forked from OSchip/llvm-project
210 lines
6.8 KiB
C++
210 lines
6.8 KiB
C++
// MallocSizeofChecker.cpp - Check for dubious malloc arguments ---*- C++ -*-=//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// Reports inconsistencies between the casted type of the return value of a
|
|
// malloc/calloc/realloc call and the operand of any sizeof expressions
|
|
// contained within its argument(s).
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "ClangSACheckers.h"
|
|
#include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
|
|
#include "clang/StaticAnalyzer/Core/Checker.h"
|
|
#include "clang/StaticAnalyzer/Core/CheckerManager.h"
|
|
#include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
|
|
#include "clang/AST/StmtVisitor.h"
|
|
#include "clang/AST/TypeLoc.h"
|
|
#include "llvm/ADT/SmallString.h"
|
|
|
|
using namespace clang;
|
|
using namespace ento;
|
|
|
|
namespace {
|
|
|
|
typedef std::pair<const TypeSourceInfo *, const CallExpr *> TypeCallPair;
|
|
typedef llvm::PointerUnion<const Stmt *, const VarDecl *> ExprParent;
|
|
|
|
class CastedAllocFinder
|
|
: public ConstStmtVisitor<CastedAllocFinder, TypeCallPair> {
|
|
IdentifierInfo *II_malloc, *II_calloc, *II_realloc;
|
|
|
|
public:
|
|
struct CallRecord {
|
|
ExprParent CastedExprParent;
|
|
const Expr *CastedExpr;
|
|
const TypeSourceInfo *ExplicitCastType;
|
|
const CallExpr *AllocCall;
|
|
|
|
CallRecord(ExprParent CastedExprParent, const Expr *CastedExpr,
|
|
const TypeSourceInfo *ExplicitCastType,
|
|
const CallExpr *AllocCall)
|
|
: CastedExprParent(CastedExprParent), CastedExpr(CastedExpr),
|
|
ExplicitCastType(ExplicitCastType), AllocCall(AllocCall) {}
|
|
};
|
|
|
|
typedef std::vector<CallRecord> CallVec;
|
|
CallVec Calls;
|
|
|
|
CastedAllocFinder(ASTContext *Ctx) :
|
|
II_malloc(&Ctx->Idents.get("malloc")),
|
|
II_calloc(&Ctx->Idents.get("calloc")),
|
|
II_realloc(&Ctx->Idents.get("realloc")) {}
|
|
|
|
void VisitChild(ExprParent Parent, const Stmt *S) {
|
|
TypeCallPair AllocCall = Visit(S);
|
|
if (AllocCall.second && AllocCall.second != S)
|
|
Calls.push_back(CallRecord(Parent, cast<Expr>(S), AllocCall.first,
|
|
AllocCall.second));
|
|
}
|
|
|
|
void VisitChildren(const Stmt *S) {
|
|
for (Stmt::const_child_iterator I = S->child_begin(), E = S->child_end();
|
|
I!=E; ++I)
|
|
if (const Stmt *child = *I)
|
|
VisitChild(S, child);
|
|
}
|
|
|
|
TypeCallPair VisitCastExpr(const CastExpr *E) {
|
|
return Visit(E->getSubExpr());
|
|
}
|
|
|
|
TypeCallPair VisitExplicitCastExpr(const ExplicitCastExpr *E) {
|
|
return TypeCallPair(E->getTypeInfoAsWritten(),
|
|
Visit(E->getSubExpr()).second);
|
|
}
|
|
|
|
TypeCallPair VisitParenExpr(const ParenExpr *E) {
|
|
return Visit(E->getSubExpr());
|
|
}
|
|
|
|
TypeCallPair VisitStmt(const Stmt *S) {
|
|
VisitChildren(S);
|
|
return TypeCallPair();
|
|
}
|
|
|
|
TypeCallPair VisitCallExpr(const CallExpr *E) {
|
|
VisitChildren(E);
|
|
const FunctionDecl *FD = E->getDirectCallee();
|
|
if (FD) {
|
|
IdentifierInfo *II = FD->getIdentifier();
|
|
if (II == II_malloc || II == II_calloc || II == II_realloc)
|
|
return TypeCallPair((const TypeSourceInfo *)0, E);
|
|
}
|
|
return TypeCallPair();
|
|
}
|
|
|
|
TypeCallPair VisitDeclStmt(const DeclStmt *S) {
|
|
for (DeclStmt::const_decl_iterator I = S->decl_begin(), E = S->decl_end();
