diff options
-rw-r--r-- | include/clang/Analysis/LocalCheckers.h | 2 | ||||
-rw-r--r-- | include/clang/Frontend/Analyses.def | 3 | ||||
-rw-r--r-- | lib/Analysis/CheckSizeofPointer.cpp | 58 | ||||
-rw-r--r-- | lib/Frontend/AnalysisConsumer.cpp | 5 |
4 files changed, 67 insertions, 1 deletions
diff --git a/include/clang/Analysis/LocalCheckers.h b/include/clang/Analysis/LocalCheckers.h index 1da15fbae6..cd2d6b3ec7 100644 --- a/include/clang/Analysis/LocalCheckers.h +++ b/include/clang/Analysis/LocalCheckers.h @@ -53,7 +53,7 @@ void RegisterAppleChecks(GRExprEngine& Eng, const Decl &D); void CheckSecuritySyntaxOnly(const Decl *D, BugReporter &BR); - +void CheckSizeofPointer(const Decl *D, BugReporter &BR); } // end namespace clang #endif diff --git a/include/clang/Frontend/Analyses.def b/include/clang/Frontend/Analyses.def index d5e408020a..7d55673a61 100644 --- a/include/clang/Frontend/Analyses.def +++ b/include/clang/Frontend/Analyses.def @@ -48,6 +48,9 @@ ANALYSIS(WarnObjCUnusedIvars, "warn-objc-unused-ivars", ANALYSIS(CheckerCFRef, "checker-cfref", "Run the [Core] Foundation reference count checker", Code) +ANALYSIS(WarnSizeofPointer, "warn-sizeof-pointer", + "Warn about unintended use of sizeof() on pointer expressions", Code) + ANALYSIS(InlineCall, "inline-call", "Experimental transfer function inling callees when its definition" " is available.", TranslationUnit) diff --git a/lib/Analysis/CheckSizeofPointer.cpp b/lib/Analysis/CheckSizeofPointer.cpp new file mode 100644 index 0000000000..c61f6f570a --- /dev/null +++ b/lib/Analysis/CheckSizeofPointer.cpp @@ -0,0 +1,58 @@ +//==- CheckSizeofPointer.cpp - Check for sizeof on pointers ------*- 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 a check for unintended use of sizeof() on pointer +// expressions. +// +//===----------------------------------------------------------------------===// + +#include "clang/Analysis/PathSensitive/BugReporter.h" +#include "clang/AST/StmtVisitor.h" +#include "clang/Analysis/LocalCheckers.h" +#include "llvm/Support/Compiler.h" + +using namespace clang; + +namespace { +class VISIBILITY_HIDDEN WalkAST : public StmtVisitor<WalkAST> { + BugReporter &BR; + +public: + WalkAST(BugReporter &br) : BR(br) {} + void VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E); + void VisitStmt(Stmt *S) { VisitChildren(S); } + void VisitChildren(Stmt *S); +}; +} + +void WalkAST::VisitChildren(Stmt *S) { + for (Stmt::child_iterator I = S->child_begin(), E = S->child_end(); I!=E; ++I) + if (Stmt *child = *I) + Visit(child); +} + +// CWE-467: Use of sizeof() on a Pointer Type +void WalkAST::VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E) { + if (!E->isSizeOf()) + return; + + QualType T = E->getTypeOfArgument(); + if (T->isPointerType()) { + SourceRange R = E->getArgumentExpr()->getSourceRange(); + BR.EmitBasicReport("Potential unintended use of sizeof() on pointer type", + "Logic", + "The code calls sizeof() on a malloced pointer type, which always returns the wordsize/8. This can produce an unexpected result if the programmer intended to determine how much memory has been allocated.", + E->getLocStart(), &R, 1); + } +} + +void clang::CheckSizeofPointer(const Decl *D, BugReporter &BR) { + WalkAST walker(BR); + walker.Visit(D->getBody()); +} diff --git a/lib/Frontend/AnalysisConsumer.cpp b/lib/Frontend/AnalysisConsumer.cpp index d2831fae56..abe04b02ab 100644 --- a/lib/Frontend/AnalysisConsumer.cpp +++ b/lib/Frontend/AnalysisConsumer.cpp @@ -412,6 +412,11 @@ static void ActionWarnObjCMethSigs(AnalysisManager& mgr, Decl *D) { CheckObjCInstMethSignature(cast<ObjCImplementationDecl>(D), BR); } +static void ActionWarnSizeofPointer(AnalysisManager &mgr, Decl *D) { + BugReporter BR(mgr); + CheckSizeofPointer(D, BR); +} + static void ActionInlineCall(AnalysisManager &mgr, Decl *D) { if (!D) return; |