Add a checker for CWE-466: Return of Pointer Value Outside of Expected Range.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@86252 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Analysis/PathSensitive/Checker.h b/include/clang/Analysis/PathSensitive/Checker.h
index 2564a73..a87d72b 100644
--- a/include/clang/Analysis/PathSensitive/Checker.h
+++ b/include/clang/Analysis/PathSensitive/Checker.h
@@ -64,6 +64,11 @@
ConstraintManager &getConstraintManager() {
return Eng.getConstraintManager();
}
+
+ StoreManager &getStoreManager() {
+ return Eng.getStoreManager();
+ }
+
ExplodedNodeSet &getNodeSet() { return Dst; }
GRStmtNodeBuilder &getNodeBuilder() { return B; }
ExplodedNode *&getPredecessor() { return Pred; }
diff --git a/lib/Analysis/CMakeLists.txt b/lib/Analysis/CMakeLists.txt
index 111f273..1871b54 100644
--- a/lib/Analysis/CMakeLists.txt
+++ b/lib/Analysis/CMakeLists.txt
@@ -36,6 +36,7 @@
PathDiagnostic.cpp
RangeConstraintManager.cpp
RegionStore.cpp
+ ReturnPointerRangeChecker.cpp
ReturnStackAddressChecker.cpp
ReturnUndefChecker.cpp
SVals.cpp
diff --git a/lib/Analysis/GRExprEngineInternalChecks.cpp b/lib/Analysis/GRExprEngineInternalChecks.cpp
index 4bb5d22..b18e58d 100644
--- a/lib/Analysis/GRExprEngineInternalChecks.cpp
+++ b/lib/Analysis/GRExprEngineInternalChecks.cpp
@@ -405,6 +405,7 @@
// object.
RegisterReturnStackAddressChecker(*this);
RegisterReturnUndefChecker(*this);
+ RegisterReturnPointerRangeChecker(*this);
registerCheck(new AttrNonNullChecker());
registerCheck(new UndefinedArgChecker());
registerCheck(new UndefinedAssignmentChecker());
diff --git a/lib/Analysis/GRExprEngineInternalChecks.h b/lib/Analysis/GRExprEngineInternalChecks.h
index 622b5ab..b4a00d2 100644
--- a/lib/Analysis/GRExprEngineInternalChecks.h
+++ b/lib/Analysis/GRExprEngineInternalChecks.h
@@ -21,6 +21,7 @@
void RegisterReturnStackAddressChecker(GRExprEngine &Eng);
void RegisterReturnUndefChecker(GRExprEngine &Eng);
+void RegisterReturnPointerRangeChecker(GRExprEngine &Eng);
} // end clang namespace
#endif
diff --git a/lib/Analysis/ReturnPointerRangeChecker.cpp b/lib/Analysis/ReturnPointerRangeChecker.cpp
new file mode 100644
index 0000000..4ca7271
--- /dev/null
+++ b/lib/Analysis/ReturnPointerRangeChecker.cpp
@@ -0,0 +1,86 @@
+//== ReturnPointerRangeChecker.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 ReturnPointerRangeChecker, which is a path-sensitive check
+// which looks for an out-of-bound pointer being returned to callers.
+//
+//===----------------------------------------------------------------------===//
+
+#include "GRExprEngineInternalChecks.h"
+#include "clang/Analysis/PathSensitive/GRExprEngine.h"
+#include "clang/Analysis/PathSensitive/BugReporter.h"
+#include "clang/Analysis/PathSensitive/CheckerVisitor.h"
+
+using namespace clang;
+
+namespace {
+class VISIBILITY_HIDDEN ReturnPointerRangeChecker :
+ public CheckerVisitor<ReturnPointerRangeChecker> {
+ BuiltinBug *BT;
+public:
+ ReturnPointerRangeChecker() : BT(0) {}
+ static void *getTag();
+ void PreVisitReturnStmt(CheckerContext &C, const ReturnStmt *RS);
+};
+}
+
+void clang::RegisterReturnPointerRangeChecker(GRExprEngine &Eng) {
+ Eng.registerCheck(new ReturnPointerRangeChecker());
+}
+
+void *ReturnPointerRangeChecker::getTag() {
+ static int x = 0; return &x;
+}
+
+void ReturnPointerRangeChecker::PreVisitReturnStmt(CheckerContext &C,
+ const ReturnStmt *RS) {
+ const GRState *state = C.getState();
+
+ const Expr *RetE = RS->getRetValue();
+ if (!RetE)
+ return;
+
+ SVal V = state->getSVal(RetE);
+ const MemRegion *R = V.getAsRegion();
+
+ const ElementRegion *ER = dyn_cast_or_null<ElementRegion>(R);
+ if (!ER)
+ return;
+
+ DefinedOrUnknownSVal &Idx = cast<DefinedOrUnknownSVal>(ER->getIndex());
+
+ // Zero index is always in bound, this also passes ElementRegions created for
+ // pointer casts.
+ if (Idx.isZeroConstant())
+ return;
+
+ SVal NumVal = C.getStoreManager().getSizeInElements(state,
+ ER->getSuperRegion());
+ DefinedOrUnknownSVal &NumElements = cast<DefinedOrUnknownSVal>(NumVal);
+
+ const GRState *StInBound = state->AssumeInBound(Idx, NumElements, true);
+ const GRState *StOutBound = state->AssumeInBound(Idx, NumElements, false);
+ if (StOutBound && !StInBound) {
+ ExplodedNode *N = C.GenerateNode(RS, StOutBound, true);
+
+ if (!N)
+ return;
+
+ if (!BT)
+ BT = new BuiltinBug("Return of Pointer Value Outside of Expected Range");
+
+ // Generate a report for this bug.
+ RangedBugReport *report =
+ new RangedBugReport(*BT, BT->getDescription().c_str(), N);
+
+ report->addRange(RS->getSourceRange());
+
+ C.EmitReport(report);
+ }
+}
diff --git a/test/Analysis/region-only-test.c b/test/Analysis/region-only-test.c
index 8908adb..b1e70a9 100644
--- a/test/Analysis/region-only-test.c
+++ b/test/Analysis/region-only-test.c
@@ -11,3 +11,10 @@
if (p[0] == 1)
(void)*x; // no-warning
}
+
+int a[10];
+
+int *f0() {
+ int *p = a+10;
+ return p; // expected-warning{{Return of Pointer Value Outside of Expected Range}}
+}