clang  3.7.0
MacOSKeychainAPIChecker.cpp
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1 //==--- MacOSKeychainAPIChecker.cpp ------------------------------*- C++ -*-==//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 // This checker flags misuses of KeyChainAPI. In particular, the password data
10 // allocated/returned by SecKeychainItemCopyContent,
11 // SecKeychainFindGenericPassword, SecKeychainFindInternetPassword functions has
12 // to be freed using a call to SecKeychainItemFreeContent.
13 //===----------------------------------------------------------------------===//
14 
15 #include "ClangSACheckers.h"
22 #include "llvm/ADT/SmallString.h"
23 #include "llvm/Support/raw_ostream.h"
24 
25 using namespace clang;
26 using namespace ento;
27 
28 namespace {
29 class MacOSKeychainAPIChecker : public Checker<check::PreStmt<CallExpr>,
30  check::PostStmt<CallExpr>,
31  check::DeadSymbols> {
32  mutable std::unique_ptr<BugType> BT;
33 
34 public:
35  /// AllocationState is a part of the checker specific state together with the
36  /// MemRegion corresponding to the allocated data.
37  struct AllocationState {
38  /// The index of the allocator function.
39  unsigned int AllocatorIdx;
40  SymbolRef Region;
41 
42  AllocationState(const Expr *E, unsigned int Idx, SymbolRef R) :
43  AllocatorIdx(Idx),
44  Region(R) {}
45 
46  bool operator==(const AllocationState &X) const {
47  return (AllocatorIdx == X.AllocatorIdx &&
48  Region == X.Region);
49  }
50 
51  void Profile(llvm::FoldingSetNodeID &ID) const {
52  ID.AddInteger(AllocatorIdx);
53  ID.AddPointer(Region);
54  }
55  };
56 
57  void checkPreStmt(const CallExpr *S, CheckerContext &C) const;
58  void checkPostStmt(const CallExpr *S, CheckerContext &C) const;
59  void checkDeadSymbols(SymbolReaper &SR, CheckerContext &C) const;
60 
61 private:
62  typedef std::pair<SymbolRef, const AllocationState*> AllocationPair;
63  typedef SmallVector<AllocationPair, 2> AllocationPairVec;
64 
65  enum APIKind {
66  /// Denotes functions tracked by this checker.
67  ValidAPI = 0,
68  /// The functions commonly/mistakenly used in place of the given API.
69  ErrorAPI = 1,
70  /// The functions which may allocate the data. These are tracked to reduce
71  /// the false alarm rate.
72  PossibleAPI = 2
73  };
74  /// Stores the information about the allocator and deallocator functions -
75  /// these are the functions the checker is tracking.
76  struct ADFunctionInfo {
77  const char* Name;
78  unsigned int Param;
79  unsigned int DeallocatorIdx;
80  APIKind Kind;
81  };
82  static const unsigned InvalidIdx = 100000;
83  static const unsigned FunctionsToTrackSize = 8;
84  static const ADFunctionInfo FunctionsToTrack[FunctionsToTrackSize];
85  /// The value, which represents no error return value for allocator functions.
86  static const unsigned NoErr = 0;
87 
88  /// Given the function name, returns the index of the allocator/deallocator
89  /// function.
90  static unsigned getTrackedFunctionIndex(StringRef Name, bool IsAllocator);
91 
92  inline void initBugType() const {
93  if (!BT)
94  BT.reset(new BugType(this, "Improper use of SecKeychain API",
95  "API Misuse (Apple)"));
96  }
97 
98  void generateDeallocatorMismatchReport(const AllocationPair &AP,
99  const Expr *ArgExpr,
100  CheckerContext &C) const;
101 
102  /// Find the allocation site for Sym on the path leading to the node N.
