specifies the newly allocated pointer - /// value; if unspecified, the value of expression \p E is used. - ProgramStateRef ProcessZeroAllocation(CheckerContext &C, const Expr *E, - const unsigned AllocationSizeArg, - ProgramStateRef State, - Optional<SVal> RetVal = None) const; - + /// + /// \param [in] E The expression that allocates memory. + /// \param [in] IndexOfSizeArg Index of the argument that specifies the size + /// of the memory that needs to be allocated. E.g. for malloc, this would be + /// 0. + /// \param [in] RetVal Specifies the newly allocated pointer value; + /// if unspecified, the value of expression \p E is used. + static ProgramStateRef ProcessZeroAllocCheck(CheckerContext &C, const Expr *E, + const unsigned IndexOfSizeArg, + ProgramStateRef State, + Optional<SVal> RetVal = None); + + /// Model functions with the ownership_returns attribute. + /// + /// User-defined function may have the ownership_returns attribute, which + /// annotates that the function returns with an object that was allocated on + /// the heap, and passes the ownertship to the callee. + /// + /// void __attribute((ownership_returns(malloc, 1))) *my_malloc(size_t); + /// + /// It has two parameters: + /// - first: name of the resource (e.g. 'malloc') + /// - (OPTIONAL) second: size of the allocated region + /// + /// \param [in] CE The expression that allocates memory. + /// \param [in] Att The ownership_returns attribute. + /// \param [in] State The \c ProgramState right before allocation. + /// \returns The ProgramState right after allocation. ProgramStateRef MallocMemReturnsAttr(CheckerContext &C, const CallExpr *CE, const OwnershipAttr* Att, ProgramStateRef State) const; + + /// Models memory allocation. + /// + /// \param [in] CE The expression that allocates memory. + /// \param [in] SizeEx Size of the memory that needs to be allocated. + /// \param [in] Init The value the allocated memory needs to be initialized. + /// with. For example, \c calloc initializes the allocated memory to 0, + /// malloc leaves it undefined. + /// \param [in] State The \c ProgramState right before allocation. + /// \returns The ProgramState right after allocation. static ProgramStateRef MallocMemAux(CheckerContext &C, const CallExpr *CE, const Expr *SizeEx, SVal Init, ProgramStateRef State, AllocationFamily Family = AF_Malloc); + + /// Models memory allocation. + /// + /// \param [in] CE The expression that allocates memory. + /// \param [in] Size Size of the memory that needs to be allocated. + /// \param [in] Init The value the allocated memory needs to be initialized. + /// with. For example, \c calloc initializes the allocated memory to 0, + /// malloc leaves it undefined. + /// \param [in] State The \c ProgramState right before allocation. + /// \returns The ProgramState right after allocation. static ProgramStateRef MallocMemAux(CheckerContext &C, const CallExpr *CE, - SVal SizeEx, SVal Init, + SVal Size, SVal Init, ProgramStateRef State, AllocationFamily Family = AF_Malloc); @@ -325,54 +474,125 @@ private: performKernelMalloc(const CallExpr *CE, CheckerContext &C, const ProgramStateRef &State) const; - /// Update the RefState to reflect the new memory allocation. - /// The optional \p RetVal parameter specifies the newly allocated pointer - /// value; if unspecified, the value of expression \p E is used. - static ProgramStateRef - MallocUpdateRefState(CheckerContext &C, const Expr *E, ProgramStateRef State, - AllocationFamily Family = AF_Malloc, - Optional<SVal> RetVal = None); - + /// Model functions with the ownership_takes and ownership_holds attributes. + /// + /// User-defined function may have the ownership_takes and/or ownership_holds + /// attributes, which annotates that the function frees the memory passed as a + /// parameter. + /// + /// void __attribute((ownership_takes(malloc, 1))) my_free(void *); + /// void __attribute((ownership_holds(malloc, 1))) my_hold(void *); + /// + /// They have two parameters: + /// - first: name of the resource (e.g. 'malloc') + /// - second: index of the parameter the attribute applies to + /// + /// \param [in] CE The expression that frees memory. + /// \param [in] Att The ownership_takes or ownership_holds attribute. + /// \param [in] State The \c ProgramState right before allocation. + /// \returns The ProgramState right after deallocation. ProgramStateRef FreeMemAttr(CheckerContext &C, const CallExpr *CE, const OwnershipAttr* Att, ProgramStateRef State) const; + + /// Models memory deallocation. + /// + /// \param [in] CE The expression that frees memory. + /// \param [in] State The \c ProgramState right before allocation. + /// \param [in] Num Index of the argument that needs to be freed. This is + /// normally 0, but for custom free functions it may be different. + /// \param [in] Hold Whether the parameter at \p Index has the ownership_holds + /// attribute. + /// \param [out] IsKnownToBeAllocated Whether the memory to be freed is known + /// to have been allocated, or in other words, the symbol to be freed was + /// registered as allocated by this checker. In the following case, \c ptr + /// isn't known to be allocated. + /// void Haha(int *ptr) { + /// ptr = realloc(ptr, 67); + /// // ... + /// } + /// \param [in] ReturnsNullOnFailure Whether the memory deallocation function + /// we're modeling returns with Null on failure. + /// \returns The ProgramState right after deallocation. ProgramStateRef FreeMemAux(CheckerContext &C, const CallExpr *CE, - ProgramStateRef state, unsigned Num, - bool Hold, - bool &ReleasedAllocated, + ProgramStateRef State, unsigned Num, bool Hold, + bool &IsKnownToBeAllocated, bool ReturnsNullOnFailure = false) const; - ProgramStateRef FreeMemAux(CheckerContext &C, const Expr *Arg, - const Expr *ParentExpr, - ProgramStateRef State, - bool Hold, - bool &ReleasedAllocated, + + /// Models memory deallocation. + /// + /// \param [in] ArgExpr The variable who's pointee needs to be freed. + /// \param [in] ParentExpr The expression that frees the memory. + /// \param [in] State The \c ProgramState right before allocation. + /// normally 0, but for custom free functions it may be different. + /// \param [in] Hold Whether the parameter at \p Index has the ownership_holds + /// attribute. + /// \param [out] IsKnownToBeAllocated Whether the memory to be freed is known + /// to have been allocated, or in other words, the symbol to be freed was + /// registered as allocated by this checker. In the following case, \c ptr + /// isn't known to be allocated. + /// void Haha(int *ptr) { + /// ptr = realloc(ptr, 67); + /// // ... + /// } + /// \param [in] ReturnsNullOnFailure Whether the memory deallocation function + /// we're modeling returns with Null on failure. + /// \returns The ProgramState right after deallocation. + ProgramStateRef FreeMemAux(CheckerContext &C, const Expr *ArgExpr, + const Expr *ParentExpr, ProgramStateRef State, + bool Hold, bool &IsKnownToBeAllocated, bool ReturnsNullOnFailure = false) const; + // TODO: Needs some refactoring, as all other deallocation modeling + // functions are suffering from out parameters and messy code due to how + // realloc is handled. + // + /// Models memory reallocation. + /// + /// \param [in] CE The expression that reallocated memory + /// \param [in] ShouldFreeOnFail Whether if reallocation fails, the supplied + /// memory should be freed. + /// \param [in] State The \c ProgramState right before reallocation. + /// \param [in] SuffixWithN Whether the reallocation function we're modeling + /// has an '_n' suffix, such as g_realloc_n. + /// \returns The ProgramState right after reallocation. ProgramStateRef ReallocMemAux(CheckerContext &C, const CallExpr *CE, - bool FreesMemOnFailure, - ProgramStateRef State, + bool ShouldFreeOnFail, ProgramStateRef State, bool SuffixWithN = false) const; + + /// Evaluates