head 1.1; branch 1.1.1; access; symbols netbsd-11-0-RC4:1.1.1.7 netbsd-11-0-RC3:1.1.1.7 netbsd-11-0-RC2:1.1.1.7 netbsd-11-0-RC1:1.1.1.7 perseant-exfatfs-base-20250801:1.1.1.7 netbsd-11:1.1.1.7.0.10 netbsd-11-base:1.1.1.7 netbsd-10-1-RELEASE:1.1.1.7 perseant-exfatfs-base-20240630:1.1.1.7 perseant-exfatfs:1.1.1.7.0.8 perseant-exfatfs-base:1.1.1.7 netbsd-8-3-RELEASE:1.1.1.6 netbsd-9-4-RELEASE:1.1.1.6 netbsd-10-0-RELEASE:1.1.1.7 netbsd-10-0-RC6:1.1.1.7 netbsd-10-0-RC5:1.1.1.7 netbsd-10-0-RC4:1.1.1.7 netbsd-10-0-RC3:1.1.1.7 netbsd-10-0-RC2:1.1.1.7 netbsd-10-0-RC1:1.1.1.7 netbsd-10:1.1.1.7.0.6 netbsd-10-base:1.1.1.7 netbsd-9-3-RELEASE:1.1.1.6 cjep_sun2x:1.1.1.7.0.4 cjep_sun2x-base:1.1.1.7 cjep_staticlib_x-base1:1.1.1.7 netbsd-9-2-RELEASE:1.1.1.6 cjep_staticlib_x:1.1.1.7.0.2 cjep_staticlib_x-base:1.1.1.7 netbsd-9-1-RELEASE:1.1.1.6 phil-wifi-20200421:1.1.1.7 phil-wifi-20200411:1.1.1.7 phil-wifi-20200406:1.1.1.7 netbsd-8-2-RELEASE:1.1.1.6 netbsd-9-0-RELEASE:1.1.1.6 netbsd-9-0-RC2:1.1.1.6 netbsd-9-0-RC1:1.1.1.6 netbsd-9:1.1.1.6.0.16 netbsd-9-base:1.1.1.6 phil-wifi-20190609:1.1.1.6 netbsd-8-1-RELEASE:1.1.1.6 netbsd-8-1-RC1:1.1.1.6 pgoyette-compat-merge-20190127:1.1.1.6 pgoyette-compat-20190127:1.1.1.6 pgoyette-compat-20190118:1.1.1.6 pgoyette-compat-1226:1.1.1.6 pgoyette-compat-1126:1.1.1.6 pgoyette-compat-1020:1.1.1.6 pgoyette-compat-0930:1.1.1.6 pgoyette-compat-0906:1.1.1.6 netbsd-7-2-RELEASE:1.1.1.3.2.1 pgoyette-compat-0728:1.1.1.6 clang-337282:1.1.1.6 netbsd-8-0-RELEASE:1.1.1.6 phil-wifi:1.1.1.6.0.14 phil-wifi-base:1.1.1.6 pgoyette-compat-0625:1.1.1.6 netbsd-8-0-RC2:1.1.1.6 pgoyette-compat-0521:1.1.1.6 pgoyette-compat-0502:1.1.1.6 pgoyette-compat-0422:1.1.1.6 netbsd-8-0-RC1:1.1.1.6 pgoyette-compat-0415:1.1.1.6 pgoyette-compat-0407:1.1.1.6 pgoyette-compat-0330:1.1.1.6 pgoyette-compat-0322:1.1.1.6 pgoyette-compat-0315:1.1.1.6 netbsd-7-1-2-RELEASE:1.1.1.3.2.1 pgoyette-compat:1.1.1.6.0.12 pgoyette-compat-base:1.1.1.6 netbsd-7-1-1-RELEASE:1.1.1.3.2.1 clang-319952:1.1.1.6 matt-nb8-mediatek:1.1.1.6.0.10 matt-nb8-mediatek-base:1.1.1.6 clang-309604:1.1.1.6 perseant-stdc-iso10646:1.1.1.6.0.8 perseant-stdc-iso10646-base:1.1.1.6 netbsd-8:1.1.1.6.0.6 netbsd-8-base:1.1.1.6 prg-localcount2-base3:1.1.1.6 prg-localcount2-base2:1.1.1.6 prg-localcount2-base1:1.1.1.6 prg-localcount2:1.1.1.6.0.4 prg-localcount2-base:1.1.1.6 pgoyette-localcount-20170426:1.1.1.6 bouyer-socketcan-base1:1.1.1.6 pgoyette-localcount-20170320:1.1.1.6 netbsd-7-1:1.1.1.3.2.1.0.6 netbsd-7-1-RELEASE:1.1.1.3.2.1 netbsd-7-1-RC2:1.1.1.3.2.1 clang-294123:1.1.1.6 netbsd-7-nhusb-base-20170116:1.1.1.3.2.1 bouyer-socketcan:1.1.1.6.0.2 bouyer-socketcan-base:1.1.1.6 clang-291444:1.1.1.6 pgoyette-localcount-20170107:1.1.1.5 netbsd-7-1-RC1:1.1.1.3.2.1 pgoyette-localcount-20161104:1.1.1.5 netbsd-7-0-2-RELEASE:1.1.1.3.2.1 localcount-20160914:1.1.1.5 netbsd-7-nhusb:1.1.1.3.2.1.0.4 netbsd-7-nhusb-base:1.1.1.3.2.1 clang-280599:1.1.1.5 pgoyette-localcount-20160806:1.1.1.5 pgoyette-localcount-20160726:1.1.1.5 pgoyette-localcount:1.1.1.5.0.2 pgoyette-localcount-base:1.1.1.5 netbsd-7-0-1-RELEASE:1.1.1.3.2.1 clang-261930:1.1.1.5 netbsd-7-0:1.1.1.3.2.1.0.2 netbsd-7-0-RELEASE:1.1.1.3.2.1 netbsd-7-0-RC3:1.1.1.3.2.1 netbsd-7-0-RC2:1.1.1.3.2.1 netbsd-7-0-RC1:1.1.1.3.2.1 clang-237755:1.1.1.4 clang-232565:1.1.1.4 clang-227398:1.1.1.4 tls-maxphys-base:1.1.1.3 tls-maxphys:1.1.1.3.0.4 netbsd-7:1.1.1.3.0.2 netbsd-7-base:1.1.1.3 clang-215315:1.1.1.3 clang-209886:1.1.1.3 yamt-pagecache:1.1.1.2.0.4 yamt-pagecache-base9:1.1.1.2 tls-earlyentropy:1.1.1.2.0.2 tls-earlyentropy-base:1.1.1.3 riastradh-xf86-video-intel-2-7-1-pre-2-21-15:1.1.1.2 riastradh-drm2-base3:1.1.1.2 clang-202566:1.1.1.2 clang-201163:1.1.1.1 clang-199312:1.1.1.1 clang-198450:1.1.1.1 clang-196603:1.1.1.1 clang-195771:1.1.1.1 LLVM:1.1.1; locks; strict; comment @// @; 1.1 date 2013.11.28.14.14.52; author joerg; state Exp; branches 1.1.1.1; next ; commitid ow8OybrawrB1f3fx; 1.1.1.1 date 2013.11.28.14.14.52; author joerg; state Exp; branches; next 1.1.1.2; commitid ow8OybrawrB1f3fx; 1.1.1.2 date 2014.03.04.19.55.00; author joerg; state Exp; branches 1.1.1.2.2.1 1.1.1.2.4.1; next 