103  const ExplodedNode *getAllocationNode(const ExplodedNode *N, SymbolRef Sym,
104  CheckerContext &C) const;
105 
106  std::unique_ptr<BugReport> generateAllocatedDataNotReleasedReport(
107  const AllocationPair &AP, ExplodedNode *N, CheckerContext &C) const;
108 
109  /// Check if RetSym evaluates to an error value in the current state.
110  bool definitelyReturnedError(SymbolRef RetSym,
113  bool noError = false) const;
114 
115  /// Check if RetSym evaluates to a NoErr value in the current state.
116  bool definitelyDidnotReturnError(SymbolRef RetSym,
118  SValBuilder &Builder) const {
119  return definitelyReturnedError(RetSym, State, Builder, true);
120  }
121 
122  /// Mark an AllocationPair interesting for diagnostic reporting.
123  void markInteresting(BugReport *R, const AllocationPair &AP) const {
124  R->markInteresting(AP.first);
125  R->markInteresting(AP.second->Region);
126  }
127 
128  /// The bug visitor which allows us to print extra diagnostics along the
129  /// BugReport path. For example, showing the allocation site of the leaked
130  /// region.
131  class SecKeychainBugVisitor
132  : public BugReporterVisitorImpl<SecKeychainBugVisitor> {
133  protected:
134  // The allocated region symbol tracked by the main analysis.
135  SymbolRef Sym;
136 
137  public:
138  SecKeychainBugVisitor(SymbolRef S) : Sym(S) {}
139  ~SecKeychainBugVisitor() override {}
140 
141  void Profile(llvm::FoldingSetNodeID &ID) const override {
142  static int X = 0;
143  ID.AddPointer(&X);
144  ID.AddPointer(Sym);
145  }
146 
147  PathDiagnosticPiece *VisitNode(const ExplodedNode *N,
148  const ExplodedNode *PrevN,
149  BugReporterContext &BRC,
150  BugReport &BR) override;
151  };
152 };
153 }
154 
155 /// ProgramState traits to store the currently allocated (and not yet freed)
156 /// symbols. This is a map from the allocated content symbol to the
157 /// corresponding AllocationState.
159  SymbolRef,
160  MacOSKeychainAPIChecker::AllocationState)
161 
162 static bool isEnclosingFunctionParam(const Expr *E) {
163  E = E->IgnoreParenCasts();
164  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
165  const ValueDecl *VD = DRE->getDecl();
166  if (isa<ImplicitParamDecl>(VD) || isa<ParmVarDecl>(VD))
167  return true;
168  }
169  return false;
170 }
171 
172 const MacOSKeychainAPIChecker::ADFunctionInfo
173  MacOSKeychainAPIChecker::FunctionsToTrack[FunctionsToTrackSize] = {
174  {"SecKeychainItemCopyContent", 4, 3, ValidAPI}, // 0
175  {"SecKeychainFindGenericPassword", 6, 3, ValidAPI}, // 1
176  {"SecKeychainFindInternetPassword", 13, 3, ValidAPI}, // 2
177  {"SecKeychainItemFreeContent", 1, InvalidIdx, ValidAPI}, // 3
178  {"SecKeychainItemCopyAttributesAndData", 5, 5, ValidAPI}, // 4
179  {"SecKeychainItemFreeAttributesAndData", 1, InvalidIdx, ValidAPI}, // 5
180  {"free", 0, InvalidIdx, ErrorAPI}, // 6
181  {"CFStringCreateWithBytesNoCopy", 1, InvalidIdx, PossibleAPI}, // 7
182 };
183 
184 unsigned MacOSKeychainAPIChecker::getTrackedFunctionIndex(StringRef Name,
185  bool IsAllocator) {
186  for (unsigned I = 0; I < FunctionsToTrackSize; ++I) {
187  ADFunctionInfo FI = FunctionsToTrack[I];
188  if (FI.Name != Name)
189  continue;
190  // Make sure the function is of the right type (allocator vs deallocator).
191  if (IsAllocator && (FI.DeallocatorIdx == InvalidIdx))
192  return InvalidIdx;
193  if (!IsAllocator && (FI.DeallocatorIdx != InvalidIdx))
194  return InvalidIdx;
195 
196  return I;
197  }
198  // The function is not tracked.
