|
52 | 52 | #include "clang/AST/DeclTemplate.h"
|
53 | 53 | #include "clang/AST/Expr.h"
|
54 | 54 | #include "clang/AST/ExprCXX.h"
|
| 55 | +#include "clang/AST/Type.h" |
| 56 | +#include "clang/AST/TemplateBase.h" |
| 57 | + |
| 58 | + |
55 | 59 | #include "clang/AST/ParentMap.h"
|
56 | 60 | #include "clang/ASTMatchers/ASTMatchFinder.h"
|
57 | 61 | #include "clang/ASTMatchers/ASTMatchers.h"
|
|
78 | 82 | #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
|
79 | 83 | #include "clang/StaticAnalyzer/Core/PathSensitive/SymbolManager.h"
|
80 | 84 | #include "llvm/ADT/STLExtras.h"
|
| 85 | +#include "llvm/ADT/SmallVector.h" |
81 | 86 | #include "llvm/ADT/StringExtras.h"
|
82 | 87 | #include "llvm/Support/Casting.h"
|
83 | 88 | #include "llvm/Support/Compiler.h"
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@@ -1096,6 +1101,23 @@ class StopTrackingCallback final : public SymbolVisitor {
|
1096 | 1101 | return true;
|
1097 | 1102 | }
|
1098 | 1103 | };
|
| 1104 | + |
| 1105 | +class EscapeTrackedCallback final : public SymbolVisitor { |
| 1106 | + ProgramStateRef State; |
| 1107 | + |
| 1108 | +public: |
| 1109 | + explicit EscapeTrackedCallback(ProgramStateRef S) : State(std::move(S)) {} |
| 1110 | + ProgramStateRef getState() const { return State; } |
| 1111 | + |
| 1112 | + bool VisitSymbol(SymbolRef Sym) override { |
| 1113 | + if (const RefState *RS = State->get<RegionState>(Sym)) { |
| 1114 | + if (RS->isAllocated() || RS->isAllocatedOfSizeZero()) { |
| 1115 | + State = State->set<RegionState>(Sym, RefState::getEscaped(RS)); |
| 1116 | + } |
| 1117 | + } |
| 1118 | + return true; |
| 1119 | + } |
| 1120 | +}; |
1099 | 1121 | } // end anonymous namespace
|
1100 | 1122 |
|
1101 | 1123 | static bool isStandardNew(const FunctionDecl *FD) {
|
@@ -3068,11 +3090,197 @@ void MallocChecker::checkDeadSymbols(SymbolReaper &SymReaper,
|
3068 | 3090 | C.addTransition(state->set<RegionState>(RS), N);
|
3069 | 3091 | }
|
3070 | 3092 |
|
| 3093 | +static QualType canonicalStrip(QualType QT) { |
| 3094 | + return QT.getCanonicalType().getUnqualifiedType(); |
| 3095 | +} |
| 3096 | + |
| 3097 | +static bool isInStdNamespace(const DeclContext *DC) { |
| 3098 | + while (DC) { |
| 3099 | + if (const auto *NS = dyn_cast<NamespaceDecl>(DC)) |
| 3100 | + if (NS->isStdNamespace()) |
| 3101 | + return true; |
| 3102 | + DC = DC->getParent(); |
| 3103 | + } |
| 3104 | + return false; |
| 3105 | +} |
| 3106 | + |
| 3107 | +static bool isUniquePtrType(QualType QT) { |
| 3108 | + QT = canonicalStrip(QT); |
| 3109 | + |
| 3110 | + // First try TemplateSpecializationType (for std::unique_ptr) |
| 3111 | + const auto *TST = QT->getAs<TemplateSpecializationType>(); |
| 3112 | + if (TST) { |
| 3113 | + const TemplateDecl *TD = TST->getTemplateName().getAsTemplateDecl(); |
| 3114 | + if (!TD) return false; |
| 3115 | + |
| 3116 | + const auto *ND = dyn_cast_or_null<NamedDecl>(TD->getTemplatedDecl()); |
| 3117 | + if (!ND) return false; |
| 3118 | + |
| 3119 | + if (ND->getName() != "unique_ptr") return false; |
| 3120 | + |
| 3121 | + // Check if it's in std namespace |
| 3122 | + const DeclContext *DC = ND->getDeclContext(); |
| 3123 | + if (isInStdNamespace(DC)) return true; |
| 3124 | + } |
| 3125 | + |
| 3126 | + // Also try RecordType (for custom unique_ptr) |
| 3127 | + const auto *RT = QT->getAs<RecordType>(); |
| 3128 | + if (RT) { |
| 3129 | + const auto *RD = RT->getDecl(); |
| 3130 | + if (RD && RD->getName() == "unique_ptr") { |
| 3131 | + // Accept any custom unique_ptr implementation |
| 3132 | + return true; |
| 3133 | + } |
| 3134 | + } |
| 3135 | + |
| 3136 | + return false; |
| 3137 | +} |
| 3138 | + |
| 3139 | +static void collectDirectUniquePtrFieldRegions(const MemRegion *Base, |