1.1.1.3; commitid 29z1hJonZISIXprx; 1.1.1.3 date 2014.05.30.18.14.44; author joerg; state Exp; branches 1.1.1.3.2.1 1.1.1.3.4.1; next 1.1.1.4; commitid 8q0kdlBlCn09GACx; 1.1.1.4 date 2015.01.29.19.57.30; author joerg; state Exp; branches; next 1.1.1.5; commitid mlISSizlPKvepX7y; 1.1.1.5 date 2016.02.27.22.12.06; author joerg; state Exp; branches 1.1.1.5.2.1; next 1.1.1.6; commitid tIimz3oDlh1NpBWy; 1.1.1.6 date 2017.01.11.10.35.39; author joerg; state Exp; branches 1.1.1.6.14.1; next 1.1.1.7; commitid CNnUNfII1jgNmxBz; 1.1.1.7 date 2019.11.13.22.19.28; author joerg; state dead; branches; next ; commitid QD8YATxuNG34YJKB; 1.1.1.2.2.1 date 2014.08.10.07.08.10; author tls; state Exp; branches; next ; commitid t01A1TLTYxkpGMLx; 1.1.1.2.4.1 date 2014.03.04.19.55.00; author yamt; state dead; branches; next 1.1.1.2.4.2; commitid WSrDtL5nYAUyiyBx; 1.1.1.2.4.2 date 2014.05.22.16.18.31; author yamt; state Exp; branches; next ; commitid WSrDtL5nYAUyiyBx; 1.1.1.3.2.1 date 2015.06.04.20.04.30; author snj; state Exp; branches; next ; commitid yRnjq9fueSo6n9oy; 1.1.1.3.4.1 date 2014.05.30.18.14.44; author tls; state dead; branches; next 1.1.1.3.4.2; commitid jTnpym9Qu0o4R1Nx; 1.1.1.3.4.2 date 2014.08.19.23.47.31; author tls; state Exp; branches; next ; commitid jTnpym9Qu0o4R1Nx; 1.1.1.5.2.1 date 2017.03.20.06.52.42; author pgoyette; state Exp; branches; next ; commitid jjw7cAwgyKq7RfKz; 1.1.1.6.14.1 date 2020.04.13.07.46.39; author martin; state dead; branches; next ; commitid X01YhRUPVUDaec4C; desc @@ 1.1 log @Initial revision @ text @//===-- SimpleStreamChecker.cpp -----------------------------------------*- C++ -*--// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // Defines a checker for proper use of fopen/fclose APIs. // - If a file has been closed with fclose, it should not be accessed again. // Accessing a closed file results in undefined behavior. // - If a file was opened with fopen, it must be closed with fclose before // the execution ends. Failing to do so results in a resource leak. // //===----------------------------------------------------------------------===// #include "ClangSACheckers.h" #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" #include "clang/StaticAnalyzer/Core/Checker.h" #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h" #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h" using namespace clang; using namespace ento; namespace { typedef SmallVector SymbolVector; struct StreamState { private: enum Kind { Opened, Closed } K; StreamState(Kind InK) : K(InK) { } public: bool isOpened() const { return K == Opened; } bool isClosed() const { return K == Closed; } static StreamState getOpened() { return StreamState(Opened); } static StreamState getClosed() { return StreamState(Closed); } bool operator==(const StreamState &X) const { return K == X.K; } void Profile(llvm::FoldingSetNodeID &ID) const { ID.AddInteger(K); } }; class SimpleStreamChecker : public Checker { mutable IdentifierInfo *IIfopen, *IIfclose; OwningPtr DoubleCloseBugType; OwningPtr LeakBugType; void initIdentifierInfo(ASTContext &Ctx) const; void reportDoubleClose(SymbolRef FileDescSym, const CallEvent &Call, CheckerContext &C) const; void reportLeaks(SymbolVector LeakedStreams, CheckerContext &C, ExplodedNode *ErrNode) const; bool guaranteedNotToCloseFile(const CallEvent &Call) const; public: SimpleStreamChecker(); /// Process fopen. void checkPostCall(const CallEvent &Call, CheckerContext &C) const; /// Process fclose. void checkPreCall(const CallEvent &Call, CheckerContext &C) const; void checkDeadSymbols(SymbolReaper &SymReaper, CheckerContext &C) const; /// Stop tracking addresses which escape. ProgramStateRef checkPointerEscape(ProgramStateRef State, const InvalidatedSymbols &Escaped, const CallEvent *Call, PointerEscapeKind Kind) const; }; } // end anonymous namespace /// The state of the checker is a map from tracked stream symbols to their /// state. Let's store it in the ProgramState. REGISTER_MAP_WITH_PROGRAMSTATE(StreamMap, SymbolRef, StreamState) namespace { class StopTrackingCallback : public SymbolVisitor { ProgramStateRef