199  return InvalidIdx;
200 }
201 
202 static bool isBadDeallocationArgument(const MemRegion *Arg) {
203  if (!Arg)
204  return false;
205  if (isa<AllocaRegion>(Arg) ||
206  isa<BlockDataRegion>(Arg) ||
207  isa<TypedRegion>(Arg)) {
208  return true;
209  }
210  return false;
211 }
212 
213 /// Given the address expression, retrieve the value it's pointing to. Assume
214 /// that value is itself an address, and return the corresponding symbol.
216  CheckerContext &C) {
218  SVal ArgV = State->getSVal(Expr, C.getLocationContext());
219 
222  SymbolRef sym = SM.getBinding(State->getStore(), *X).getAsLocSymbol();
223  if (sym)
224  return sym;
225  }
226  return nullptr;
227 }
228 
229 // When checking for error code, we need to consider the following cases:
230 // 1) noErr / [0]
231 // 2) someErr / [1, inf]
232 // 3) unknown
233 // If noError, returns true iff (1).
234 // If !noError, returns true iff (2).
235 bool MacOSKeychainAPIChecker::definitelyReturnedError(SymbolRef RetSym,
238  bool noError) const {
239  DefinedOrUnknownSVal NoErrVal = Builder.makeIntVal(NoErr,
240  Builder.getSymbolManager().getType(RetSym));
241  DefinedOrUnknownSVal NoErr = Builder.evalEQ(State, NoErrVal,
242  nonloc::SymbolVal(RetSym));
243  ProgramStateRef ErrState = State->assume(NoErr, noError);
244  if (ErrState == State) {
245  return true;
246  }
247 
248  return false;
249 }
250 
251 // Report deallocator mismatch. Remove the region from tracking - reporting a
252 // missing free error after this one is redundant.
253 void MacOSKeychainAPIChecker::
254  generateDeallocatorMismatchReport(const AllocationPair &AP,
255  const Expr *ArgExpr,
256  CheckerContext &C) const {
257  ProgramStateRef State = C.getState();
258  State = State->remove<AllocatedData>(AP.first);
259  ExplodedNode *N = C.addTransition(State);
260 
261  if (!N)
262  return;
263  initBugType();
264  SmallString<80> sbuf;
265  llvm::raw_svector_ostream os(sbuf);
266  unsigned int PDeallocIdx =
267  FunctionsToTrack[AP.second->AllocatorIdx].DeallocatorIdx;
268 
269  os << "Deallocator doesn't match the allocator: '"
270  << FunctionsToTrack[PDeallocIdx].Name << "' should be used.";
271  auto Report = llvm::make_unique<BugReport>(*BT, os.str(), N);
272  Report->addVisitor(llvm::make_unique<SecKeychainBugVisitor>(AP.first));
273  Report->addRange(ArgExpr->getSourceRange());
274  markInteresting(Report.get(), AP);
275  C.emitReport(std::move(Report));
276 }
277 
278 void MacOSKeychainAPIChecker::checkPreStmt(const CallExpr *CE,
279  CheckerContext &C) const {
280  unsigned idx = InvalidIdx;
281  ProgramStateRef State = C.getState();
282 
283  const FunctionDecl *FD = C.getCalleeDecl(CE);
284  if (!FD || FD->getKind() != Decl::Function)
285  return;
286 
287  StringRef funName = C.getCalleeName(FD);
288  if (funName.empty())
289  return;
290 
291  // If it is a call to an allocator function, it could be a double allocation.