|
|
I!=E; ++I)
|
|
if (const VarDecl *VD = dyn_cast<VarDecl>(*I))
|
|
if (const Expr *Init = VD->getInit())
|
|
VisitChild(VD, Init);
|
|
return TypeCallPair();
|
|
}
|
|
};
|
|
|
|
class SizeofFinder : public ConstStmtVisitor<SizeofFinder> {
|
|
public:
|
|
std::vector<const UnaryExprOrTypeTraitExpr *> Sizeofs;
|
|
|
|
void VisitBinMul(const BinaryOperator *E) {
|
|
Visit(E->getLHS());
|
|
Visit(E->getRHS());
|
|
}
|
|
|
|
void VisitBinAdd(const BinaryOperator *E) {
|
|
Visit(E->getLHS());
|
|
Visit(E->getRHS());
|
|
}
|
|
|
|
void VisitImplicitCastExpr(const ImplicitCastExpr *E) {
|
|
return Visit(E->getSubExpr());
|
|
}
|
|
|
|
void VisitParenExpr(const ParenExpr *E) {
|
|
return Visit(E->getSubExpr());
|
|
}
|
|
|
|
void VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *E) {
|
|
if (E->getKind() != UETT_SizeOf)
|
|
return;
|
|
|
|
Sizeofs.push_back(E);
|
|
}
|
|
};
|
|
|
|
class MallocSizeofChecker : public Checker<check::ASTCodeBody> {
|
|
public:
|
|
void checkASTCodeBody(const Decl *D, AnalysisManager& mgr,
|
|
BugReporter &BR) const {
|
|
AnalysisDeclContext *ADC = mgr.getAnalysisDeclContext(D);
|
|
CastedAllocFinder Finder(&BR.getContext());
|
|
Finder.Visit(D->getBody());
|
|
for (CastedAllocFinder::CallVec::iterator i = Finder.Calls.begin(),
|
|
e = Finder.Calls.end(); i != e; ++i) {
|
|
QualType CastedType = i->CastedExpr->getType();
|
|
if (!CastedType->isPointerType())
|
|
continue;
|
|
QualType PointeeType = CastedType->getAs<PointerType>()->getPointeeType();
|
|
if (PointeeType->isVoidType())
|
|
continue;
|
|
|
|
for (CallExpr::const_arg_iterator ai = i->AllocCall->arg_begin(),
|
|
ae = i->AllocCall->arg_end(); ai != ae; ++ai) {
|
|
if (!(*ai)->getType()->isIntegerType())
|
|
continue;
|
|
|
|
SizeofFinder SFinder;
|
|
SFinder.Visit(*ai);
|
|
if (SFinder.Sizeofs.size() != 1)
|
|
continue;
|
|
|
|
QualType SizeofType = SFinder.Sizeofs[0]->getTypeOfArgument();
|
|
if (!BR.getContext().hasSameUnqualifiedType(PointeeType, SizeofType)) {
|
|
const TypeSourceInfo *TSI = 0;
|
|
if (i->CastedExprParent.is<const VarDecl *>()) {
|
|
TSI =
|
|
i->CastedExprParent.get<const VarDecl *>()->getTypeSourceInfo();
|
|
} else {
|
|
TSI = i->ExplicitCastType;
|
|
}
|
|
|
|
SmallString<64> buf;
|
|
llvm::raw_svector_ostream OS(buf);
|
|
|
|
OS << "Result of '"
|
|
<< i->AllocCall->getDirectCallee()->getIdentifier()->getName()
|
|
<< "' is converted to type '"
|
|
<< CastedType.getAsString() << "', whose pointee type '"
|
|
<< PointeeType.getAsString() << "' is incompatible with "
|
|
<< "sizeof operand type '" << SizeofType.getAsString() << "'";
|
|
llvm::SmallVector<SourceRange, 4> Ranges;
|
|
Ranges.push_back(i->AllocCall->getCallee()->getSourceRange());
|
|
Ranges.push_back(SFinder.Sizeofs[0]->getSourceRange());
|
|
if (TSI)
|
|
Ranges.push_back(TSI->getTypeLoc().getSourceRange());
|
|
|
|
PathDiagnosticLocation L =
|
|
PathDiagnosticLocation::createBegin(i->AllocCall->getCallee(),
|
|
BR.getSourceManager(), ADC);
|
|
|
|
BR.EmitBasicReport("allocator sizeof operand mismatch", OS.str(), L,
|
|
Ranges.data(), Ranges.size());
|
|
}
|
|
}
|
|
}
|
|
}
|
|
};
|
|
|
|
}
|
|
|
|
void ento::registerMallocSizeofChecker(CheckerManager &mgr) {
|
|
mgr.registerChecker<MallocSizeofChecker>();
|
|
}
|