state; public: StopTrackingCallback(ProgramStateRef st) : state(st) {} ProgramStateRef getState() const { return state; } bool VisitSymbol(SymbolRef sym) { state = state->remove(sym); return true; } }; } // end anonymous namespace SimpleStreamChecker::SimpleStreamChecker() : IIfopen(0), IIfclose(0) { // Initialize the bug types. DoubleCloseBugType.reset(new BugType("Double fclose", "Unix Stream API Error")); LeakBugType.reset(new BugType("Resource Leak", "Unix Stream API Error")); // Sinks are higher importance bugs as well as calls to assert() or exit(0). LeakBugType->setSuppressOnSink(true); } void SimpleStreamChecker::checkPostCall(const CallEvent &Call, CheckerContext &C) const { initIdentifierInfo(C.getASTContext()); if (!Call.isGlobalCFunction()) return; if (Call.getCalleeIdentifier() != IIfopen) return; // Get the symbolic value corresponding to the file handle. SymbolRef FileDesc = Call.getReturnValue().getAsSymbol(); if (!FileDesc) return; // Generate the next transition (an edge in the exploded graph). ProgramStateRef State = C.getState(); State = State->set(FileDesc, StreamState::getOpened()); C.addTransition(State); } void SimpleStreamChecker::checkPreCall(const CallEvent &Call, CheckerContext &C) const { initIdentifierInfo(C.getASTContext()); if (!Call.isGlobalCFunction()) return; if (Call.getCalleeIdentifier() != IIfclose) return; if (Call.getNumArgs() != 1) return; // Get the symbolic value corresponding to the file handle. SymbolRef FileDesc = Call.getArgSVal(0).getAsSymbol(); if (!FileDesc) return; // Check if the stream has already been closed. ProgramStateRef State = C.getState(); const StreamState *SS = State->get(FileDesc); if (SS && SS->isClosed()) { reportDoubleClose(FileDesc, Call, C); return; } // Generate the next transition, in which the stream is closed. State = State->set(FileDesc, StreamState::getClosed()); C.addTransition(State); } static bool isLeaked(SymbolRef Sym, const StreamState &SS, bool IsSymDead, ProgramStateRef State) { if (IsSymDead && SS.isOpened()) { // If a symbol is NULL, assume that fopen failed on this path. // A symbol should only be considered leaked if it is non-null. ConstraintManager &CMgr = State->getConstraintManager(); ConditionTruthVal OpenFailed = CMgr.isNull(State, Sym); return !OpenFailed.isConstrainedTrue(); } return false; } void SimpleStreamChecker::checkDeadSymbols(SymbolReaper &SymReaper, CheckerContext &C) const { ProgramStateRef State = C.getState(); SymbolVector LeakedStreams; StreamMapTy TrackedStreams = State->get(); for (StreamMapTy::iterator I = TrackedStreams.begin(), E = TrackedStreams.end(); I != E; ++I) { SymbolRef Sym = I->first; bool IsSymDead = SymReaper.isDead(Sym); // Collect leaked symbols. if (isLeaked(Sym, I->second, IsSymDead, State)) LeakedStreams.push_back(Sym); // Remove the dead symbol from the streams map. if (IsSymDead) State = State->remove(Sym); } ExplodedNode *N = C.addTransition(State); reportLeaks(LeakedStreams, C, N); } void SimpleStreamChecker::reportDoubleClose(SymbolRef FileDescSym, const CallEvent &Call, CheckerContext &C) const { // We reached a bug, stop exploring the path here by generating a sink. ExplodedNode *ErrNode = C.generateSink(); // If we've already reached this node on another path, return. if (!ErrNode) return; // Generate the report. BugReport *R = new BugReport(*DoubleCloseBugType, "Closing a previously closed file stream", ErrNode); R->addRange(Call.getSourceRange()); R->markInteresting(FileDescSym); C.emitReport(R); } void SimpleStreamChecker::reportLeaks(SymbolVector LeakedStreams, CheckerContext &C, ExplodedNode *ErrNode) const { // Attach bug reports to the leak node. // TODO: Identify the leaked file descriptor. for (SmallVectorImpl::iterator I = LeakedStreams.begin(), E = LeakedStreams.end(); I != E; ++I) { BugReport *R = new BugReport(*LeakBugType, "Opened file is never closed; potential resource leak", ErrNode); R->markInteresting(*I); C.emitReport(R); } } bool SimpleStreamChecker::guaranteedNotToCloseFile(const CallEvent &Call) const{ // If it's not in a system header, assume it might close a file. if (!Call.isInSystemHeader()) return false; // Handle cases where we know a buffer's /address/ can escape. if (Call.argumentsMayEscape()) return false; // Note, even though fclose closes the file, we do not list it here // since the checker is modeling the call. return true; } // If the pointer we are tracking escaped, do not track the symbol as // we cannot reason about it anymore. ProgramStateRef SimpleStreamChecker::checkPointerEscape(ProgramStateRef State, const InvalidatedSymbols &Escaped, const CallEvent *Call, PointerEscapeKind Kind) const { // If we know that the call cannot close a file, there is nothing to do. if (Kind == PSK_DirectEscapeOnCall && guaranteedNotToCloseFile(*Call)) { return State; } for (InvalidatedSymbols::const_iterator I = Escaped.begin(), E = Escaped.end(); I != E; ++I) { SymbolRef Sym = *I; // The symbol escaped. Optimistically, assume that the corresponding file // handle will be closed somewhere else. State = State->remove(Sym); } return State; } void SimpleStreamChecker::initIdentifierInfo(ASTContext &Ctx) const { if (IIfopen) return; IIfopen = &Ctx.Idents.get("fopen"); IIfclose = &Ctx.Idents.get("fclose"); } void ento::registerSimpleStreamChecker(CheckerManager &mgr) { mgr.registerChecker(); } @ 1.1.1.1 log @Import Clang 3.4rc1 r195771. @ text @@ 1.1.1.2 log @Import Clang 3.5svn r202566. @ text @d112 2 a113 2 DoubleCloseBugType.reset( new BugType(this, "Double fclose", "Unix Stream API Error")); d115 2 a116 2 LeakBugType.reset( new BugType(this, "Resource Leak", "Unix Stream API Error")); @ 1.1.1.2.2.1 log @Rebase. @ text @d57 2 a58 2 std::unique_ptr DoubleCloseBugType; std::unique_ptr LeakBugType; d102 1 a102 1 bool VisitSymbol(SymbolRef sym) override { d109 2 a110 2 SimpleStreamChecker::SimpleStreamChecker() : IIfopen(nullptr), IIfclose(nullptr) { @ 1.1.1.3 log @Import Clang 3.5svn r209886. @ text @d57 2 a58 2 std::unique_ptr DoubleCloseBugType; std::unique_ptr LeakBugType; d102 1 a102 1 bool VisitSymbol(SymbolRef sym) override { d109 2 a110 2 SimpleStreamChecker::SimpleStreamChecker() : IIfopen(nullptr), IIfclose(nullptr) { @ 1.1.1.3.2.1 log @Update LLVM to 3.6.1, requested by joerg in ticket 824. @ text @d66 2 a67 1 void reportLeaks(ArrayRef LeakedStreams, CheckerContext &C, d225 3 a227 3 void SimpleStreamChecker::reportLeaks(ArrayRef LeakedStreams, CheckerContext &C, ExplodedNode *ErrNode) const { d230 2 a231 1 for (SymbolRef LeakedStream : LeakedStreams) { d234 1 a234 1 R->markInteresting(LeakedStream); @ 1.1.1.4 log @Import Clang 3.6RC1 r227398. @ text @d66 2 a67 1 void reportLeaks(ArrayRef LeakedStreams, CheckerContext &C, d225 3 a227 3 void SimpleStreamChecker::reportLeaks(ArrayRef LeakedStreams, CheckerContext &C, ExplodedNode *ErrNode) const { d230 2 a231 1 for (SymbolRef LeakedStream : LeakedStreams) { d234 1 a234 1 R->markInteresting(LeakedStream); @ 1.1.1.5 log @Import Clang 3.8.0rc3 r261930. @ text @d95 1 a95 1 class StopTrackingCallback final : public SymbolVisitor { d203 1 a203 3 ExplodedNode *N = C.generateNonFatalErrorNode(State); if (!N) return; d211 1 a211 1 ExplodedNode *ErrNode = C.generateErrorNode(); d217 1 a217 1 auto R = llvm::make_unique(*DoubleCloseBugType, d221 1 a221 1 C.emitReport(std::move(R)); d230 1 a230 1 auto R = llvm::make_unique(*LeakBugType, d233 1 a233 1 C.emitReport(std::move(R)); @ 1.1.1.5.2.1 log @Sync with HEAD @ text @a22 1 #include d54 2 a55 1 CallDescription OpenFn, CloseFn; d60 2 d98 1 a98 1 StopTrackingCallback(ProgramStateRef st) : state(std::move(st)) {} d109 1 a109 1 : OpenFn("fopen"), CloseFn("fclose", 1) { d122 2 d127 1 a127 1 if (!Call.isCalled(OpenFn)) d143 2 d148 4 a151 1 if (!Call.isCalled(CloseFn)) d278 7 @ 1.1.1.6 log @Import Clang pre-4.0.0 r291444. @ text @a22 1 #include d54 2 a55 1 CallDescription OpenFn, CloseFn; d60 2 d98 1 a98 1 StopTrackingCallback(ProgramStateRef st) : state(std::move(st)) {} d109 1 a109 1 : OpenFn("fopen"), CloseFn("fclose", 1) { d122 2 d127 1 a127 1 if (!Call.isCalled(OpenFn)) d143 2 d148 4 a151 1 if (!Call.isCalled(CloseFn)) d278 7 @ 1.1.1.6.14.1 log @Mostly merge changes from HEAD upto 20200411 @ text @@ 1.1.1.7 log @Mark old LLVM