292  idx = getTrackedFunctionIndex(funName, true);
293  if (idx != InvalidIdx) {
294  unsigned paramIdx = FunctionsToTrack[idx].Param;
295  if (CE->getNumArgs() <= paramIdx)
296  return;
297 
298  const Expr *ArgExpr = CE->getArg(paramIdx);
299  if (SymbolRef V = getAsPointeeSymbol(ArgExpr, C))
300  if (const AllocationState *AS = State->get<AllocatedData>(V)) {
301  if (!definitelyReturnedError(AS->Region, State, C.getSValBuilder())) {
302  // Remove the value from the state. The new symbol will be added for
303  // tracking when the second allocator is processed in checkPostStmt().
304  State = State->remove<AllocatedData>(V);
305  ExplodedNode *N = C.addTransition(State);
306  if (!N)
307  return;
308  initBugType();
309  SmallString<128> sbuf;
310  llvm::raw_svector_ostream os(sbuf);
311  unsigned int DIdx = FunctionsToTrack[AS->AllocatorIdx].DeallocatorIdx;
312  os << "Allocated data should be released before another call to "
313  << "the allocator: missing a call to '"
314  << FunctionsToTrack[DIdx].Name
315  << "'.";
316  auto Report = llvm::make_unique<BugReport>(*BT, os.str(), N);
317  Report->addVisitor(llvm::make_unique<SecKeychainBugVisitor>(V));
318  Report->addRange(ArgExpr->getSourceRange());
319  Report->markInteresting(AS->Region);
320  C.emitReport(std::move(Report));
321  }
322  }
323  return;
324  }
325 
326  // Is it a call to one of deallocator functions?
327  idx = getTrackedFunctionIndex(funName, false);
328  if (idx == InvalidIdx)
329  return;
330 
331  unsigned paramIdx = FunctionsToTrack[idx].Param;
332  if (CE->getNumArgs() <= paramIdx)
333  return;
334 
335  // Check the argument to the deallocator.
336  const Expr *ArgExpr = CE->getArg(paramIdx);
337  SVal ArgSVal = State->getSVal(ArgExpr, C.getLocationContext());
338 
339  // Undef is reported by another checker.
340  if (ArgSVal.isUndef())
341  return;
342 
343  SymbolRef ArgSM = ArgSVal.getAsLocSymbol();
344 
345  // If the argument is coming from the heap, globals, or unknown, do not
346  // report it.
347  bool RegionArgIsBad = false;
348  if (!ArgSM) {
349  if (!isBadDeallocationArgument(ArgSVal.getAsRegion()))
350  return;
351  RegionArgIsBad = true;
352  }
353 
354  // Is the argument to the call being tracked?
355  const AllocationState *AS = State->get<AllocatedData>(ArgSM);
356  if (!AS && FunctionsToTrack[idx].Kind != ValidAPI) {
357  return;
358  }
359  // If trying to free data which has not been allocated yet, report as a bug.
360  // TODO: We might want a more precise diagnostic for double free
361  // (that would involve tracking all the freed symbols in the checker state).
362  if (!AS || RegionArgIsBad) {
363  // It is possible that this is a false positive - the argument might
364  // have entered as an enclosing function parameter.
365  if (isEnclosingFunctionParam(ArgExpr))
366  return;
367 
368  ExplodedNode *N = C.addTransition(State);
369  if (!N)
370  return;
371  initBugType();
372  auto Report = llvm::make_unique<BugReport>(
373  *BT, "Trying to free data which has not been allocated.", N);
374  Report->addRange(ArgExpr->getSourceRange());
375  if (AS)
376  Report->markInteresting(AS->Region);
377  C.emitReport(std::move(Report));
378  return;
379  }
380 
381  // Process functions which might deallocate.
382  if (FunctionsToTrack[idx].Kind == PossibleAPI) {
383 
384  if (funName == "CFStringCreateWithBytesNoCopy") {
385  const Expr *DeallocatorExpr = CE->getArg(5)->IgnoreParenCasts();
386  // NULL ~ default deallocator, so warn.
387  if (DeallocatorExpr->isNullPointerConstant(C.getASTContext(),
389  const AllocationPair AP = std::make_pair(ArgSM, AS);
390  generateDeallocatorMismatchReport(AP, ArgExpr, C);
391  return;
392  }
393  // One of the default allocators, so warn.