the buffer size that needs to be allocated. + /// + /// \param [in] Blocks The amount of blocks that needs to be allocated. + /// \param [in] BlockBytes The size of a block. + /// \returns The symbolic value of \p Blocks * \p BlockBytes. static SVal evalMulForBufferSize(CheckerContext &C, const Expr *Blocks, const Expr *BlockBytes); + + /// Models zero initialized array allocation. + /// + /// \param [in] CE The expression that reallocated memory + /// \param [in] State The \c ProgramState right before reallocation. + /// \returns The ProgramState right after allocation. static ProgramStateRef CallocMem(CheckerContext &C, const CallExpr *CE, ProgramStateRef State); - /// Check if the memory associated with this symbol was released. - bool isReleased(SymbolRef Sym, CheckerContext &C) const; - /// See if deallocation happens in a suspicious context. If so, escape the /// pointers that otherwise would have been deallocated and return true. bool suppressDeallocationsInSuspiciousContexts(const CallExpr *CE, CheckerContext &C) const; + /// If in \p S \p Sym is used, check whether \p Sym was already freed. bool checkUseAfterFree(SymbolRef Sym, CheckerContext &C, const Stmt *S) const; + /// If in \p S \p Sym is used, check whether \p Sym was allocated as a zero + /// sized memory region. void checkUseZeroAllocated(SymbolRef Sym, CheckerContext &C, const Stmt *S) const; + /// If in \p S \p Sym is being freed, check whether \p Sym was already freed. bool checkDoubleDelete(SymbolRef Sym, CheckerContext &C) const; - /// Check if the function is known free memory, or if it is + /// Check if the function is known to free memory, or if it is /// "interesting" and should be modeled explicitly. /// /// \param [out] EscapingSymbol A function might not free memory in general, @@ -386,12 +606,12 @@ private: ProgramStateRef State, SymbolRef &EscapingSymbol) const; - // Implementation of the checkPointerEscape callbacks. + /// Implementation of the checkPointerEscape callbacks. ProgramStateRef checkPointerEscapeAux(ProgramStateRef State, - const InvalidatedSymbols &Escaped, - const CallEvent *Call, - PointerEscapeKind Kind, - bool(*CheckRefState)(const RefState*)) const; + const InvalidatedSymbols &Escaped, + const CallEvent *Call, + PointerEscapeKind Kind, + bool IsConstPointerEscape) const; // Implementation of the checkPreStmt and checkEndFunction callbacks. void checkEscapeOnReturn(const ReturnStmt *S, CheckerContext &C) const; @@ -410,6 +630,7 @@ private: ///@} static bool SummarizeValue(raw_ostream &os, SVal V); static bool SummarizeRegion(raw_ostream &os, const MemRegion *MR); + void ReportBadFree(CheckerContext &C, SVal ArgVal, SourceRange Range, const Expr *DeallocExpr) const; void ReportFreeAlloca(CheckerContext &C, SVal ArgVal, @@ -435,143 +656,142 @@ private: /// Find the location of the allocation for Sym on the path leading to the /// exploded node N. - LeakInfo getAllocationSite(const ExplodedNode *N, SymbolRef Sym, - CheckerContext &C) const; + static LeakInfo getAllocationSite(const ExplodedNode *N, SymbolRef Sym, + CheckerContext &C); void reportLeak(SymbolRef Sym, ExplodedNode *N, CheckerContext &C) const; +}; - /// The bug visitor which allows us to print extra diagnostics along the - /// BugReport path. For example, showing the allocation site of the leaked - /// region. - class MallocBugVisitor final : public BugReporterVisitor { - protected: - enum NotificationMode { - Normal, - ReallocationFailed - }; - - // The allocated region symbol tracked by the main analysis. - SymbolRef Sym; - - // The mode we are in, i.e. what kind of diagnostics will be emitted. - NotificationMode Mode; - - // A symbol from when the primary region should have been reallocated. - SymbolRef FailedReallocSymbol; - - // A C++ destructor stack frame in which memory was released. Used for - // miscellaneous false positive suppression. - const StackFrameContext *ReleaseDestructorLC; - - bool IsLeak; - - public: - MallocBugVisitor(SymbolRef S, bool isLeak = false) - : Sym(S), Mode(Normal), FailedReallocSymbol(nullptr), - ReleaseDestructorLC(nullptr), IsLeak(isLeak) {} - - static void *getTag() { - static int Tag = 0; - return &Tag; - } +//===----------------------------------------------------------------------===// +// Definition of MallocBugVisitor. +//===----------------------------------------------------------------------===// - void Profile(llvm::FoldingSetNodeID &ID) const override { - ID.AddPointer(getTag()); - ID.AddPointer(Sym); - } +/// The bug visitor which allows us to print extra diagnostics along the +/// BugReport path. For example, showing the allocation site of the leaked +/// region. +class MallocBugVisitor final : public BugReporterVisitor { +protected: + enum NotificationMode { Normal, ReallocationFailed }; - inline bool isAllocated(const RefState *S, const RefState *SPrev, - const Stmt *Stmt) { - // Did not track -> allocated. Other state (released) -> allocated. - return (Stmt && (isa<CallExpr>(Stmt) || isa<CXXNewExpr>(Stmt)) && - (S && (S->isAllocated() || S->isAllocatedOfSizeZero())) && - (!SPrev || !(SPrev->isAllocated() || - SPrev->isAllocatedOfSizeZero()))); - } + // The allocated region symbol tracked by the main analysis. + SymbolRef Sym; - inline bool isReleased(const RefState *S, const RefState *SPrev, - const Stmt *Stmt) { - // Did not track -> released. Other state (allocated) -> released. - // The statement associated with the release might be missing. - bool IsReleased = (S && S->isReleased()) && - (!SPrev || !SPrev->isReleased()); - assert(!IsReleased || - (Stmt && (isa<CallExpr>(Stmt) || isa<CXXDeleteExpr>(Stmt))) || - (!Stmt && S->getAllocationFamily() == AF_InnerBuffer)); - return IsReleased; - } + // The mode we are in, i.e. what kind of diagnostics will be emitted. + NotificationMode Mode; - inline bool isRelinquished(const RefState *S, const RefState *SPrev, - const Stmt *Stmt) { - // Did not track -> relinquished. Other state (allocated) -> relinquished. - return (Stmt && (isa<CallExpr>(Stmt) || isa<ObjCMessageExpr>(Stmt) || - isa<ObjCPropertyRefExpr>(Stmt)) && - (S && S->isRelinquished()) && - (!SPrev || !SPrev->isRelinquished())); - } + // A symbol from when the primary region should have been reallocated. + SymbolRef FailedReallocSymbol; - inline bool isReallocFailedCheck(const RefState *S, const RefState *SPrev, - const Stmt *Stmt) { - // If the expression is not a call, and the state change is - // released -> allocated, it must be the realloc return value - // check. If we have to handle more cases here, it might be cleaner just - // to track this extra bit in the state itself. - return ((!Stmt || !isa<CallExpr>(Stmt)) && - (S && (S->isAllocated() || S->isAllocatedOfSizeZero())) && - (SPrev && !(SPrev->isAllocated() || - SPrev->isAllocatedOfSizeZero()))); - } + // A C++ destructor stack frame in which memory was released. Used for + // miscellaneous false positive suppression. + const StackFrameContext *ReleaseDestructorLC; - std::shared_ptr<PathDiagnosticPiece> VisitNode(const ExplodedNode *N, - BugReporterContext &BRC, - BugReport &BR) override; + bool IsLeak; - std::shared_ptr<PathDiagnosticPiece> - getEndPath(BugReporterContext &BRC, const ExplodedNode *EndPathNode, - BugReport &BR) override { - if (!IsLeak) - return nullptr; +public: + MallocBugVisitor(SymbolRef S, bool isLeak = false) + : Sym(S), Mode(Normal), FailedReallocSymbol(nullptr), + ReleaseDestructorLC(nullptr), IsLeak(isLeak) {} + + static void *getTag() { + static int Tag = 0; + return &Tag; + } + + void Profile(llvm::FoldingSetNodeID &ID) const override { + ID.AddPointer(getTag()); + ID.AddPointer(Sym); + } + + /// Did not track -> allocated. Other state (released) -> allocated. + static inline bool isAllocated(const RefState *RSCurr, const RefState *RSPrev, + const Stmt *Stmt) { + return (Stmt && (isa<CallExpr>(Stmt) || isa<CXXNewExpr>(Stmt)) && + (RSCurr && + (RSCurr->isAllocated() || RSCurr->isAllocatedOfSizeZero())) && + (!RSPrev || + !