instance as dead. @ text @@ 1.1.1.3.4.1 log @file SimpleStreamChecker.cpp was added on branch tls-maxphys on 2014-08-19 23:47:31 +0000 @ text @d1 287 @ 1.1.1.3.4.2 log @Rebase to HEAD as of a few days ago. @ text @a0 287 //===-- SimpleStreamChecker.cpp -----------------------------------------*- C++ -*--// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // Defines a checker for proper use of fopen/fclose APIs. // - If a file has been closed with fclose, it should not be accessed again. // Accessing a closed file results in undefined behavior. // - If a file was opened with fopen, it must be closed with fclose before // the execution ends. Failing to do so results in a resource leak. // //===----------------------------------------------------------------------===// #include "ClangSACheckers.h" #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" #include "clang/StaticAnalyzer/Core/Checker.h" #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h" #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h" using namespace clang; using namespace ento; namespace { typedef SmallVector SymbolVector; struct StreamState { private: enum Kind { Opened, Closed } K; StreamState(Kind InK) : K(InK) { } public: bool isOpened() const { return K == Opened; } bool isClosed() const { return K == Closed; } static StreamState getOpened() { return StreamState(Opened); } static StreamState getClosed() { return StreamState(Closed); } bool operator==(const StreamState &X) const { return K == X.K; } void Profile(llvm::FoldingSetNodeID &ID) const { ID.AddInteger(K); } }; class SimpleStreamChecker : public Checker { mutable IdentifierInfo *IIfopen, *IIfclose; std::unique_ptr DoubleCloseBugType; std::unique_ptr LeakBugType; void initIdentifierInfo(ASTContext &Ctx) const; void reportDoubleClose(SymbolRef FileDescSym, const CallEvent &Call, CheckerContext &C) const; void reportLeaks(SymbolVector LeakedStreams, CheckerContext &C, ExplodedNode *ErrNode) const; bool guaranteedNotToCloseFile(const CallEvent &Call) const; public: SimpleStreamChecker(); /// Process fopen. void checkPostCall(const CallEvent &Call, CheckerContext &C) const; /// Process fclose. void checkPreCall(const CallEvent &Call, CheckerContext &C) const; void checkDeadSymbols(SymbolReaper &SymReaper, CheckerContext &C) const; /// Stop tracking addresses which escape. ProgramStateRef checkPointerEscape(ProgramStateRef State, const InvalidatedSymbols &Escaped, const CallEvent *Call, PointerEscapeKind Kind) const; }; } // end anonymous namespace /// The state of the checker is a map from tracked stream symbols to their /// state. Let's store it in the ProgramState. REGISTER_MAP_WITH_PROGRAMSTATE(StreamMap, SymbolRef, StreamState) namespace { class StopTrackingCallback : public SymbolVisitor { ProgramStateRef state; public: StopTrackingCallback(ProgramStateRef st) : state(st) {} ProgramStateRef getState() const { return state; } bool VisitSymbol(SymbolRef sym) override { state = state->remove(sym); return true; } }; } // end anonymous namespace SimpleStreamChecker::SimpleStreamChecker() : IIfopen(nullptr), IIfclose(nullptr) { // Initialize the bug types. DoubleCloseBugType.reset( new BugType(this, "Double fclose", "Unix Stream API Error")); LeakBugType.reset( new BugType(this, "Resource Leak", "Unix Stream API Error")); // Sinks are higher importance bugs as well as calls to assert() or exit(0). LeakBugType->setSuppressOnSink(true); } void SimpleStreamChecker::checkPostCall(const CallEvent &Call, CheckerContext &C) const { initIdentifierInfo(C.getASTContext()); if (!Call.isGlobalCFunction()) return; if (Call.getCalleeIdentifier() != IIfopen) return; // Get the symbolic value corresponding to the file handle. SymbolRef FileDesc = Call.getReturnValue().getAsSymbol(); if (!FileDesc) return; // Generate the next transition (an edge in the exploded graph). ProgramStateRef State = C.getState(); State = State->set(FileDesc, StreamState::getOpened()); C.addTransition(State); } void SimpleStreamChecker::checkPreCall(const CallEvent &Call, CheckerContext &C) const { initIdentifierInfo(C.getASTContext()); if (!Call.isGlobalCFunction()) return; if (Call.getCalleeIdentifier() != IIfclose) return; if (Call.getNumArgs() != 1) return; // Get the symbolic value corresponding to the file handle. SymbolRef FileDesc = Call.getArgSVal(0).getAsSymbol(); if (!FileDesc) return; // Check if the stream has already been closed. ProgramStateRef State = C.getState(); const StreamState *SS = State->get(FileDesc); if (SS && SS->isClosed()) { reportDoubleClose(FileDesc, Call, C); return; } // Generate the next transition, in which the stream is closed. State = State->set(FileDesc, StreamState::getClosed()); C.addTransition(State); } static bool isLeaked(SymbolRef Sym, const StreamState &SS, bool IsSymDead, ProgramStateRef State) { if (IsSymDead && SS.isOpened()) { // If a symbol is NULL, assume that fopen failed on this path. // A symbol should only be considered leaked if it is non-null. ConstraintManager &CMgr = State->getConstraintManager(); ConditionTruthVal OpenFailed = CMgr.isNull(State, Sym); return !OpenFailed.isConstrainedTrue(); } return false; } void SimpleStreamChecker::checkDeadSymbols(SymbolReaper &SymReaper, CheckerContext &C) const { ProgramStateRef State = C.getState(); SymbolVector LeakedStreams; StreamMapTy TrackedStreams = State->get(); for (StreamMapTy::iterator I = TrackedStreams.begin(), E = TrackedStreams.end(); I != E; ++I) { SymbolRef Sym = I->first; bool IsSymDead = SymReaper.isDead(Sym); // Collect leaked symbols. if (isLeaked(Sym, I->second, IsSymDead, State)) LeakedStreams.push_back(Sym); // Remove the dead symbol from the streams map. if (IsSymDead) State = State->remove(Sym); } ExplodedNode *N = C.addTransition(State); reportLeaks(LeakedStreams, C, N); } void SimpleStreamChecker::reportDoubleClose(SymbolRef FileDescSym, const CallEvent &Call, CheckerContext &C) const { // We reached a bug, stop exploring the path here by generating a sink. ExplodedNode *ErrNode = C.generateSink(); // If we've already reached this node on another path, return. if (!ErrNode) return; // Generate the report. BugReport *R = new BugReport(*DoubleCloseBugType, "Closing a previously closed file stream", ErrNode); R->addRange(Call.getSourceRange()); R->markInteresting(FileDescSym); C.emitReport(R); } void SimpleStreamChecker::reportLeaks(SymbolVector LeakedStreams, CheckerContext &C, ExplodedNode *ErrNode) const { // Attach bug reports to the leak node. // TODO: Identify the leaked file descriptor. for (SmallVectorImpl::iterator I = LeakedStreams.begin(), E = LeakedStreams.end(); I != E; ++I) { BugReport *R = new BugReport(*LeakBugType, "Opened file is never closed; potential resource leak", ErrNode); R->markInteresting(*I); C.emitReport(R); } } bool SimpleStreamChecker::guaranteedNotToCloseFile(const CallEvent &Call) const{ // If it's not in a system header, assume it might close a file. if (!Call.isInSystemHeader()) return false; // Handle cases where we know a buffer's /address/ can escape. if (Call.argumentsMayEscape()) return false; // Note, even though fclose closes the file, we do not list it here // since the checker is modeling the call. return true; } // If the pointer we are tracking escaped, do not track the symbol as // we cannot reason about it anymore. ProgramStateRef SimpleStreamChecker::checkPointerEscape(ProgramStateRef State, const InvalidatedSymbols &Escaped, const CallEvent *Call, PointerEscapeKind Kind) const { // If we know that the call cannot close a file, there is nothing to do. if (Kind == PSK_DirectEscapeOnCall && guaranteedNotToCloseFile(*Call)) { return State; } for (InvalidatedSymbols::const_iterator I = Escaped.begin(), E = Escaped.end(); I != E; ++I) { SymbolRef Sym = *I; // The symbol escaped. Optimistically, assume that the corresponding file // handle will be closed somewhere else. State = State->remove(Sym); } return State; } void SimpleStreamChecker::initIdentifierInfo(ASTContext &Ctx) const { if (IIfopen) return; IIfopen = &Ctx.Idents.get("fopen"); IIfclose = &Ctx.Idents.get("fclose"); } void ento::registerSimpleStreamChecker(CheckerManager &mgr) { mgr.registerChecker(); } @ 1.1.1.2.4.1 log @file SimpleStreamChecker.cpp was added on