394  if (const DeclRefExpr *DE = dyn_cast<DeclRefExpr>(DeallocatorExpr)) {
395  StringRef DeallocatorName = DE->getFoundDecl()->getName();
396  if (DeallocatorName == "kCFAllocatorDefault" ||
397  DeallocatorName == "kCFAllocatorSystemDefault" ||
398  DeallocatorName == "kCFAllocatorMalloc") {
399  const AllocationPair AP = std::make_pair(ArgSM, AS);
400  generateDeallocatorMismatchReport(AP, ArgExpr, C);
401  return;
402  }
403  // If kCFAllocatorNull, which does not deallocate, we still have to
404  // find the deallocator.
405  if (DE->getFoundDecl()->getName() == "kCFAllocatorNull")
406  return;
407  }
408  // In all other cases, assume the user supplied a correct deallocator
409  // that will free memory so stop tracking.
410  State = State->remove<AllocatedData>(ArgSM);
411  C.addTransition(State);
412  return;
413  }
414 
415  llvm_unreachable("We know of no other possible APIs.");
416  }
417 
418  // The call is deallocating a value we previously allocated, so remove it
419  // from the next state.
420  State = State->remove<AllocatedData>(ArgSM);
421 
422  // Check if the proper deallocator is used.
423  unsigned int PDeallocIdx = FunctionsToTrack[AS->AllocatorIdx].DeallocatorIdx;
424  if (PDeallocIdx != idx || (FunctionsToTrack[idx].Kind == ErrorAPI)) {
425  const AllocationPair AP = std::make_pair(ArgSM, AS);
426  generateDeallocatorMismatchReport(AP, ArgExpr, C);
427  return;
428  }
429 
430  // If the buffer can be null and the return status can be an error,
431  // report a bad call to free.
432  if (State->assume(ArgSVal.castAs<DefinedSVal>(), false) &&
433  !definitelyDidnotReturnError(AS->Region, State, C.getSValBuilder())) {
434  ExplodedNode *N = C.addTransition(State);
435  if (!N)
436  return;
437  initBugType();
438  auto Report = llvm::make_unique<BugReport>(
439  *BT, "Only call free if a valid (non-NULL) buffer was returned.", N);
440  Report->addVisitor(llvm::make_unique<SecKeychainBugVisitor>(ArgSM));
441  Report->addRange(ArgExpr->getSourceRange());
442  Report->markInteresting(AS->Region);
443  C.emitReport(std::move(Report));
444  return;
445  }
446 
447  C.addTransition(State);
448 }
449 
450 void MacOSKeychainAPIChecker::checkPostStmt(const CallExpr *CE,
451  CheckerContext &C) const {
452  ProgramStateRef State = C.getState();
453  const FunctionDecl *FD = C.getCalleeDecl(CE);
454  if (!FD || FD->getKind() != Decl::Function)
455  return;
456 
457  StringRef funName = C.getCalleeName(FD);
458 
459  // If a value has been allocated, add it to the set for tracking.
460  unsigned idx = getTrackedFunctionIndex(funName, true);
461  if (idx == InvalidIdx)
462  return;
463 
464  const Expr *ArgExpr = CE->getArg(FunctionsToTrack[idx].Param);
465  // If the argument entered as an enclosing function parameter, skip it to
466  // avoid false positives.
467  if (isEnclosingFunctionParam(ArgExpr) &&
468  C.getLocationContext()->getParent() == nullptr)
469  return;
470 
471  if (SymbolRef V = getAsPointeeSymbol(ArgExpr, C)) {
472  // If the argument points to something that's not a symbolic region, it
473  // can be:
474  // - unknown (cannot reason about it)
475  // - undefined (already reported by other checker)
476  // - constant (null - should not be tracked,
477  // other constant will generate a compiler warning)
478  // - goto (should be reported by other checker)
479 
480  // The call return value symbol should stay alive for as long as the
481  // allocated value symbol, since our diagnostics depend on the value
482  // returned by the call. Ex: Data should only be freed if noErr was
483  // returned during allocation.)