| 3140 | + QualType RecQT, |
| 3141 | + ProgramStateRef State, |
| 3142 | + SmallVectorImpl<const MemRegion*> &Out) { |
| 3143 | + if (!Base) return; |
| 3144 | + const auto *CRD = RecQT->getAsCXXRecordDecl(); |
| 3145 | + if (!CRD) return; |
| 3146 | + |
| 3147 | + for (const FieldDecl *FD : CRD->fields()) { |
| 3148 | + if (!isUniquePtrType(FD->getType())) |
| 3149 | + continue; |
| 3150 | + SVal L = State->getLValue(FD, loc::MemRegionVal(Base)); |
| 3151 | + if (const MemRegion *FR = L.getAsRegion()) |
| 3152 | + Out.push_back(FR); |
| 3153 | + } |
| 3154 | +} |
| 3155 | + |
3071 | 3156 | void MallocChecker::checkPostCall(const CallEvent &Call,
|
3072 | 3157 | CheckerContext &C) const {
|
| 3158 | + // Keep existing post-call handlers. |
3073 | 3159 | if (const auto *PostFN = PostFnMap.lookup(Call)) {
|
3074 | 3160 | (*PostFN)(this, C.getState(), Call, C);
|
3075 |
| - return; |
| 3161 | + } |
| 3162 | + |
| 3163 | + SmallVector<const MemRegion*, 8> UniquePtrFieldRoots; |
| 3164 | + |
| 3165 | + |
| 3166 | + |
| 3167 | + for (unsigned I = 0, E = Call.getNumArgs(); I != E; ++I) { |
| 3168 | + const Expr *AE = Call.getArgExpr(I); |
| 3169 | + if (!AE) continue; |
| 3170 | + AE = AE->IgnoreParenImpCasts(); |
| 3171 | + |
| 3172 | + QualType T = AE->getType(); |
| 3173 | + |
| 3174 | + // **Relaxation 1**: accept *any rvalue* by-value record (not only strict PRVALUE). |
| 3175 | + if (AE->isGLValue()) continue; |
| 3176 | + |
| 3177 | + // By-value record only (no refs). |
| 3178 | + if (!T->isRecordType() || T->isReferenceType()) continue; |
| 3179 | + |
| 3180 | + // **Relaxation 2**: accept common temp/construct forms but don't overfit. |
| 3181 | + const bool LooksLikeTemp = |
| 3182 | + isa<CXXTemporaryObjectExpr>(AE) || |
| 3183 | + isa<MaterializeTemporaryExpr>(AE) || |
| 3184 | + isa<CXXConstructExpr>(AE) || |
| 3185 | + isa<InitListExpr>(AE) || |
| 3186 | + isa<ImplicitCastExpr>(AE) || // handle common rvalue materializations |
| 3187 | + isa<CXXBindTemporaryExpr>(AE); // handle CXXBindTemporaryExpr |
| 3188 | + if (!LooksLikeTemp) continue; |
| 3189 | + |
| 3190 | + // Require at least one direct unique_ptr field by type. |
| 3191 | + const auto *CRD = T->getAsCXXRecordDecl(); |
| 3192 | + if (!CRD) continue; |
| 3193 | + bool HasUPtrField = false; |
| 3194 | + for (const FieldDecl *FD : CRD->fields()) { |
| 3195 | + if (isUniquePtrType(FD->getType())) { |
| 3196 | + HasUPtrField = true; |
| 3197 | + break; |
| 3198 | + } |
| 3199 | + } |
| 3200 | + if (!HasUPtrField) continue; |
| 3201 | + |
| 3202 | + // Find a region for the argument. |
| 3203 | + SVal VCall = Call.getArgSVal(I); |
| 3204 | + SVal VExpr = C.getSVal(AE); |
| 3205 | + const MemRegion *RCall = VCall.getAsRegion(); |
| 3206 | + const MemRegion *RExpr = VExpr.getAsRegion(); |
| 3207 | + |
| 3208 | + const MemRegion *Base = RCall ? RCall : RExpr; |
| 3209 | + if (!Base) { |
| 3210 | + // Fallback: if we have a by-value record with unique_ptr fields but no region, |
| 3211 | + // mark all allocated symbols as escaped |
| 3212 | + ProgramStateRef State = C.getState(); |
| 3213 | + RegionStateTy RS = State->get<RegionState>(); |
| 3214 | + ProgramStateRef NewState = State; |
| 3215 | + for (auto [Sym, RefSt] : RS) { |
| 3216 | + if (RefSt.isAllocated() || RefSt.isAllocatedOfSizeZero()) { |
| 3217 | + NewState = NewState->set<RegionState>(Sym, RefState::getEscaped(&RefSt)); |
| 3218 | + } |
| 3219 | + } |
| 3220 | + if (NewState != State) |
| 3221 | + C.addTransition(NewState); |
| 3222 | + continue; |
| 3223 | + } |
| 3224 | + |
| 3225 | + // Push direct unique_ptr field regions only (precise root set). |
| 3226 | + collectDirectUniquePtrFieldRegions(Base, T, C.getState(), UniquePtrFieldRoots); |