branch yamt-pagecache on 2014-05-22 16:18:31 +0000 @ text @d1 287 @ 1.1.1.2.4.2 log @sync with head. for a reference, the tree before this commit was tagged as yamt-pagecache-tag8. this commit was splitted into small chunks to avoid a limitation of cvs. ("Protocol error: too many arguments") @ text @a0 287 //===-- SimpleStreamChecker.cpp -----------------------------------------*- C++ -*--// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // Defines a checker for proper use of fopen/fclose APIs. // - If a file has been closed with fclose, it should not be accessed again. // Accessing a closed file results in undefined behavior. // - If a file was opened with fopen, it must be closed with fclose before // the execution ends. Failing to do so results in a resource leak. // //===----------------------------------------------------------------------===// #include "ClangSACheckers.h" #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" #include "clang/StaticAnalyzer/Core/Checker.h" #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h" #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h" using namespace clang; using namespace ento; namespace { typedef SmallVector SymbolVector; struct StreamState { private: enum Kind { Opened, Closed } K; StreamState(Kind InK) : K(InK) { } public: bool isOpened() const { return K == Opened; } bool isClosed() const { return K == Closed; } static StreamState getOpened() { return StreamState(Opened); } static StreamState getClosed() { return StreamState(Closed); } bool operator==(const StreamState &X) const { return K == X.K; } void Profile(llvm::FoldingSetNodeID &ID) const { ID.AddInteger(K); } }; class SimpleStreamChecker : public Checker { mutable IdentifierInfo *IIfopen, *IIfclose; OwningPtr DoubleCloseBugType; OwningPtr LeakBugType; void initIdentifierInfo(ASTContext &Ctx) const; void reportDoubleClose(SymbolRef FileDescSym, const CallEvent &Call, CheckerContext &C) const; void reportLeaks(SymbolVector LeakedStreams, CheckerContext &C, ExplodedNode *ErrNode) const; bool guaranteedNotToCloseFile(const CallEvent &Call) const; public: SimpleStreamChecker(); /// Process fopen. void checkPostCall(const CallEvent &Call, CheckerContext &C) const; /// Process fclose. void checkPreCall(const CallEvent &Call, CheckerContext &C) const; void checkDeadSymbols(SymbolReaper &SymReaper, CheckerContext &C) const; /// Stop tracking addresses which escape. ProgramStateRef checkPointerEscape(ProgramStateRef State, const InvalidatedSymbols &Escaped, const CallEvent *Call, PointerEscapeKind Kind) const; }; } // end anonymous namespace /// The state of the checker is a map from tracked stream symbols to their /// state. Let's store it in the ProgramState. REGISTER_MAP_WITH_PROGRAMSTATE(StreamMap, SymbolRef, StreamState) namespace { class StopTrackingCallback : public SymbolVisitor { ProgramStateRef state; public: StopTrackingCallback(ProgramStateRef st) : state(st) {} ProgramStateRef getState() const { return state; } bool VisitSymbol(SymbolRef sym) { state = state->remove(sym); return true; } }; } // end anonymous namespace SimpleStreamChecker::SimpleStreamChecker() : IIfopen(0), IIfclose(0) { // Initialize the bug types. DoubleCloseBugType.reset( new BugType(this, "Double fclose", "Unix Stream API Error")); LeakBugType.reset( new BugType(this, "Resource Leak", "Unix Stream API Error")); // Sinks are higher importance bugs as well as calls to assert() or exit(0). LeakBugType->setSuppressOnSink(true); } void SimpleStreamChecker::checkPostCall(const CallEvent &Call, CheckerContext &C) const { initIdentifierInfo(C.getASTContext()); if (!Call.isGlobalCFunction()) return; if (Call.getCalleeIdentifier() != IIfopen) return; // Get the symbolic value corresponding to the file handle. SymbolRef FileDesc = Call.getReturnValue().getAsSymbol(); if (!FileDesc) return; // Generate the next transition (an edge in the exploded graph). ProgramStateRef State = C.getState(); State = State->set(FileDesc, StreamState::getOpened()); C.addTransition(State); } void SimpleStreamChecker::checkPreCall(const CallEvent &Call, CheckerContext &C) const { initIdentifierInfo(C.getASTContext()); if (!Call.isGlobalCFunction()) return; if (Call.getCalleeIdentifier() != IIfclose) return; if (Call.getNumArgs() != 1) return; // Get the symbolic value corresponding to the file handle. SymbolRef FileDesc = Call.getArgSVal(0).getAsSymbol(); if (!FileDesc) return; // Check if the stream has already been closed. ProgramStateRef State = C.getState(); const StreamState *SS = State->get(FileDesc); if (SS && SS->isClosed()) { reportDoubleClose(FileDesc, Call, C); return; } // Generate the next transition, in which the stream is closed. State = State->set(FileDesc, StreamState::getClosed()); C.addTransition(State); } static bool isLeaked(SymbolRef Sym, const StreamState &SS, bool IsSymDead, ProgramStateRef State) { if (IsSymDead && SS.isOpened()) { // If a symbol is NULL, assume that fopen failed on this path. // A symbol should only be considered leaked if it is non-null. ConstraintManager &CMgr = State->getConstraintManager(); ConditionTruthVal OpenFailed = CMgr.isNull(State, Sym); return !OpenFailed.isConstrainedTrue(); } return false; } void SimpleStreamChecker::checkDeadSymbols(SymbolReaper &SymReaper, CheckerContext &C) const { ProgramStateRef State = C.getState(); SymbolVector LeakedStreams; StreamMapTy TrackedStreams = State->get(); for (StreamMapTy::iterator I = TrackedStreams.begin(), E = TrackedStreams.end(); I != E; ++I) { SymbolRef Sym = I->first; bool IsSymDead = SymReaper.isDead(Sym); // Collect leaked symbols. if (isLeaked(Sym, I->second, IsSymDead, State)) LeakedStreams.push_back(Sym); // Remove the dead symbol from the streams map. if (IsSymDead) State = State->remove(Sym); } ExplodedNode *N = C.addTransition(State); reportLeaks(LeakedStreams, C, N); } void SimpleStreamChecker::reportDoubleClose(SymbolRef FileDescSym, const CallEvent &Call, CheckerContext &C) const { // We reached a bug, stop exploring the path here by generating a sink. ExplodedNode *ErrNode = C.generateSink(); // If we've already reached this node on another path, return. if (!ErrNode) return; // Generate the report. BugReport *R = new BugReport(*DoubleCloseBugType, "Closing a previously closed file stream", ErrNode); R->addRange(Call.getSourceRange()); R->markInteresting(FileDescSym); C.emitReport(R); } void SimpleStreamChecker::reportLeaks(SymbolVector LeakedStreams, CheckerContext &C, ExplodedNode *ErrNode) const { // Attach bug reports to the leak node. // TODO: Identify the leaked file descriptor. for (SmallVectorImpl::iterator I = LeakedStreams.begin(), E = LeakedStreams.end(); I != E; ++I) { BugReport *R = new BugReport(*LeakBugType, "Opened file is never closed; potential resource leak", ErrNode); R->markInteresting(*I); C.emitReport(R); } } bool SimpleStreamChecker::guaranteedNotToCloseFile(const CallEvent &Call) const{ // If it's not in a system header, assume it might close a file. if (!Call.isInSystemHeader()) return false; // Handle cases where we know a buffer's /address/ can escape. if (Call.argumentsMayEscape()) return false; // Note, even though fclose closes the file, we do not list it here // since the checker is modeling the call. return true; } // If the pointer we are tracking escaped, do not track the symbol as // we cannot reason about it anymore. ProgramStateRef SimpleStreamChecker::checkPointerEscape(ProgramStateRef State, const InvalidatedSymbols &Escaped, const CallEvent *Call, PointerEscapeKind Kind) const { // If we know that the call cannot close a file, there is nothing to do. if (Kind == PSK_DirectEscapeOnCall && guaranteedNotToCloseFile(*Call)) { return State; } for (InvalidatedSymbols::const_iterator I = Escaped.begin(), E = Escaped.end(); I != E; ++I) { SymbolRef Sym = *I; // The symbol escaped. Optimistically, assume that the corresponding file // handle will be closed somewhere else. State = State->remove(Sym); } return State; } void SimpleStreamChecker::initIdentifierInfo(ASTContext &Ctx) const { if (IIfopen) return; IIfopen = &Ctx.Idents.get("fopen"); IIfclose = &Ctx.Idents.get("fclose"); } void ento::registerSimpleStreamChecker(CheckerManager &mgr) { mgr.registerChecker(); } @