484  SymbolRef RetStatusSymbol =
485  State->getSVal(CE, C.getLocationContext()).getAsSymbol();
486  C.getSymbolManager().addSymbolDependency(V, RetStatusSymbol);
487 
488  // Track the allocated value in the checker state.
489  State = State->set<AllocatedData>(V, AllocationState(ArgExpr, idx,
490  RetStatusSymbol));
491  assert(State);
492  C.addTransition(State);
493  }
494 }
495 
496 // TODO: This logic is the same as in Malloc checker.
497 const ExplodedNode *
498 MacOSKeychainAPIChecker::getAllocationNode(const ExplodedNode *N,
499  SymbolRef Sym,
500  CheckerContext &C) const {
501  const LocationContext *LeakContext = N->getLocationContext();
502  // Walk the ExplodedGraph backwards and find the first node that referred to
503  // the tracked symbol.
504  const ExplodedNode *AllocNode = N;
505 
506  while (N) {
507  if (!N->getState()->get<AllocatedData>(Sym))
508  break;
509  // Allocation node, is the last node in the current or parent context in
510  // which the symbol was tracked.
511  const LocationContext *NContext = N->getLocationContext();
512  if (NContext == LeakContext ||
513  NContext->isParentOf(LeakContext))
514  AllocNode = N;
515  N = N->pred_empty() ? nullptr : *(N->pred_begin());
516  }
517 
518  return AllocNode;
519 }
520 
521 std::unique_ptr<BugReport>
522 MacOSKeychainAPIChecker::generateAllocatedDataNotReleasedReport(
523  const AllocationPair &AP, ExplodedNode *N, CheckerContext &C) const {
524  const ADFunctionInfo &FI = FunctionsToTrack[AP.second->AllocatorIdx];
525  initBugType();
526  SmallString<70> sbuf;
527  llvm::raw_svector_ostream os(sbuf);
528  os << "Allocated data is not released: missing a call to '"
529  << FunctionsToTrack[FI.DeallocatorIdx].Name << "'.";
530 
531  // Most bug reports are cached at the location where they occurred.
532  // With leaks, we want to unique them by the location where they were
533  // allocated, and only report a single path.
534  PathDiagnosticLocation LocUsedForUniqueing;
535  const ExplodedNode *AllocNode = getAllocationNode(N, AP.first, C);
536  const Stmt *AllocStmt = nullptr;
537  ProgramPoint P = AllocNode->getLocation();
538  if (Optional<CallExitEnd> Exit = P.getAs<CallExitEnd>())
539  AllocStmt = Exit->getCalleeContext()->getCallSite();
541  AllocStmt = PS->getStmt();
542 
543  if (AllocStmt)
544  LocUsedForUniqueing = PathDiagnosticLocation::createBegin(AllocStmt,
545  C.getSourceManager(),
546  AllocNode->getLocationContext());
547 
548  auto Report =
549  llvm::make_unique<BugReport>(*BT, os.str(), N, LocUsedForUniqueing,
550  AllocNode->getLocationContext()->getDecl());
551 
552  Report->addVisitor(llvm::make_unique<SecKeychainBugVisitor>(AP.first));
553  markInteresting(Report.get(), AP);
554  return Report;
555 }
556 
557 void MacOSKeychainAPIChecker::checkDeadSymbols(SymbolReaper &SR,
558  CheckerContext &C) const {
559  ProgramStateRef State = C.getState();
560  AllocatedDataTy ASet = State->get<AllocatedData>();
561  if (ASet.isEmpty())
562  return;
563 
564  bool Changed = false;
565  AllocationPairVec Errors;
566  for (AllocatedDataTy::iterator I = ASet.begin(), E = ASet.end(); I != E; ++I) {
567  if (SR.isLive(I->first))
568  continue;
569 
570  Changed = true;
571  State = State->remove<AllocatedData>(I->first);
572  // If the allocated symbol is null or if the allocation call might have
573  // returned an error, do not report.
