1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
|
//== PutenvWithAutoChecker.cpp --------------------------------- -*- C++ -*--=//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines PutenvWithAutoChecker which finds calls of ``putenv``
// function with automatic variable as the argument.
// https://wiki.sei.cmu.edu/confluence/x/6NYxBQ
//
//===----------------------------------------------------------------------===//
#include "../AllocationState.h"
#include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
#include "clang/StaticAnalyzer/Core/Checker.h"
#include "clang/StaticAnalyzer/Core/CheckerManager.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/CallDescription.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
using namespace clang;
using namespace ento;
namespace {
class PutenvWithAutoChecker : public Checker<check::PostCall> {
private:
BugType BT{this, "'putenv' function should not be called with auto variables",
categories::SecurityError};
const CallDescription Putenv{"putenv", 1};
public:
void checkPostCall(const CallEvent &Call, CheckerContext &C) const;
};
} // namespace
void PutenvWithAutoChecker::checkPostCall(const CallEvent &Call,
CheckerContext &C) const {
if (!Putenv.matches(Call))
return;
SVal ArgV = Call.getArgSVal(0);
const Expr *ArgExpr = Call.getArgExpr(0);
const MemSpaceRegion *MSR = ArgV.getAsRegion()->getMemorySpace();
if (!isa<StackSpaceRegion>(MSR))
return;
StringRef ErrorMsg = "The 'putenv' function should not be called with "
"arguments that have automatic storage";
ExplodedNode *N = C.generateErrorNode();
auto Report = std::make_unique<PathSensitiveBugReport>(BT, ErrorMsg, N);
// Track the argument.
bugreporter::trackExpressionValue(Report->getErrorNode(), ArgExpr, *Report);
C.emitReport(std::move(Report));
}
void ento::registerPutenvWithAuto(CheckerManager &Mgr) {
Mgr.registerChecker<PutenvWithAutoChecker>();
}
bool ento::shouldRegisterPutenvWithAuto(const CheckerManager &) { return true; }
|