(RSPrev->isAllocated() || RSPrev->isAllocatedOfSizeZero()))); + } + + /// Did not track -> released. Other state (allocated) -> released. + /// The statement associated with the release might be missing. + static inline bool isReleased(const RefState *RSCurr, const RefState *RSPrev, + const Stmt *Stmt) { + bool IsReleased = + (RSCurr && RSCurr->isReleased()) && (!RSPrev || !RSPrev->isReleased()); + assert(!IsReleased || + (Stmt && (isa<CallExpr>(Stmt) || isa<CXXDeleteExpr>(Stmt))) || + (!Stmt && RSCurr->getAllocationFamily() == AF_InnerBuffer)); + return IsReleased; + } + + /// Did not track -> relinquished. Other state (allocated) -> relinquished. + static inline bool isRelinquished(const RefState *RSCurr, + const RefState *RSPrev, const Stmt *Stmt) { + return (Stmt && + (isa<CallExpr>(Stmt) || isa<ObjCMessageExpr>(Stmt) || + isa<ObjCPropertyRefExpr>(Stmt)) && + (RSCurr && RSCurr->isRelinquished()) && + (!RSPrev || !RSPrev->isRelinquished())); + } + + /// If the expression is not a call, and the state change is + /// released -> allocated, it must be the realloc return value + /// check. If we have to handle more cases here, it might be cleaner just + /// to track this extra bit in the state itself. + static inline bool hasReallocFailed(const RefState *RSCurr, + const RefState *RSPrev, + const Stmt *Stmt) { + return ((!Stmt || !isa<CallExpr>(Stmt)) && + (RSCurr && + (RSCurr->isAllocated() || RSCurr->isAllocatedOfSizeZero())) && + (RSPrev && + !(RSPrev->isAllocated() || RSPrev->isAllocatedOfSizeZero()))); + } + + PathDiagnosticPieceRef VisitNode(const ExplodedNode *N, + BugReporterContext &BRC, + PathSensitiveBugReport &BR) override; + + PathDiagnosticPieceRef getEndPath(BugReporterContext &BRC, + const ExplodedNode *EndPathNode, + PathSensitiveBugReport &BR) override { + if (!IsLeak) + return nullptr; - PathDiagnosticLocation L = - PathDiagnosticLocation::createEndOfPath(EndPathNode, - BRC.getSourceManager()); - // Do not add the statement itself as a range in case of leak. - return std::make_shared<PathDiagnosticEventPiece>(L, BR.getDescription(), - false); - } + PathDiagnosticLocation L = BR.getLocation(); + // Do not add the statement itself as a range in case of leak. + return std::make_shared<PathDiagnosticEventPiece>(L, BR.getDescription(), + false); + } - private: - class StackHintGeneratorForReallocationFailed - : public StackHintGeneratorForSymbol { - public: - StackHintGeneratorForReallocationFailed(SymbolRef S, StringRef M) +private: + class StackHintGeneratorForReallocationFailed + : public StackHintGeneratorForSymbol { + public: + StackHintGeneratorForReallocationFailed(SymbolRef S, StringRef M) : StackHintGeneratorForSymbol(S, M) {} - std::string getMessageForArg(const Expr *ArgE, - unsigned ArgIndex) override { - // Printed parameters start at 1, not 0. - ++ArgIndex; + std::string getMessageForArg(const Expr *ArgE, unsigned ArgIndex) override { + // Printed parameters start at 1, not 0. + ++ArgIndex; - SmallString<200> buf; - llvm::raw_svector_ostream os(buf); + SmallString<200> buf; + llvm::raw_svector_ostream os(buf); - os << "Reallocation of " << ArgIndex << llvm::getOrdinalSuffix(ArgIndex) - << " parameter failed"; + os << "Reallocation of " << ArgIndex << llvm::getOrdinalSuffix(ArgIndex) + << " parameter failed"; - return os.str(); - } + return os.str(); + } - std::string getMessageForReturn(const CallExpr *CallExpr) override { - return "Reallocation of returned value failed"; - } - }; + std::string getMessageForReturn(const CallExpr *CallExpr) override { + return "Reallocation of returned value failed"; + } }; }; -} // end anonymous namespace -REGISTER_MAP_WITH_PROGRAMSTATE(RegionState, SymbolRef, RefState) -REGISTER_MAP_WITH_PROGRAMSTATE(ReallocPairs, SymbolRef, ReallocPair) -REGISTER_SET_WITH_PROGRAMSTATE(ReallocSizeZeroSymbols, SymbolRef) +} // end anonymous namespace // A map from the freed symbol to the symbol representing the return value of // the free function. @@ -591,7 +811,11 @@ public: }; } // end anonymous namespace -void MallocChecker::initIdentifierInfo(ASTContext &Ctx) const { +//===----------------------------------------------------------------------===// +// Methods of MemFunctionInfoTy. +//===----------------------------------------------------------------------===// + +void MemFunctionInfoTy::initIdentifierInfo(ASTContext &Ctx) const { if (II_malloc) return; II_alloca = &Ctx.Idents.get("alloca"); @@ -631,7 +855,8 @@ void MallocChecker::initIdentifierInfo(ASTContext &Ctx) const { II_g_try_realloc_n = &Ctx.Idents.get("g_try_realloc_n"); } -bool MallocChecker::isMemFunction(const FunctionDecl *FD, ASTContext &C) const { +bool MemFunctionInfoTy::isMemFunction(const FunctionDecl *FD, + ASTContext &C) const { if (isCMemFunction(FD, C, AF_Malloc, MemoryOperationKind::MOK_Any)) return true; @@ -647,10 +872,9 @@ bool MallocChecker::isMemFunction(const FunctionDecl *FD, ASTContext &C) const { return false; } -bool MallocChecker::isCMemFunction(const FunctionDecl *FD, - ASTContext &C, - AllocationFamily Family, - MemoryOperationKind MemKind) const { +bool MemFunctionInfoTy::isCMemFunction(const FunctionDecl *FD, ASTContext &C, + AllocationFamily Family, + MemoryOperationKind MemKind) const { if (!FD) return false; @@ -703,7 +927,7 @@ bool MallocChecker::isCMemFunction(const FunctionDecl *FD, if (Family != AF_Malloc) return false; - if (IsOptimistic && FD->hasAttrs()) { + if (ShouldIncludeOwnershipAnnotatedFunctions && FD->hasAttrs()) { for (const auto *I : FD->specific_attrs<OwnershipAttr>()) { OwnershipAttr::OwnershipKind OwnKind = I->getOwnKind(); if(OwnKind == OwnershipAttr::Takes || OwnKind == OwnershipAttr::Holds) { @@ -718,11 +942,8 @@ bool MallocChecker::isCMemFunction(const FunctionDecl *FD, return false; } - -// Tells if the callee is one of the builtin new/delete operators, including -// placement operators and other standard overloads. -bool MallocChecker::isStandardNewDelete(const FunctionDecl *FD, - ASTContext &C) const { +bool MemFunctionInfoTy::isStandardNewDelete(const FunctionDecl *FD, + ASTContext &C) const { if (!FD) return false; @@ -738,6 +959,10 @@ bool MallocChecker::isStandardNewDelete(const FunctionDecl *FD, return !L.isValid() || C.getSourceManager().isInSystemHeader(L); } +//===----------------------------------------------------------------------===// +// Methods of MallocChecker and MallocBugVisitor. +//===----------------------------------------------------------------------===// + llvm::Optional<ProgramStateRef> MallocChecker::performKernelMalloc( const CallExpr *CE, CheckerContext &C, const ProgramStateRef &State) const { // 3-argument malloc(), as commonly used in {Free,Net,Open}BSD Kernels: @@ -836,28 +1061,35 @@ void MallocChecker::checkPostStmt(const CallExpr *CE, CheckerContext &C) const { return; ProgramStateRef State = C.getState(); - bool ReleasedAllocatedMemory = false; + bool IsKnownToBeAllocatedMemory = false; if (FD->getKind() == Decl::Function) { - initIdentifierInfo(C.getASTContext()); + MemFunctionInfo.initIdentifierInfo(C.getASTContext()); IdentifierInfo *FunI = FD->getIdentifier(); - if (FunI == II_malloc || FunI == II_g_malloc || FunI == II_g_try_malloc) { - if (CE->getNumArgs() < 1) + if (FunI == MemFunctionInfo.II_malloc || + FunI == MemFunctionInfo.II_g_malloc || + FunI == MemFunctionInfo.II_g_try_malloc) { + switch (CE->getNumArgs()) { + default: return; - if (CE->getNumArgs() < 3) { + case 1: + State = MallocMemAux(C, CE, CE->getArg(0), UndefinedVal(), State); + State = ProcessZeroAllocCheck(C, CE, 0, State); + break; + case 2: State = MallocMemAux(C, CE, CE->getArg(0), UndefinedVal(), State); - if (CE->getNumArgs() == 1) - State = ProcessZeroAllocation(C, CE, 0, State); - } else if (CE->getNumArgs() == 