diff options
Diffstat (limited to 'contrib/llvm/tools/clang/lib/Checker/StreamChecker.cpp')
| -rw-r--r-- | contrib/llvm/tools/clang/lib/Checker/StreamChecker.cpp | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/contrib/llvm/tools/clang/lib/Checker/StreamChecker.cpp b/contrib/llvm/tools/clang/lib/Checker/StreamChecker.cpp new file mode 100644 index 0000000..c527ca2 --- /dev/null +++ b/contrib/llvm/tools/clang/lib/Checker/StreamChecker.cpp @@ -0,0 +1,287 @@ +//===-- StreamChecker.cpp -----------------------------------------*- C++ -*--// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file defines checkers that model and check stream handling functions. +// +//===----------------------------------------------------------------------===// + +#include "GRExprEngineExperimentalChecks.h" +#include "clang/Checker/BugReporter/BugType.h" +#include "clang/Checker/PathSensitive/CheckerVisitor.h" +#include "clang/Checker/PathSensitive/GRState.h" +#include "clang/Checker/PathSensitive/GRStateTrait.h" +#include "clang/Checker/PathSensitive/SymbolManager.h" +#include "llvm/ADT/ImmutableMap.h" + +using namespace clang; + +namespace { + +class StreamChecker : public CheckerVisitor<StreamChecker> { + IdentifierInfo *II_fopen, *II_fread, *II_fwrite, + *II_fseek, *II_ftell, *II_rewind, *II_fgetpos, *II_fsetpos, + *II_clearerr, *II_feof, *II_ferror, *II_fileno; + BuiltinBug *BT_nullfp, *BT_illegalwhence; + +public: + StreamChecker() + : II_fopen(0), II_fread(0), II_fwrite(0), + II_fseek(0), II_ftell(0), II_rewind(0), II_fgetpos(0), II_fsetpos(0), + II_clearerr(0), II_feof(0), II_ferror(0), II_fileno(0), + BT_nullfp(0), BT_illegalwhence(0) {} + + static void *getTag() { + static int x; + return &x; + } + + virtual bool EvalCallExpr(CheckerContext &C, const CallExpr *CE); + +private: + void Fopen(CheckerContext &C, const CallExpr *CE); + void Fread(CheckerContext &C, const CallExpr *CE); + void Fwrite(CheckerContext &C, const CallExpr *CE); + void Fseek(CheckerContext &C, const CallExpr *CE); + void Ftell(CheckerContext &C, const CallExpr *CE); + void Rewind(CheckerContext &C, const CallExpr *CE); + void Fgetpos(CheckerContext &C, const CallExpr *CE); + void Fsetpos(CheckerContext &C, const CallExpr *CE); + void Clearerr(CheckerContext &C, const CallExpr *CE); + void Feof(CheckerContext &C, const CallExpr *CE); + void Ferror(CheckerContext &C, const CallExpr *CE); + void Fileno(CheckerContext &C, const CallExpr *CE); + + // Return true indicates the stream pointer is NULL. + const GRState *CheckNullStream(SVal SV, const GRState *state, + CheckerContext &C); +}; + +} // end anonymous namespace + +void clang::RegisterStreamChecker(GRExprEngine &Eng) { + Eng.registerCheck(new StreamChecker()); +} + +bool StreamChecker::EvalCallExpr(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + const Expr *Callee = CE->getCallee(); + SVal L = state->getSVal(Callee); + const FunctionDecl *FD = L.getAsFunctionDecl(); + if (!FD) + return false; + + ASTContext &Ctx = C.getASTContext(); + if (!II_fopen) + II_fopen = &Ctx.Idents.get("fopen"); + if (!II_fread) + II_fread = &Ctx.Idents.get("fread"); + if (!II_fwrite) + II_fwrite = &Ctx.Idents.get("fwrite"); + if (!II_fseek) + II_fseek = &Ctx.Idents.get("fseek"); + if (!II_ftell) + II_ftell = &Ctx.Idents.get("ftell"); + if (!II_rewind) + II_rewind = &Ctx.Idents.get("rewind"); + if (!II_fgetpos) + II_fgetpos = &Ctx.Idents.get("fgetpos"); + if (!II_fsetpos) + II_fsetpos = &Ctx.Idents.get("fsetpos"); + if (!II_clearerr) + II_clearerr = &Ctx.Idents.get("clearerr"); + if (!II_feof) + II_feof = &Ctx.Idents.get("feof"); + if (!II_ferror) + II_ferror = &Ctx.Idents.get("ferror"); + if (!II_fileno) + II_fileno = &Ctx.Idents.get("fileno"); + + if (FD->getIdentifier() == II_fopen) { + Fopen(C, CE); + return true; + } + if (FD->getIdentifier() == II_fread) { + Fread(C, CE); + return true; + } + if (FD->getIdentifier() == II_fwrite) { + Fwrite(C, CE); + return true; + } + if (FD->getIdentifier() == II_fseek) { + Fseek(C, CE); + return true; + } + if (FD->getIdentifier() == II_ftell) { + Ftell(C, CE); + return true; + } + if (FD->getIdentifier() == II_rewind) { + Rewind(C, CE); + return true; + } + if (FD->getIdentifier() == II_fgetpos) { + Fgetpos(C, CE); + return true; + } + if (FD->getIdentifier() == II_fsetpos) { + Fsetpos(C, CE); + return true; + } + if (FD->getIdentifier() == II_clearerr) { + Clearerr(C, CE); + return true; + } + if (FD->getIdentifier() == II_feof) { + Feof(C, CE); + return true; + } + if (FD->getIdentifier() == II_ferror) { + Ferror(C, CE); + return true; + } + if (FD->getIdentifier() == II_fileno) { + Fileno(C, CE); + return true; + } + + return false; +} + +void StreamChecker::Fopen(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + unsigned Count = C.getNodeBuilder().getCurrentBlockCount(); + ValueManager &ValMgr = C.getValueManager(); + DefinedSVal RetVal = cast<DefinedSVal>(ValMgr.getConjuredSymbolVal(0, CE, + Count)); + state = state->BindExpr(CE, RetVal); + + ConstraintManager &CM = C.getConstraintManager(); + // Bifurcate the state into two: one with a valid FILE* pointer, the other + // with a NULL. + const GRState *stateNotNull, *stateNull; + llvm::tie(stateNotNull, stateNull) = CM.AssumeDual(state, RetVal); + + C.addTransition(stateNotNull); + C.addTransition(stateNull); +} + +void StreamChecker::Fread(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + if (!CheckNullStream(state->getSVal(CE->getArg(3)), state, C)) + return; +} + +void StreamChecker::Fwrite(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + if (!CheckNullStream(state->getSVal(CE->getArg(3)), state, C)) + return; +} + +void StreamChecker::Fseek(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + if (!(state = CheckNullStream(state->getSVal(CE->getArg(0)), state, C))) + return; + // Check the legality of the 'whence' argument of 'fseek'. + SVal Whence = state->getSVal(CE->getArg(2)); + bool WhenceIsLegal = true; + const nonloc::ConcreteInt *CI = dyn_cast<nonloc::ConcreteInt>(&Whence); + if (!CI) + WhenceIsLegal = false; + + int64_t x = CI->getValue().getSExtValue(); + if (!(x == 0 || x == 1 || x == 2)) + WhenceIsLegal = false; + + if (!WhenceIsLegal) { + if (ExplodedNode *N = C.GenerateSink(state)) { + if (!BT_illegalwhence) + BT_illegalwhence = new BuiltinBug("Illegal whence argument", + "The whence argument to fseek() should be " + "SEEK_SET, SEEK_END, or SEEK_CUR."); + BugReport *R = new BugReport(*BT_illegalwhence, + BT_illegalwhence->getDescription(), N); + C.EmitReport(R); + } + return; + } + + C.addTransition(state); +} + +void StreamChecker::Ftell(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + if (!CheckNullStream(state->getSVal(CE->getArg(0)), state, C)) + return; +} + +void StreamChecker::Rewind(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + if (!CheckNullStream(state->getSVal(CE->getArg(0)), state, C)) + return; +} + +void StreamChecker::Fgetpos(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + if (!CheckNullStream(state->getSVal(CE->getArg(0)), state, C)) + return; +} + +void StreamChecker::Fsetpos(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + if (!CheckNullStream(state->getSVal(CE->getArg(0)), state, C)) + return; +} + +void StreamChecker::Clearerr(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + if (!CheckNullStream(state->getSVal(CE->getArg(0)), state, C)) + return; +} + +void StreamChecker::Feof(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + if (!CheckNullStream(state->getSVal(CE->getArg(0)), state, C)) + return; +} + +void StreamChecker::Ferror(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + if (!CheckNullStream(state->getSVal(CE->getArg(0)), state, C)) + return; +} + +void StreamChecker::Fileno(CheckerContext &C, const CallExpr *CE) { + const GRState *state = C.getState(); + if (!CheckNullStream(state->getSVal(CE->getArg(0)), state, C)) + return; +} + +const GRState *StreamChecker::CheckNullStream(SVal SV, const GRState *state, + CheckerContext &C) { + const DefinedSVal *DV = dyn_cast<DefinedSVal>(&SV); + if (!DV) + return 0; + + ConstraintManager &CM = C.getConstraintManager(); + const GRState *stateNotNull, *stateNull; + llvm::tie(stateNotNull, stateNull) = CM.AssumeDual(state, *DV); + + if (!stateNotNull && stateNull) { + if (ExplodedNode *N = C.GenerateSink(stateNull)) { + if (!BT_nullfp) + BT_nullfp = new BuiltinBug("NULL stream pointer", + "Stream pointer might be NULL."); + BugReport *R =new BugReport(*BT_nullfp, BT_nullfp->getDescription(), N); + C.EmitReport(R); + } + return 0; + } + return stateNotNull; +} |