574  ConstraintManager &CMgr = State->getConstraintManager();
575  ConditionTruthVal AllocFailed = CMgr.isNull(State, I.getKey());
576  if (AllocFailed.isConstrainedTrue() ||
577  definitelyReturnedError(I->second.Region, State, C.getSValBuilder()))
578  continue;
579  Errors.push_back(std::make_pair(I->first, &I->second));
580  }
581  if (!Changed) {
582  // Generate the new, cleaned up state.
583  C.addTransition(State);
584  return;
585  }
586 
587  static CheckerProgramPointTag Tag(this, "DeadSymbolsLeak");
588  ExplodedNode *N = C.addTransition(C.getState(), C.getPredecessor(), &Tag);
589 
590  // Generate the error reports.
591  for (const auto P : Errors)
592  C.emitReport(generateAllocatedDataNotReleasedReport(P, N, C));
593 
594  // Generate the new, cleaned up state.
595  C.addTransition(State, N);
596 }
597 
598 
599 PathDiagnosticPiece *MacOSKeychainAPIChecker::SecKeychainBugVisitor::VisitNode(
600  const ExplodedNode *N,
601  const ExplodedNode *PrevN,
602  BugReporterContext &BRC,
603  BugReport &BR) {
604  const AllocationState *AS = N->getState()->get<AllocatedData>(Sym);
605  if (!AS)
606  return nullptr;
607  const AllocationState *ASPrev = PrevN->getState()->get<AllocatedData>(Sym);
608  if (ASPrev)
609  return nullptr;
610 
611  // (!ASPrev && AS) ~ We started tracking symbol in node N, it must be the
612  // allocation site.
613  const CallExpr *CE =
614  cast<CallExpr>(N->getLocation().castAs<StmtPoint>().getStmt());
615  const FunctionDecl *funDecl = CE->getDirectCallee();
616  assert(funDecl && "We do not support indirect function calls as of now.");
617  StringRef funName = funDecl->getName();
618 
619  // Get the expression of the corresponding argument.
620  unsigned Idx = getTrackedFunctionIndex(funName, true);
621  assert(Idx != InvalidIdx && "This should be a call to an allocator.");
622  const Expr *ArgExpr = CE->getArg(FunctionsToTrack[Idx].Param);
623  PathDiagnosticLocation Pos(ArgExpr, BRC.getSourceManager(),
624  N->getLocationContext());
625  return new PathDiagnosticEventPiece(Pos, "Data is allocated here.");
626 }
627 
628 void ento::registerMacOSKeychainAPIChecker(CheckerManager &mgr) {
629  mgr.registerChecker<MacOSKeychainAPIChecker>();
630 }
nonloc::ConcreteInt makeIntVal(const IntegerLiteral *integer)
Definition: SValBuilder.h:232
StringRef getCalleeName(const FunctionDecl *FunDecl) const
Get the name of the called function (path-sensitive).
SymbolManager & getSymbolManager()
Definition: SValBuilder.h:137
MemRegion - The root abstract class for all memory regions.
Definition: MemRegion.h:77
Expr * getArg(unsigned Arg)
getArg - Return the specified argument.
Definition: Expr.h:2216
bool operator==(CanQual< T > x, CanQual< U > y)
ProgramPoint getLocation() const
getLocation - Returns the edge associated with the given node.
ExplodedNode * addTransition(ProgramStateRef State=nullptr, const ProgramPointTag *Tag=nullptr)
Generates a new transition in the program state graph (ExplodedGraph). Uses the default CheckerContex...