3) { + break; + case 3: llvm::Optional<ProgramStateRef> MaybeState = performKernelMalloc(CE, C, State); if (MaybeState.hasValue()) State = MaybeState.getValue(); else State = MallocMemAux(C, CE, CE->getArg(0), UndefinedVal(), State); + break; } - } else if (FunI == II_kmalloc) { + } else if (FunI == MemFunctionInfo.II_kmalloc) { if (CE->getNumArgs() < 1) return; llvm::Optional<ProgramStateRef> MaybeState = @@ -866,100 +1098,116 @@ void MallocChecker::checkPostStmt(const CallExpr *CE, CheckerContext &C) const { State = MaybeState.getValue(); else State = MallocMemAux(C, CE, CE->getArg(0), UndefinedVal(), State); - } else if (FunI == II_valloc) { + } else if (FunI == MemFunctionInfo.II_valloc) { if (CE->getNumArgs() < 1) return; State = MallocMemAux(C, CE, CE->getArg(0), UndefinedVal(), State); - State = ProcessZeroAllocation(C, CE, 0, State); - } else if (FunI == II_realloc || FunI == II_g_realloc || - FunI == II_g_try_realloc) { - State = ReallocMemAux(C, CE, false, State); - State = ProcessZeroAllocation(C, CE, 1, State); - } else if (FunI == II_reallocf) { - State = ReallocMemAux(C, CE, true, State); - State = ProcessZeroAllocation(C, CE, 1, State); - } else if (FunI == II_calloc) { + State = ProcessZeroAllocCheck(C, CE, 0, State); + } else if (FunI == MemFunctionInfo.II_realloc || + FunI == MemFunctionInfo.II_g_realloc || + FunI == MemFunctionInfo.II_g_try_realloc) { + State = ReallocMemAux(C, CE, /*ShouldFreeOnFail*/ false, State); + State = ProcessZeroAllocCheck(C, CE, 1, State); + } else if (FunI == MemFunctionInfo.II_reallocf) { + State = ReallocMemAux(C, CE, /*ShouldFreeOnFail*/ true, State); + State = ProcessZeroAllocCheck(C, CE, 1, State); + } else if (FunI == MemFunctionInfo.II_calloc) { State = CallocMem(C, CE, State); - State = ProcessZeroAllocation(C, CE, 0, State); - State = ProcessZeroAllocation(C, CE, 1, State); - } else if (FunI == II_free || FunI == II_g_free || FunI == II_kfree) { + State = ProcessZeroAllocCheck(C, CE, 0, State); + State = ProcessZeroAllocCheck(C, CE, 1, State); + } else if (FunI == MemFunctionInfo.II_free || + FunI == MemFunctionInfo.II_g_free || + FunI == MemFunctionInfo.II_kfree) { if (suppressDeallocationsInSuspiciousContexts(CE, C)) return; - State = FreeMemAux(C, CE, State, 0, false, ReleasedAllocatedMemory); - } else if (FunI == II_strdup || FunI == II_win_strdup || - FunI == II_wcsdup || FunI == II_win_wcsdup) { + State = FreeMemAux(C, CE, State, 0, false, IsKnownToBeAllocatedMemory); + } else if (FunI == MemFunctionInfo.II_strdup || + FunI == MemFunctionInfo.II_win_strdup || + FunI == MemFunctionInfo.II_wcsdup || + FunI == MemFunctionInfo.II_win_wcsdup) { State = MallocUpdateRefState(C, CE, State); - } else if (FunI == II_strndup) { + } else if (FunI == MemFunctionInfo.II_strndup) { State = MallocUpdateRefState(C, CE, State); - } else if (FunI == II_alloca || FunI == II_win_alloca) { + } else if (FunI == MemFunctionInfo.II_alloca || + FunI == MemFunctionInfo.II_win_alloca) { if (CE->getNumArgs() < 1) return; State = MallocMemAux(C, CE, CE->getArg(0), UndefinedVal(), State, AF_Alloca); - State = ProcessZeroAllocation(C, CE, 0, State); - } else if (isStandardNewDelete(FD, C.getASTContext())) { + State = ProcessZeroAllocCheck(C, CE, 0, State); + } else if (MemFunctionInfo.isStandardNewDelete(FD, C.getASTContext())) { // Process direct calls to operator new/new[]/delete/delete[] functions // as distinct from new/new[]/delete/delete[] expressions that are // processed by the checkPostStmt callbacks for CXXNewExpr and // CXXDeleteExpr. - OverloadedOperatorKind K = FD->getOverloadedOperator(); - if (K == OO_New) { + switch (FD->getOverloadedOperator()) { + case OO_New: State = MallocMemAux(C, CE, CE->getArg(0), UndefinedVal(), State, AF_CXXNew); - State = ProcessZeroAllocation(C, CE, 0, State); - } - else if (K == OO_Array_New) { + State = ProcessZeroAllocCheck(C, CE, 0, State); + break; + case OO_Array_New: State = MallocMemAux(C, CE, CE->getArg(0), UndefinedVal(), State, AF_CXXNewArray); - State = ProcessZeroAllocation(C, CE, 0, State); - } - else if (K == OO_Delete || K == OO_Array_Delete) - State = FreeMemAux(C, CE, State, 0, false, ReleasedAllocatedMemory); - else + State = ProcessZeroAllocCheck(C, CE, 0, State); + break; + case OO_Delete: + case OO_Array_Delete: + State = FreeMemAux(C, CE, State, 0, false, IsKnownToBeAllocatedMemory); + break; + default: llvm_unreachable("not a new/delete operator"); - } else if (FunI == II_if_nameindex) { + } + } else if (FunI == MemFunctionInfo.II_if_nameindex) { // Should we model this differently? We can allocate a fixed number of // elements with zeros in the last one. State = MallocMemAux(C, CE, UnknownVal(), UnknownVal(), State, AF_IfNameIndex); - } else if (FunI == II_if_freenameindex) { - State = FreeMemAux(C, CE, State, 0, false, ReleasedAllocatedMemory); - } else if (FunI == II_g_malloc0 || FunI == II_g_try_malloc0) { + } else if (FunI == MemFunctionInfo.II_if_freenameindex) { + State = FreeMemAux(C, CE, State, 0, false, IsKnownToBeAllocatedMemory); + } else if (FunI == MemFunctionInfo.II_g_malloc0 || + FunI == MemFunctionInfo.II_g_try_malloc0) { if (CE->getNumArgs() < 1) return; SValBuilder &svalBuilder = C.getSValBuilder(); SVal zeroVal = svalBuilder.makeZeroVal(svalBuilder.getContext().CharTy); State = MallocMemAux(C, CE, CE->getArg(0), zeroVal, State); - State = ProcessZeroAllocation(C, CE, 0, State); - } else if (FunI == II_g_memdup) { + State = ProcessZeroAllocCheck(C, CE, 0, State); + } else if (FunI == MemFunctionInfo.II_g_memdup) { if (CE->getNumArgs() < 2) return; State = MallocMemAux(C, CE, CE->getArg(1), UndefinedVal(), State); - State = ProcessZeroAllocation(C, CE, 1, State); - } else if (FunI == II_g_malloc_n || FunI == II_g_try_malloc_n || - FunI == II_g_malloc0_n || FunI == II_g_try_malloc0_n) { + State = ProcessZeroAllocCheck(C, CE, 1, State); + } else if (FunI == MemFunctionInfo.II_g_malloc_n || + FunI == MemFunctionInfo.II_g_try_malloc_n || + FunI == MemFunctionInfo.II_g_malloc0_n || + FunI == MemFunctionInfo.II_g_try_malloc0_n) { if (CE->getNumArgs() < 2) return; SVal Init = UndefinedVal(); - if (FunI == II_g_malloc0_n || FunI == II_g_try_malloc0_n) { + if (FunI == MemFunctionInfo.II_g_malloc0_n || + FunI == MemFunctionInfo.II_g_try_malloc0_n) { SValBuilder &SB = C.getSValBuilder(); Init = SB.makeZeroVal(SB.getContext().CharTy); } SVal TotalSize = evalMulForBufferSize(C, CE->getArg(0), CE->getArg(1)); State = MallocMemAux(C, CE, TotalSize, Init, State); - State = ProcessZeroAllocation(C, CE, 0, State); - State = ProcessZeroAllocation(C, CE, 1, State); - } else if (FunI == II_g_realloc_n || FunI == II_g_try_realloc_n) { + State = ProcessZeroAllocCheck(C, CE, 0, State); + State = ProcessZeroAllocCheck(C, CE, 1, State); + } else if (FunI == MemFunctionInfo.II_g_realloc_n || + FunI == MemFunctionInfo.II_g_try_realloc_n) { if (CE->getNumArgs() < 3) return; - State = ReallocMemAux(C, CE, false, State, true); - State = ProcessZeroAllocation(C, CE, 1, State); - State = ProcessZeroAllocation(C, CE, 2, State); + State = ReallocMemAux(C, CE, /*ShouldFreeOnFail*/ false, State, + /*SuffixWithN*/ true); + State = ProcessZeroAllocCheck(C, CE, 1, State); + State = ProcessZeroAllocCheck(C, CE, 2, State); } } - if (IsOptimistic || ChecksEnabled[CK_MismatchedDeallocatorChecker]) { + if (MemFunctionInfo.ShouldIncludeOwnershipAnnotatedFunctions || + ChecksEnabled[CK_MismatchedDeallocatorChecker]) { // Check all the attributes, if there are any. // There can be multiple of these attributes. if (FD->hasAttrs()) @@ -979,9 +1227,9 @@ void MallocChecker::checkPostStmt(const CallExpr *CE, CheckerContext &C) const { } // Performs a 0-sized allocations check. -ProgramStateRef MallocChecker::ProcessZeroAllocation( - CheckerContext &C, const Expr *E, const unsigned AllocationSizeArg, - ProgramStateRef State, Optional<SVal> RetVal) const { +ProgramStateRef MallocChecker::ProcessZeroAllocCheck( + CheckerContext &C, const Expr *E, const unsigned IndexOfSizeArg, + ProgramStateRef State, Optional<SVal> RetVal) { if (!State) return nullptr; @@ -991,7 +1239,7 @@ ProgramStateRef MallocChecker::ProcessZeroAllocation( const Expr *Arg = nullptr; if (const CallExpr *CE = dyn_cast<CallExpr>(E)) { - Arg = CE->getArg(AllocationSizeArg); + Arg = CE->getArg(IndexOfSizeArg); } else if (const CXXNewExpr *NE = dyn_cast<CXXNewExpr>(E)) { if (NE->isArray()) @@ -1053,7 +1301,9 @@ static QualType getDeepPointeeType(QualType T) { return Result; } -static bool treatUnusedNewEscaped(const CXXNewExpr *NE) { +/// \returns true if the constructor invoked by \p NE has an argument of a +/// pointer/reference to a record type. +static bool hasNonTrivialConstructorCall(const CXXNewExpr *NE) { const CXXConstructExpr *ConstructE = NE->getConstructExpr(); if (!ConstructE) @@ -1083,11 +1333,17 @@ static bool treatUnusedNewEscaped(const CXXNewExpr *NE) { void MallocChecker::processNewAllocation(const CXXNewExpr *NE, CheckerContext &C, SVal Target) const { - if (!isStandardNewDelete(NE->getOperatorNew(), C.getASTContext())) + if (!MemFunctionInfo.isStandardNewDelete(NE->getOperatorNew(), + C.getASTContext())) return; - ParentMap &PM = C.getLocationContext()->getParentMap(); - if (!PM.isConsumedExpr(NE) && treatUnusedNewEscaped(NE)) + const ParentMap &PM = C.getLocationContext()->getParentMap(); + + // Non-trivial constructors have a chance to escape 'this', but marking all + // invocations of trivial constructors as escaped would cause too great of + // reduction of true positives, so let's just do that for constructors that + // have an argument of a pointer-to-record type. + if (!PM.isConsumedExpr(NE) && hasNonTrivialConstructorCall(NE)) return; ProgramStateRef State = C.getState(); @@ -1098,7 +1354,7 @@ void MallocChecker::processNewAllocation(const CXXNewExpr *NE, State = MallocUpdateRefState(C, NE, State, NE->isArray() ? AF_CXXNewArray : AF_CXXNew, Target); State = addExtentSize(C, NE, State, Target); - State = ProcessZeroAllocation(C, NE, 0, State, Target); + State = ProcessZeroAllocCheck(C, NE, 0, State, Target); C.addTransition(State); } @@ -1132,14 +1388,13 @@ ProgramStateRef MallocChecker::addExtentSize(CheckerContext &C, // Store the extent size for the (symbolic)region // containing the elements. Region = Target.getAsRegion() - ->getAs<SubRegion>() + ->castAs<SubRegion>() ->StripCasts() - ->getAs<SubRegion>(); + ->castAs<SubRegion>(); } else { ElementCount = svalBuilder.makeIntVal(1, true); - Region = Target.getAsRegion()->getAs<SubRegion>(); + Region = Target.getAsRegion()->castAs<SubRegion>(); } - assert(Region); // Set the region's extent equal to the Size in Bytes. QualType ElementType = NE->getAllocatedType(); @@ -1167,13 +1422,14 @@ void MallocChecker::checkPreStmt(const CXXDeleteExpr *DE, if (SymbolRef Sym = C.getSVal(DE->getArgument()).getAsSymbol()) checkUseAfterFree(Sym, C, DE->getArgument()); - if (!isStandardNewDelete(DE->getOperatorDelete(), C.getASTContext())) + if (!MemFunctionInfo.isStandardNewDelete(DE->getOperatorDelete(), + C.getASTContext())) return; ProgramStateRef State = C.getState(); - bool ReleasedAllocated; + bool IsKnownToBeAllocated; State = FreeMemAux(C, DE->getArgument(), DE, State, - /*Hold*/false, ReleasedAllocated); + /*Hold*/ false, IsKnownToBeAllocated); C.addTransition(State); } @@ -1213,11 +1469,11 @@ void MallocChecker::checkPostObjCMessage(const ObjCMethodCall &Call, if (!*FreeWhenDone) return; - bool ReleasedAllocatedMemory; - ProgramStateRef State = FreeMemAux(C, Call.getArgExpr(0), - Call.getOriginExpr(), C.getState(), - /*Hold=*/true, ReleasedAllocatedMemory, - /*ReturnsNullOnFailure=*/true); + bool IsKnownToBeAllocatedMemory; + ProgramStateRef State = + FreeMemAux(C, Call.getArgExpr(0), Call.getOriginExpr(), C.getState(), + /*Hold=*/true, IsKnownToBeAllocatedMemory, + /*RetNullOnFailure=*/true); C.addTransition(State); } @@ -1229,7 +1485,7 @@ MallocChecker::MallocMemReturnsAttr(CheckerContext &C, const CallExpr *CE, if (!State) return nullptr; - if (Att->getModule() != II_malloc) + if (Att->getModule() != MemFunctionInfo.II_malloc) return nullptr; OwnershipAttr::args_iterator I = Att->args_begin(), E = Att->args_end(); @@ -1295,11 +1551,10 @@ ProgramStateRef MallocChecker::MallocMemAux(CheckerContext &C, return MallocUpdateRefState(C, CE, State, Family); } -ProgramStateRef MallocChecker::MallocUpdateRefState(CheckerContext &C, - const Expr *E, - ProgramStateRef State, - AllocationFamily Family, - Optional<SVal> RetVal) { +static ProgramStateRef MallocUpdateRefState(CheckerContext &C, const Expr *E, + ProgramStateRef State, + AllocationFamily Family, + Optional<SVal> RetVal) { if (!State) return nullptr; @@ -1327,27 +1582,24 @@ ProgramStateRef MallocChecker::FreeMemAttr(CheckerContext &C, if (!State) return nullptr; - if (Att->getModule() != II_malloc) + if (Att->getModule() != MemFunctionInfo.II_malloc) return nullptr; - bool ReleasedAllocated = false; + bool IsKnownToBeAllocated = false; for (const auto &Arg : Att->args()) { ProgramStateRef StateI = FreeMemAux( C, CE, State, Arg.getASTIndex(), - Att->getOwnKind() == OwnershipAttr::Holds, ReleasedAllocated); + Att->getOwnKind() == OwnershipAttr::Holds, IsKnownToBeAllocated); if (StateI) State = StateI; } return State; } -ProgramStateRef MallocChecker::FreeMemAux(CheckerContext &C, - const CallExpr *CE, - ProgramStateRef State, - unsigned Num, - bool Hold, - bool &ReleasedAllocated, +ProgramStateRef MallocChecker::FreeMemAux(CheckerContext &C, const CallExpr *CE, + ProgramStateRef State, unsigned Num, + bool Hold, bool &IsKnownToBeAllocated, bool ReturnsNullOnFailure) const { if (!State) return nullptr; @@ -1355,8 +1607,8 @@ ProgramStateRef MallocChecker::FreeMemAux(CheckerContext &C, if (CE->getNumArgs() < (Num + 1)) return nullptr; - return FreeMemAux(C, CE->getArg(Num), CE, State, Hold, - ReleasedAllocated, ReturnsNullOnFailure); + return FreeMemAux(C, CE->getArg(Num), CE, State, Hold, IsKnownToBeAllocated, + ReturnsNullOnFailure); } /// Checks if the previous call to free on the given symbol failed - if free @@ -1374,8 +1626,10 @@ static bool didPreviousFreeFail(ProgramStateRef State, return false; } -AllocationFamily MallocChecker::getAllocationFamily(CheckerContext &C, - const Stmt *S) const { +static AllocationFamily +getAllocationFamily(const MemFunctionInfoTy &MemFunctionInfo, CheckerContext &C, + const Stmt *S) { + if (!S) return AF_None; @@ -1387,10 +1641,11 @@ AllocationFamily MallocChecker::getAllocationFamily(CheckerContext &C, ASTContext &Ctx = C.getASTContext(); - if (isCMemFunction(FD, Ctx, AF_Malloc, MemoryOperationKind::MOK_Any)) + if (MemFunctionInfo.isCMemFunction(FD, Ctx, AF_Malloc, + MemoryOperationKind::MOK_Any)) return AF_Malloc; - if (isStandardNewDelete(FD, Ctx)) { + if (MemFunctionInfo.isStandardNewDelete(FD, Ctx)) { OverloadedOperatorKind Kind = FD->getOverloadedOperator(); if (Kind == OO_New || Kind == OO_Delete) return AF_CXXNew; @@ -1398,10 +1653,12 @@ AllocationFamily MallocChecker::getAllocationFamily(CheckerContext &C, return AF_CXXNewArray; } - if (isCMemFunction(FD, Ctx, AF_IfNameIndex, MemoryOperationKind::MOK_Any)) + if (MemFunctionInfo.isCMemFunction(FD, Ctx, AF_IfNameIndex, + MemoryOperationKind::MOK_Any)) return AF_IfNameIndex; - if (isCMemFunction(FD, Ctx, AF_Alloca, MemoryOperationKind::MOK_Any)) + if (MemFunctionInfo.isCMemFunction(FD, Ctx, AF_Alloca, + MemoryOperationKind::MOK_Any)) return AF_Alloca; return AF_None; @@ -1419,8 +1676,8 @@ AllocationFamily MallocChecker::getAllocationFamily(CheckerContext &C, return AF_None; } -bool MallocChecker::printAllocDeallocName(raw_ostream &os, CheckerContext &C, - const Expr *E) const { +static bool printAllocDeallocName(raw_ostream &os, CheckerContext &C, + const Expr *E) { if (const CallExpr *CE = dyn_cast<CallExpr>(E)) { // FIXME: This doesn't handle indirect calls. const FunctionDecl *FD = CE->getDirectCallee(); @@ -1459,9 +1716,10 @@ bool MallocChecker::printAllocDeallocName(raw_ostream &os, CheckerContext &C, return false; } -void MallocChecker::printExpectedAllocName(raw_ostream &os, CheckerContext &C, - const Expr *E) const { - AllocationFamily Family = getAllocationFamily(C, E); +static void printExpectedAllocName(raw_ostream &os, + const MemFunctionInfoTy &MemFunctionInfo, + CheckerContext &C, const Expr *E) { + AllocationFamily Family = getAllocationFamily(MemFunctionInfo, C, E); switch(Family) { case AF_Malloc: os << "malloc()"; return; @@ -1474,8 +1732,7 @@ void MallocChecker::printExpectedAllocName(raw_ostream &os, CheckerContext &C, } } -void MallocChecker::printExpectedDeallocName(raw_ostream &os, - AllocationFamily Family) const { +static void printExpectedDeallocName(raw_ostream &os, AllocationFamily Family) { switch(Family) { case AF_Malloc: os << "free()"; return; case AF_CXXNew: os << "'delete'"; return; @@ -1490,9 +1747,8 @@ void MallocChecker::printExpectedDeallocName(raw_ostream &os, ProgramStateRef MallocChecker::FreeMemAux(CheckerContext &C, const Expr *ArgExpr, const Expr *ParentExpr, - ProgramStateRef State, - bool Hold, - bool &ReleasedAllocated, + ProgramStateRef State, bool Hold, + bool &IsKnownToBeAllocated, bool ReturnsNullOnFailure) const { if (!State) @@ -1566,6 +1822,9 @@ ProgramStateRef MallocChecker::FreeMemAux(CheckerContext &C, const RefState *RsBase = State->get<RegionState>(SymBase); SymbolRef PreviousRetStatusSymbol = nullptr; + IsKnownToBeAllocated = + RsBase && (RsBase->isAllocated() || RsBase->isAllocatedOfSizeZero()); + if (RsBase) { // Memory returned by alloca() shouldn't be freed. @@ -1588,7 +1847,8 @@ ProgramStateRef MallocChecker::FreeMemAux(CheckerContext &C, // Check if an expected deallocation function matches the real one. bool DeallocMatchesAlloc = - RsBase->getAllocationFamily() == getAllocationFamily(C, ParentExpr); + RsBase->getAllocationFamily() == + getAllocationFamily(MemFunctionInfo, C, ParentExpr); if (!DeallocMatchesAlloc) { ReportMismatchedDealloc(C, ArgExpr->getSourceRange(), ParentExpr, RsBase, SymBase, Hold); @@ -1614,9 +1874,6 @@ ProgramStateRef MallocChecker::FreeMemAux(CheckerContext &C, return nullptr; } - ReleasedAllocated = (RsBase != nullptr) && (RsBase->isAllocated() || - RsBase->isAllocatedOfSizeZero()); - // Clean out the info on previous call to free return info. State = State->remove<FreeReturnValue>(SymBase); @@ -1631,8 +1888,9 @@ ProgramStateRef MallocChecker::FreeMemAux(CheckerContext &C, } } - AllocationFamily Family = RsBase ? RsBase->getAllocationFamily() - : getAllocationFamily(C, ParentExpr); + AllocationFamily Family = + RsBase ? RsBase->getAllocationFamily() + : getAllocationFamily(MemFunctionInfo, C, ParentExpr); // Normal free. if (Hold) return State->set<RegionState>(SymBase, @@ -1682,8 +1940,8 @@ Optional<MallocChecker::CheckKind> MallocChecker::getCheckIfTracked(CheckerContext &C, const Stmt *AllocDeallocStmt, bool IsALeakCheck) const { - return getCheckIfTracked(getAllocationFamily(C, AllocDeallocStmt), - IsALeakCheck); + return getCheckIfTracked( + getAllocationFamily(MemFunctionInfo, C, AllocDeallocStmt), IsALeakCheck); } Optional<MallocChecker::CheckKind> @@ -1821,9 +2079,10 @@ void MallocChecker::ReportBadFree(CheckerContext &C, SVal ArgVal, else os << "not memory allocated by "; - printExpectedAllocName(os, C, DeallocExpr); + printExpectedAllocName(os, MemFunctionInfo, C, DeallocExpr); - auto R = llvm::make_unique<BugReport>(*BT_BadFree[*CheckKind], os.str(), N); + auto R = std::make_unique<PathSensitiveBugReport>(*BT_BadFree[*CheckKind], + os.str(), N); R->markInteresting(MR); R->addRange(Range); C.emitReport(std::move(R)); @@ -1847,7 +2106,7 @@ void MallocChecker::ReportFreeAlloca(CheckerContext &C, SVal ArgVal, BT_FreeAlloca[*CheckKind].reset(new BugType( CheckNames[*CheckKind], "Free alloca()", categories::MemoryError)); - auto R = llvm::make_unique<BugReport>( + auto R = std::make_unique<PathSensitiveBugReport>( *BT_FreeAlloca[*CheckKind], "Memory allocated by alloca() should not be deallocated", N); R->markInteresting(ArgVal.getAsRegion()); @@ -1903,10 +2162,11 @@ void MallocChecker::ReportMismatchedDealloc(CheckerContext &C, os << ", not " << DeallocOs.str(); } - auto R = llvm::make_unique<BugReport>(*BT_MismatchedDealloc, os.str(), N); + auto R = std::make_unique<PathSensitiveBugReport>(*BT_MismatchedDealloc, + os.str(), N); R->markInteresting(Sym); R->addRange(Range); - R->addVisitor(llvm::make_unique<MallocBugVisitor>(Sym)); + R->addVisitor(std::make_unique<MallocBugVisitor>(Sym)); C.emitReport(std::move(R)); } } @@ -1962,7 +2222,8 @@ void MallocChecker::ReportOffsetFree(CheckerContext &C, SVal ArgVal, else os << "allocated memory"; - auto R = llvm::make_unique<BugReport>(*BT_OffsetFree[*CheckKind], os.str(), N); + auto R = std::make_unique<PathSensitiveBugReport>(*BT_OffsetFree[*CheckKind], + os.str(), N); R->markInteresting(MR->getBaseRegion()); R->addRange(Range); C.emitReport(std::move(R)); @@ -1988,15 +2249,16 @@ void MallocChecker::ReportUseAfterFree(CheckerContext &C, SourceRange Range, AllocationFamily AF = C.getState()->get<RegionState>(Sym)->getAllocationFamily(); - auto R = llvm::make_unique<BugReport>(*BT_UseFree[*CheckKind], + auto R = std::make_unique<PathSensitiveBugReport>( + *BT_UseFree[*CheckKind], AF == AF_InnerBuffer - ? "Inner pointer of container used after re/deallocation" - : "Use of memory after it is freed", + ? "Inner pointer of container used after re/deallocation" + : "Use of memory after it is freed", N); R->markInteresting(Sym); R->addRange(Range); - R->addVisitor(llvm::make_unique<MallocBugVisitor>(Sym)); + R->addVisitor(std::make_unique<MallocBugVisitor>(Sym)); if (AF == AF_InnerBuffer) R->addVisitor(allocation_state::getInnerPointerBRVisitor(Sym)); @@ -2022,7 +2284,7 @@ void MallocChecker::ReportDoubleFree(CheckerContext &C, SourceRange Range, BT_DoubleFree[*CheckKind].reset(new BugType( CheckNames[*CheckKind], "Double free", categories::MemoryError)); - auto R = llvm::make_unique<BugReport>( + auto R = std::make_unique<PathSensitiveBugReport>( *BT_DoubleFree[*CheckKind], (Released ? "Attempt to free released memory" : "Attempt to free non-owned memory"), @@ -2031,7 +2293,7 @@ void MallocChecker::ReportDoubleFree(CheckerContext &C, SourceRange Range, R->markInteresting(Sym); if (PrevSym) R->markInteresting(PrevSym); - R->addVisitor(llvm::make_unique<MallocBugVisitor>(Sym)); + R->addVisitor(std::make_unique<MallocBugVisitor>(Sym)); C.emitReport(std::move(R)); } } @@ -2051,11 +2313,11 @@ void MallocChecker::ReportDoubleDelete(CheckerContext &C, SymbolRef Sym) const { "Double delete", categories::MemoryError)); - auto R = llvm::make_unique<BugReport>( + auto R = std::make_unique<PathSensitiveBugReport>( *BT_DoubleDelete, "Attempt to delete released memory", N); R->markInteresting(Sym); - R->addVisitor(llvm::make_unique<MallocBugVisitor>(Sym)); + R->addVisitor(std::make_unique<MallocBugVisitor>(Sym)); C.emitReport(std::move(R)); } } @@ -2079,13 +2341,13 @@ void MallocChecker::ReportUseZeroAllocated(CheckerContext &C, new BugType(CheckNames[*CheckKind], "Use of zero allocated", categories::MemoryError)); - auto R = llvm::make_unique<BugReport>(*BT_UseZerroAllocated[*CheckKind], - "Use of zero-allocated memory", N); + auto R = std::make_unique<PathSensitiveBugReport>( + *BT_UseZerroAllocated[*CheckKind], "Use of zero-allocated memory", N); R->addRange(Range); if (Sym) { R->markInteresting(Sym); - R->addVisitor(llvm::make_unique<MallocBugVisitor>(Sym)); + R->addVisitor(std::make_unique<MallocBugVisitor>(Sym)); } C.emitReport(std::move(R)); } @@ -2119,7 +2381,8 @@ void MallocChecker::ReportFunctionPointerFree(CheckerContext &C, SVal ArgVal, Os << " is a function pointer"; - auto R = llvm::make_unique<BugReport>(*BT_BadFree[*CheckKind], Os.str(), N); + auto R = std::make_unique<PathSensitiveBugReport>(*BT_BadFree[*CheckKind], + Os.str(), N); R->markInteresting(MR); R->addRange(Range); C.emitReport(std::move(R)); @@ -2128,7 +2391,7 @@ void MallocChecker::ReportFunctionPointerFree(CheckerContext &C, SVal ArgVal, ProgramStateRef MallocChecker::ReallocMemAux(CheckerContext &C, const CallExpr *CE, - bool FreesOnFail, + bool ShouldFreeOnFail, ProgramStateRef State, bool SuffixWithN) const { if (!State) @@ -2193,33 +2456,32 @@ ProgramStateRef MallocChecker::ReallocMemAux(CheckerContext &C, if (!FromPtr || !ToPtr) return nullptr; - bool ReleasedAllocated = false; + bool IsKnownToBeAllocated = false; // If the size is 0, free the memory. if (SizeIsZero) - if (ProgramStateRef stateFree = FreeMemAux(C, CE, StateSizeIsZero, 0, - false, ReleasedAllocated)){ - // The semantics of the return value are: - // If size was equal to 0, either NULL or a pointer suitable to be passed - // to free() is returned. We just free the input pointer and do not add - // any constrains on the output pointer. + // The semantics of the return value are: + // If size was equal to 0, either NULL or a pointer suitable to be passed + // to free() is returned. We just free the input pointer and do not add + // any constrains on the output pointer. + if (ProgramStateRef stateFree = + FreeMemAux(C, CE, StateSizeIsZero, 0, false, IsKnownToBeAllocated)) return stateFree; - } // Default behavior. if (ProgramStateRef stateFree = - FreeMemAux(C, CE, State, 0, false, ReleasedAllocated)) { + FreeMemAux(C, CE, State, 0, false, IsKnownToBeAllocated)) { ProgramStateRef stateRealloc = MallocMemAux(C, CE, TotalSize, UnknownVal(), stateFree); if (!stateRealloc) return nullptr; - ReallocPairKind Kind = RPToBeFreedAfterFailure; - if (FreesOnFail) - Kind = RPIsFreeOnFailure; - else if (!ReleasedAllocated) - Kind = RPDoNotTrackAfterFailure; + OwnershipAfterReallocKind Kind = OAR_ToBeFreedAfterFailure; + if (ShouldFreeOnFail) + Kind = OAR_FreeOnFailure; + else if (!IsKnownToBeAllocated) + Kind = OAR_DoNotTrackAfterFailure; // Record the info about the reallocated symbol so that we could properly // process failed reallocation. @@ -2247,9 +2509,9 @@ ProgramStateRef MallocChecker::CallocMem(CheckerContext &C, const CallExpr *CE, return MallocMemAux(C, CE, TotalSize, zeroVal, State); } -LeakInfo -MallocChecker::getAllocationSite(const ExplodedNode *N, SymbolRef Sym, - CheckerContext &C) const { +MallocChecker::LeakInfo MallocChecker::getAllocationSite(const ExplodedNode *N, + SymbolRef Sym, + CheckerContext &C) { const LocationContext *LeakContext = N->getLocationContext(); // Walk the ExplodedGraph backwards and find the first node that referred to // the tracked symbol. @@ -2329,7 +2591,7 @@ void MallocChecker::reportLeak(SymbolRef Sym, ExplodedNode *N, const MemRegion *Region = nullptr; std::tie(AllocNode, Region) = getAllocationSite(N, Sym, C); - const Stmt *AllocationStmt = PathDiagnosticLocation::getStmt(AllocNode); + const Stmt *AllocationStmt = AllocNode->getStmtForDiagnostics(); if (AllocationStmt) LocUsedForUniqueing = PathDiagnosticLocation::createBegin(AllocationStmt, C.getSourceManager(), @@ -2344,11 +2606,11 @@ void MallocChecker::reportLeak(SymbolRef Sym, ExplodedNode *N, os << "Potential memory leak"; } - auto R = llvm::make_unique<BugReport>( + auto R = std::make_unique<PathSensitiveBugReport>( *BT_Leak[*CheckKind], os.str(), N, LocUsedForUniqueing, AllocNode->getLocationContext()->getDecl()); R->markInteresting(Sym); - R->addVisitor(llvm::make_unique<MallocBugVisitor>(Sym, true)); + R->addVisitor(std::make_unique<MallocBugVisitor>(Sym, true)); C.emitReport(std::move(R)); } @@ -2430,9 +2692,10 @@ void MallocChecker::checkPreCall(const CallEvent &Call, ASTContext &Ctx = C.getASTContext(); if (ChecksEnabled[CK_MallocChecker] && - (isCMemFunction(FD, Ctx, AF_Malloc, MemoryOperationKind::MOK_Free) || - isCMemFunction(FD, Ctx, AF_IfNameIndex, - MemoryOperationKind::MOK_Free))) + (MemFunctionInfo.isCMemFunction(FD, Ctx, AF_Malloc, + MemoryOperationKind::MOK_Free) || + MemFunctionInfo.isCMemFunction(FD, Ctx, AF_IfNameIndex, + MemoryOperationKind::MOK_Free))) return; } @@ -2535,7 +2798,7 @@ void MallocChecker::checkPostStmt(const BlockExpr *BE, C.addTransition(state); } -bool MallocChecker::isReleased(SymbolRef Sym, CheckerContext &C) const { +static bool isReleased(SymbolRef Sym, CheckerContext &C) { assert(Sym); const RefState *RS = C.getState()->get<RegionState>(Sym); return (RS && RS->isReleased()); @@ -2640,13 +2903,17 @@ ProgramStateRef MallocChecker::evalAssume(ProgramStateRef state, SymbolRef ReallocSym = I.getData().ReallocatedSym; if (const RefState *RS = state->get<RegionState>(ReallocSym)) { if (RS->isReleased()) { - if (I.getData().Kind == RPToBeFreedAfterFailure) + switch (I.getData().Kind) { + case OAR_ToBeFreedAfterFailure: state = state->set<RegionState>(ReallocSym, RefState::getAllocated(RS->getAllocationFamily(), RS->getStmt())); - else if (I.getData().Kind == RPDoNotTrackAfterFailure) + break; + case OAR_DoNotTrackAfterFailure: state = state->remove<RegionState>(ReallocSym); - else - assert(I.getData().Kind == RPIsFreeOnFailure); + break; + default: + assert(I.getData().Kind == OAR_FreeOnFailure); + } } } state = state->remove<ReallocPairs>(I.getKey()); @@ -2729,7 +2996,7 @@ bool MallocChecker::mayFreeAnyEscapedMemoryOrIsModeledExplicitly( // If it's one of the allocation functions we can reason about, we model // its behavior explicitly. - if (isMemFunction(FD, ASTC)) + if (MemFunctionInfo.isMemFunction(FD, ASTC)) return false; // If it's not a system call, assume it frees memory. @@ -2821,35 +3088,32 @@ bool MallocChecker::mayFreeAnyEscapedMemoryOrIsModeledExplicitly( return false; } -static bool retTrue(const RefState *RS) { - return true; -} - -static bool checkIfNewOrNewArrayFamily(const RefState *RS) { - return (RS->getAllocationFamily() == AF_CXXNewArray || - RS->getAllocationFamily() == AF_CXXNew); -} - ProgramStateRef MallocChecker::checkPointerEscape(ProgramStateRef State, const InvalidatedSymbols &Escaped, const CallEvent *Call, PointerEscapeKind Kind) const { - return checkPointerEscapeAux(State, Escaped, Call, Kind, &retTrue); + return checkPointerEscapeAux(State, Escaped, Call, Kind, + /*IsConstPointerEscape*/ false); } ProgramStateRef MallocChecker::checkConstPointerEscape(ProgramStateRef State, const InvalidatedSymbols &Escaped, const CallEvent *Call, PointerEscapeKind Kind) const { + // If a const pointer escapes, it may not be freed(), but it could be deleted. return checkPointerEscapeAux(State, Escaped, Call, Kind, - &checkIfNewOrNewArrayFamily); + /*IsConstPointerEscape*/ true); } -ProgramStateRef MallocChecker::checkPointerEscapeAux(ProgramStateRef State, - const InvalidatedSymbols &Escaped, - const CallEvent *Call, - PointerEscapeKind Kind, - bool(*CheckRefState)(const RefState*)) const { +static bool checkIfNewOrNewArrayFamily(const RefState *RS) { + return (RS->getAllocationFamily() == AF_CXXNewArray || + RS->getAllocationFamily() == AF_CXXNew); +} + +ProgramStateRef MallocChecker::checkPointerEscapeAux( + ProgramStateRef State, const InvalidatedSymbols &Escaped, + const CallEvent *Call, PointerEscapeKind Kind, + bool IsConstPointerEscape) const { // If we know that the call does not free memory, or we want to process the // call later, keep tracking the top level arguments. SymbolRef EscapingSymbol = nullptr; @@ -2868,12 +3132,10 @@ ProgramStateRef MallocChecker::checkPointerEscapeAux(ProgramStateRef State, if (EscapingSymbol && EscapingSymbol != sym) continue; - if (const RefState *RS = State->get<RegionState>(sym)) { - if ((RS->isAllocated() || RS->isAllocatedOfSizeZero()) && - CheckRefState(RS)) { - State = State->set<RegionState>(sym, RefState::getEscaped(RS)); - } - } + if (const RefState *RS = State->get<RegionState>(sym)) + if (RS->isAllocated() || RS->isAllocatedOfSizeZero()) + if (!IsConstPointerEscape || checkIfNewOrNewArrayFamily(RS)) + State = State->set<RegionState>(sym, RefState::getEscaped(RS)); } return State; } @@ -2883,9 +3145,8 @@ static SymbolRef findFailedReallocSymbol(ProgramStateRef currState, ReallocPairsTy currMap = currState->get<ReallocPairs>(); ReallocPairsTy prevMap = prevState->get<ReallocPairs>(); - for (ReallocPairsTy::iterator I = prevMap.begin(), E = prevMap.end(); - I != E; ++I) { - SymbolRef sym = I.getKey(); + for (const ReallocPairsTy::value_type &Pair : prevMap) { + SymbolRef sym = Pair.first; if (!currMap.lookup(sym)) return sym; } @@ -2906,19 +3167,19 @@ static bool isReferenceCountingPointerDestructor(const CXXDestructorDecl *DD) { return false; } -std::shared_ptr<PathDiagnosticPiece> MallocChecker::MallocBugVisitor::VisitNode( - const ExplodedNode *N, BugReporterContext &BRC, BugReport &BR) { - +PathDiagnosticPieceRef MallocBugVisitor::VisitNode(const ExplodedNode *N, + BugReporterContext &BRC, + PathSensitiveBugReport &BR) { ProgramStateRef state = N->getState(); ProgramStateRef statePrev = N->getFirstPred()->getState(); - const RefState *RS = state->get<RegionState>(Sym); + const RefState *RSCurr = state->get<RegionState>(Sym); const RefState *RSPrev = statePrev->get<RegionState>(Sym); - const Stmt *S = PathDiagnosticLocation::getStmt(N); + const Stmt *S = N->getStmtForDiagnostics(); // When dealing with containers, we sometimes want to give a note // even if the statement is missing. - if (!S && (!RS || RS->getAllocationFamily() != AF_InnerBuffer)) + if (!S && (!RSCurr || RSCurr->getAllocationFamily() != AF_InnerBuffer)) return nullptr; const LocationContext *CurrentLC = N->getLocationContext(); @@ -2948,17 +3209,17 @@ std::shared_ptr<PathDiagnosticPiece> MallocChecker::MallocBugVisitor::VisitNode( // Find out if this is an interesting point and what is the kind. StringRef Msg; - StackHintGeneratorForSymbol *StackHint = nullptr; + std::unique_ptr<StackHintGeneratorForSymbol> StackHint = nullptr; SmallString<256> Buf; llvm::raw_svector_ostream OS(Buf); if (Mode == Normal) { - if (isAllocated(RS, RSPrev, S)) { + if (isAllocated(RSCurr, RSPrev, S)) { Msg = "Memory is allocated"; - StackHint = new StackHintGeneratorForSymbol(Sym, - "Returned allocated memory"); - } else if (isReleased(RS, RSPrev, S)) { - const auto Family = RS->getAllocationFamily(); + StackHint = std::make_unique<StackHintGeneratorForSymbol>( + Sym, "Returned allocated memory"); + } else if (isReleased(RSCurr, RSPrev, S)) { + const auto Family = RSCurr->getAllocationFamily(); switch (Family) { case AF_Alloca: case AF_Malloc: @@ -2966,8 +3227,8 @@ std::shared_ptr<PathDiagnosticPiece> MallocChecker::MallocBugVisitor::VisitNode( case AF_CXXNewArray: case AF_IfNameIndex: Msg = "Memory is released"; - StackHint = new StackHintGeneratorForSymbol(Sym, - "Returning; memory was released"); + StackHint = std::make_unique<StackHintGeneratorForSymbol>( + Sym, "Returning; memory was released"); break; case AF_InnerBuffer: { const MemRegion *ObjRegion = @@ -2978,11 +3239,11 @@ std::shared_ptr<PathDiagnosticPiece> MallocChecker::MallocBugVisitor::VisitNode( if (N->getLocation().getKind() == ProgramPoint::PostImplicitCallKind) { OS << "deallocated by call to destructor"; - StackHint = new StackHintGeneratorForSymbol(Sym, - "Returning; inner buffer was deallocated"); + StackHint = std::make_unique<StackHintGeneratorForSymbol>( + Sym, "Returning; inner buffer was deallocated"); } else { OS << "reallocated by call to '"; - const Stmt *S = RS->getStmt(); + const Stmt *S = RSCurr->getStmt(); if (const auto *MemCallE = dyn_cast<CXXMemberCallExpr>(S)) { OS << MemCallE->getMethodDecl()->getNameAsString(); } else if (const auto *OpCallE = dyn_cast<CXXOperatorCallExpr>(S)) { @@ -2994,8 +3255,8 @@ std::shared_ptr<PathDiagnosticPiece> MallocChecker::MallocBugVisitor::VisitNode( OS << (D ? D->getNameAsString() : "unknown"); } OS << "'"; - StackHint = new StackHintGeneratorForSymbol(Sym, - "Returning; inner buffer was reallocated"); + StackHint = std::make_unique<StackHintGeneratorForSymbol>( + Sym, "Returning; inner buffer was reallocated"); } Msg = OS.str(); break; @@ -3033,14 +3294,14 @@ std::shared_ptr<PathDiagnosticPiece> MallocChecker::MallocBugVisitor::VisitNode( } } } - } else if (isRelinquished(RS, RSPrev, S)) { + } else if (isRelinquished(RSCurr, RSPrev, S)) { Msg = "Memory ownership is transferred"; - StackHint = new StackHintGeneratorForSymbol(Sym, ""); - } else if (isReallocFailedCheck(RS, RSPrev, S)) { + StackHint = std::make_unique<StackHintGeneratorForSymbol>(Sym, ""); + } else if (hasReallocFailed(RSCurr, RSPrev, S)) { Mode = ReallocationFailed; Msg = "Reallocation failed"; - StackHint = new StackHintGeneratorForReallocationFailed(Sym, - "Reallocation failed"); + StackHint = std::make_unique<StackHintGeneratorForReallocationFailed>( + Sym, "Reallocation failed"); if (SymbolRef sym = findFailedReallocSymbol(state, statePrev)) { // Is it possible to fail two reallocs WITHOUT testing in between? @@ -3059,21 +3320,24 @@ std::shared_ptr<PathDiagnosticPiece> MallocChecker::MallocBugVisitor::VisitNode( if (!statePrev->get<RegionState>(FailedReallocSymbol)) { // We're at the reallocation point. Msg = "Attempt to reallocate memory"; - StackHint = new StackHintGeneratorForSymbol(Sym, - "Returned reallocated memory"); + StackHint = std::make_unique<StackHintGeneratorForSymbol>( + Sym, "Returned reallocated memory"); FailedReallocSymbol = nullptr; Mode = Normal; } } - if (Msg.empty()) + if (Msg.empty()) { + assert(!StackHint); return nullptr; + } + assert(StackHint); // Generate the extra diagnostic. PathDiagnosticLocation Pos; if (!S) { - assert(RS->getAllocationFamily() == AF_InnerBuffer); + assert(RSCurr->getAllocationFamily() == AF_InnerBuffer); auto PostImplCall = N->getLocation().getAs<PostImplicitCall>(); if (!PostImplCall) return nullptr; @@ -3084,7 +3348,9 @@ std::shared_ptr<PathDiagnosticPiece> MallocChecker::MallocBugVisitor::VisitNode( N->getLocationContext()); } - return std::make_shared<PathDiagnosticEventPiece>(Pos, Msg, true, StackHint); + auto P = std::make_shared<PathDiagnosticEventPiece>(Pos, Msg, true); + BR.addCallStackHint(P, std::move(StackHint)); + return P; } void MallocChecker::printState(raw_ostream &Out, ProgramStateRef State, @@ -3131,13 +3397,13 @@ void ento::registerInnerPointerCheckerAux(CheckerManager &mgr) { MallocChecker *checker = mgr.getChecker<MallocChecker>(); checker->ChecksEnabled[MallocChecker::CK_InnerPointerChecker] = true; checker->CheckNames[MallocChecker::CK_InnerPointerChecker] = - mgr.getCurrentCheckName(); + mgr.getCurrentCheckerName(); } void ento::registerDynamicMemoryModeling(CheckerManager &mgr) { auto *checker = mgr.registerChecker<MallocChecker>(); - checker->IsOptimistic = mgr.getAnalyzerOptions().getCheckerBooleanOption( - checker, "Optimistic"); + checker->MemFunctionInfo.ShouldIncludeOwnershipAnnotatedFunctions = + mgr.getAnalyzerOptions().getCheckerBooleanOption(checker, "Optimistic"); } bool ento::shouldRegisterDynamicMemoryModeling(const LangOptions &LO) { @@ -3148,12 +3414,11 @@ bool ento::shouldRegisterDynamicMemoryModeling(const LangOptions &LO) { void ento::register##name(CheckerManager &mgr) { \ MallocChecker *checker = mgr.getChecker<MallocChecker>(); \ checker->ChecksEnabled[MallocChecker::CK_##name] = true; \ - checker->CheckNames[MallocChecker::CK_##name] = mgr.getCurrentCheckName(); \ + checker->CheckNames[MallocChecker::CK_##name] = \ + mgr.getCurrentCheckerName(); \ } \ \ - bool ento::shouldRegister##name(const LangOptions &LO) { \ - return true; \ - } + bool ento::shouldRegister##name(const LangOptions &LO) { return true; } REGISTER_CHECKER(MallocChecker) REGISTER_CHECKER(NewDeleteChecker) |