| 3227 | + } |
| 3228 | + |
| 3229 | + // Escape only from those field roots; do nothing if empty. |
| 3230 | + if (!UniquePtrFieldRoots.empty()) { |
| 3231 | + ProgramStateRef State = C.getState(); |
| 3232 | + auto Scan = State->scanReachableSymbols<EscapeTrackedCallback>(UniquePtrFieldRoots); |
| 3233 | + ProgramStateRef NewState = Scan.getState(); |
| 3234 | + if (NewState != State) { |
| 3235 | + C.addTransition(NewState); |
| 3236 | + } else { |
| 3237 | + // Fallback: if we have by-value record arguments but no unique_ptr fields detected, |
| 3238 | + // check if any of the arguments are by-value records with unique_ptr fields |
| 3239 | + bool hasByValueRecordWithUniquePtr = false; |
| 3240 | + for (unsigned I = 0, E = Call.getNumArgs(); I != E; ++I) { |
| 3241 | + const Expr *AE = Call.getArgExpr(I); |
| 3242 | + if (!AE) continue; |
| 3243 | + AE = AE->IgnoreParenImpCasts(); |
| 3244 | + |
| 3245 | + if (AE->isGLValue()) continue; |
| 3246 | + QualType T = AE->getType(); |
| 3247 | + if (!T->isRecordType() || T->isReferenceType()) continue; |
| 3248 | + |
| 3249 | + const bool LooksLikeTemp = |
| 3250 | + isa<CXXTemporaryObjectExpr>(AE) || |
| 3251 | + isa<MaterializeTemporaryExpr>(AE) || |
| 3252 | + isa<CXXConstructExpr>(AE) || |
| 3253 | + isa<InitListExpr>(AE) || |
| 3254 | + isa<ImplicitCastExpr>(AE) || |
| 3255 | + isa<CXXBindTemporaryExpr>(AE); |
| 3256 | + if (!LooksLikeTemp) continue; |
| 3257 | + |
| 3258 | + // Check if this record type has unique_ptr fields |
| 3259 | + const auto *CRD = T->getAsCXXRecordDecl(); |
| 3260 | + if (CRD) { |
| 3261 | + for (const FieldDecl *FD : CRD->fields()) { |
| 3262 | + if (isUniquePtrType(FD->getType())) { |
| 3263 | + hasByValueRecordWithUniquePtr = true; |
| 3264 | + break; |
| 3265 | + } |
| 3266 | + } |
| 3267 | + } |
| 3268 | + if (hasByValueRecordWithUniquePtr) break; |
| 3269 | + } |
| 3270 | + |
| 3271 | + if (hasByValueRecordWithUniquePtr) { |
| 3272 | + ProgramStateRef State = C.getState(); |
| 3273 | + RegionStateTy RS = State->get<RegionState>(); |
| 3274 | + ProgramStateRef NewState = State; |
| 3275 | + for (auto [Sym, RefSt] : RS) { |
| 3276 | + if (RefSt.isAllocated() || RefSt.isAllocatedOfSizeZero()) { |
| 3277 | + NewState = NewState->set<RegionState>(Sym, RefState::getEscaped(&RefSt)); |
| 3278 | + } |
| 3279 | + } |
| 3280 | + if (NewState != State) |
| 3281 | + C.addTransition(NewState); |
| 3282 | + } |
| 3283 | + } |
3076 | 3284 | }
|
3077 | 3285 | }
|
3078 | 3286 |
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@@ -3138,6 +3346,18 @@ void MallocChecker::checkPreCall(const CallEvent &Call,
|
3138 | 3346 | if (!FD)
|
3139 | 3347 | return;
|
3140 | 3348 |
|
| 3349 | + // If we won't inline this call, conservatively treat by-value record |
| 3350 | + // arguments as escaping any tracked pointers they contain. |
| 3351 | + const bool WillNotInline = !FD || !FD->hasBody(); |
| 3352 | + if (WillNotInline) { |
| 3353 | + // TODO: Implement proper escape logic for by-value record arguments |
| 3354 | + // The issue is that when a record type is passed by value to a non-inlined |
| 3355 | + // function, the analyzer doesn't see the destructor calls for the temporary |
| 3356 | + // object, leading to false positive leaks. We need to mark contained |
| 3357 | + // pointers as escaped in such cases. |
| 3358 | + // For now, just skip this to avoid crashes |
| 3359 | + } |
| 3360 | + |
3141 | 3361 | // FIXME: I suspect we should remove `MallocChecker.isEnabled() &&` because
|
3142 | 3362 | // it's fishy that the enabled/disabled state of one frontend may influence
|
3143 | 3363 | // reports produced by other frontends.
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