ExplodedNode * getPredecessor()
Returns the previous node in the exploded graph, which includes the state of the program before the c...
virtual SVal getBinding(Store store, Loc loc, QualType T=QualType())=0
NullPointerConstantKind isNullPointerConstant(ASTContext &Ctx, NullPointerConstantValueDependence NPC) const
Definition: Expr.cpp:3225
Symbolic value. These values used to capture symbolic execution of the program.
Definition: SymbolManager.h:42
static SymbolRef getAsPointeeSymbol(const Expr *Expr, CheckerContext &C)
const FunctionDecl * getCalleeDecl(const CallExpr *CE) const
Get the declaration of the called function (path-sensitive).
LineState State
SymbolRef getAsLocSymbol(bool IncludeBaseRegions=false) const
If this SVal is a location and wraps a symbol, return that SymbolRef. Otherwise return 0...
Definition: SVals.cpp:69
void addSymbolDependency(const SymbolRef Primary, const SymbolRef Dependent)
Add artificial symbol dependency.
bool isParentOf(const LocationContext *LC) const
Expr * IgnoreParenCasts() LLVM_READONLY
Definition: Expr.cpp:2439
const LocationContext * getLocationContext() const
AnnotatingParser & P
QualType getType(const SymExpr *SE) const
ID
Defines the set of possible language-specific address spaces.
Definition: AddressSpaces.h:27
SourceManager & SM
const ProgramStateRef & getState() const
const ProgramStateRef & getState() const
Optional< T > getAs() const
Convert to the specified SVal type, returning None if this SVal is not of the desired type...
Definition: SVals.h:86
Kind getKind() const
Definition: DeclBase.h:375
SymbolManager & getSymbolManager()
T castAs() const
Convert to the specified ProgramPoint type, asserting that this ProgramPoint is of the desired type...
Definition: ProgramPoint.h:116
void markInteresting(SymbolRef sym)
void emitReport(std::unique_ptr< BugReport > R)
Emit the diagnostics report.
static PathDiagnosticLocation createBegin(const Decl *D, const SourceManager &SM)
Create a location for the beginning of the declaration.
static bool isBadDeallocationArgument(const MemRegion *Arg)
Kind
CHECKER * registerChecker()
Used to register checkers.
StoreManager & getStoreManager()
Specifies that a value-dependent expression should be considered to never be a null pointer constant...
Definition: Expr.h:666
const Decl * getDecl() const
A class responsible for cleaning up unused symbols.
bool isUndef() const
Definition: SVals.h:121
REGISTER_MAP_WITH_PROGRAMSTATE(AllocatedData, SymbolRef, MacOSKeychainAPIChecker::AllocationState) static bool isEnclosingFunctionParam(const Expr *E)
const LocationContext * getParent() const
FunctionDecl * getDirectCallee()
If the callee is a FunctionDecl, return it. Otherwise return 0.
Definition: Expr.cpp:1184
Represents symbolic expression.
Definition: SVals.h:313
const MemRegion * getAsRegion() const
Definition: SVals.cpp:135
bool isConstrainedTrue() const
Return true if the constraint is perfectly constrained to 'true'.
unsigned getNumArgs() const
Definition: Expr.h:2205
Optional< T > getAs() const
Convert to the specified ProgramPoint type, returning None if this ProgramPoint is not of the desired...
Definition: ProgramPoint.h:127
X
Definition: SemaDecl.cpp:11429
BoundNodesTreeBuilder *const Builder
DefinedOrUnknownSVal evalEQ(ProgramStateRef state, DefinedOrUnknownSVal lhs, DefinedOrUnknownSVal rhs)
pred_iterator pred_begin()
SourceManager & getSourceManager()
SValBuilder & getSValBuilder()
A reference to a declared variable, function, enum, etc. [C99 6.5.1p2].
Definition: Expr.h:899
T castAs() const
Convert to the specified SVal type, asserting that this SVal is of the desired type.
Definition: SVals.h:75
SourceManager & getSourceManager()
Definition: BugReporter.h:550
bool isLive(SymbolRef sym)
const LocationContext * getLocationContext() const