Add 'bughuntingchecks'

This commit is contained in:
Daniel Marjamäki 2020-06-19 13:16:48 +02:00
parent cbe038e694
commit d0ac583b97
6 changed files with 457 additions and 380 deletions

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@ -158,6 +158,7 @@ MAN_SOURCE=man/cppcheck.1.xml
LIBOBJ = $(libcppdir)/analyzerinfo.o \
$(libcppdir)/astutils.o \
$(libcppdir)/bughuntingchecks.o \
$(libcppdir)/check.o \
$(libcppdir)/check64bit.o \
$(libcppdir)/checkassert.o \
@ -407,6 +408,9 @@ $(libcppdir)/analyzerinfo.o: lib/analyzerinfo.cpp externals/tinyxml/tinyxml2.h l
$(libcppdir)/astutils.o: lib/astutils.cpp lib/astutils.h lib/config.h lib/errortypes.h lib/importproject.h lib/library.h lib/mathlib.h lib/platform.h lib/settings.h lib/standards.h lib/suppressions.h lib/symboldatabase.h lib/templatesimplifier.h lib/timer.h lib/token.h lib/utils.h lib/valueflow.h
$(CXX) ${INCLUDE_FOR_LIB} $(CPPFLAGS) $(CPPFILESDIR) $(CXXFLAGS) $(UNDEF_STRICT_ANSI) -c -o $(libcppdir)/astutils.o $(libcppdir)/astutils.cpp
$(libcppdir)/bughuntingchecks.o: lib/bughuntingchecks.cpp lib/astutils.h lib/bughuntingchecks.h lib/config.h lib/errorlogger.h lib/errortypes.h lib/exprengine.h lib/importproject.h lib/library.h lib/mathlib.h lib/platform.h lib/settings.h lib/standards.h lib/suppressions.h lib/symboldatabase.h lib/templatesimplifier.h lib/timer.h lib/token.h lib/utils.h lib/valueflow.h
$(CXX) ${INCLUDE_FOR_LIB} $(CPPFLAGS) $(CPPFILESDIR) $(CXXFLAGS) $(UNDEF_STRICT_ANSI) -c -o $(libcppdir)/bughuntingchecks.o $(libcppdir)/bughuntingchecks.cpp
$(libcppdir)/check.o: lib/check.cpp lib/check.h lib/config.h lib/errorlogger.h lib/errortypes.h lib/importproject.h lib/library.h lib/mathlib.h lib/platform.h lib/settings.h lib/standards.h lib/suppressions.h lib/templatesimplifier.h lib/timer.h lib/token.h lib/tokenize.h lib/tokenlist.h lib/utils.h lib/valueflow.h
$(CXX) ${INCLUDE_FOR_LIB} $(CPPFLAGS) $(CPPFILESDIR) $(CXXFLAGS) $(UNDEF_STRICT_ANSI) -c -o $(libcppdir)/check.o $(libcppdir)/check.cpp
@ -500,7 +504,7 @@ $(libcppdir)/errorlogger.o: lib/errorlogger.cpp externals/tinyxml/tinyxml2.h lib
$(libcppdir)/errortypes.o: lib/errortypes.cpp lib/config.h lib/errortypes.h
$(CXX) ${INCLUDE_FOR_LIB} $(CPPFLAGS) $(CPPFILESDIR) $(CXXFLAGS) $(UNDEF_STRICT_ANSI) -c -o $(libcppdir)/errortypes.o $(libcppdir)/errortypes.cpp
$(libcppdir)/exprengine.o: lib/exprengine.cpp lib/astutils.h lib/config.h lib/errorlogger.h lib/errortypes.h lib/exprengine.h lib/importproject.h lib/library.h lib/mathlib.h lib/platform.h lib/settings.h lib/standards.h lib/suppressions.h lib/symboldatabase.h lib/templatesimplifier.h lib/timer.h lib/token.h lib/tokenize.h lib/tokenlist.h lib/utils.h lib/valueflow.h
$(libcppdir)/exprengine.o: lib/exprengine.cpp lib/astutils.h lib/bughuntingchecks.h lib/config.h lib/errorlogger.h lib/errortypes.h lib/exprengine.h lib/importproject.h lib/library.h lib/mathlib.h lib/platform.h lib/settings.h lib/standards.h lib/suppressions.h lib/symboldatabase.h lib/templatesimplifier.h lib/timer.h lib/token.h lib/tokenize.h lib/tokenlist.h lib/utils.h lib/valueflow.h
$(CXX) ${INCLUDE_FOR_LIB} $(CPPFLAGS) $(CPPFILESDIR) $(CXXFLAGS) $(UNDEF_STRICT_ANSI) -c -o $(libcppdir)/exprengine.o $(libcppdir)/exprengine.cpp
$(libcppdir)/forwardanalyzer.o: lib/forwardanalyzer.cpp lib/astutils.h lib/config.h lib/errortypes.h lib/forwardanalyzer.h lib/importproject.h lib/library.h lib/mathlib.h lib/platform.h lib/settings.h lib/standards.h lib/suppressions.h lib/symboldatabase.h lib/templatesimplifier.h lib/timer.h lib/token.h lib/utils.h lib/valueflow.h lib/valueptr.h

415
lib/bughuntingchecks.cpp Normal file
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@ -0,0 +1,415 @@
/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2020 Cppcheck team.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "bughuntingchecks.h"
#include "astutils.h"
#include "errorlogger.h"
#include "settings.h"
#include "symboldatabase.h"
#include "token.h"
#include <cstring>
static float getKnownFloatValue(const Token *tok, float def)
{
for (const auto &value: tok->values()) {
if (value.isKnown() && value.valueType == ValueFlow::Value::ValueType::FLOAT)
return value.floatValue;
}
return def;
}
static void bufferOverflow(const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase)
{
if (!Token::simpleMatch(tok->astParent(), ","))
return;
if (!tok->valueType() || tok->valueType()->pointer != 1 || tok->valueType()->type != ::ValueType::Type::CHAR)
return;
int argnr = (tok == tok->astParent()->astOperand1()) ? 0 : 1;
const Token *ftok = tok->astParent();
while (Token::simpleMatch(ftok, ",")) {
++argnr;
ftok = ftok->astParent();
}
ftok = ftok ? ftok->previous() : nullptr;
if (!Token::Match(ftok, "%name% ("))
return;
int overflowArgument = 0;
if (const Library::Function *func = dataBase->settings->library.getFunction(ftok)) {
for (auto argNrChecks: func->argumentChecks) {
int nr = argNrChecks.first;
const Library::ArgumentChecks &checks = argNrChecks.second;
for (const Library::ArgumentChecks::MinSize &minsize: checks.minsizes) {
if (minsize.type == Library::ArgumentChecks::MinSize::STRLEN && minsize.arg == argnr)
overflowArgument = nr;
}
}
}
if (!overflowArgument)
return;
const bool bailout = (value.type == ExprEngine::ValueType::BailoutValue);
dataBase->reportError(tok,
Severity::SeverityType::error,
"bughuntingBufferOverflow",
"Buffer read/write, when calling '" + ftok->str() + "' it cannot be determined that " + std::to_string(overflowArgument) + getOrdinalText(overflowArgument) + " argument is not overflowed",
CWE(120),
false,
bailout);
}
static void divByZero(const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase)
{
if (!tok->astParent() || !std::strchr("/%", tok->astParent()->str()[0]))
return;
if (tok->hasKnownIntValue() && tok->getKnownIntValue() != 0)
return;
if (tok->isImpossibleIntValue(0))
return;
if (value.isUninit())
return;
float f = getKnownFloatValue(tok, 0.0f);
if (f > 0.0f || f < 0.0f)
return;
if (value.type == ExprEngine::ValueType::BailoutValue) {
if (Token::simpleMatch(tok->previous(), "sizeof ("))
return;
}
if (tok->astParent()->astOperand2() == tok && value.isEqual(dataBase, 0)) {
const char * const id = (tok->valueType() && tok->valueType()->isFloat()) ? "bughuntingDivByZeroFloat" : "bughuntingDivByZero";
const bool bailout = (value.type == ExprEngine::ValueType::BailoutValue);
dataBase->reportError(dataBase->settings->clang ? tok : tok->astParent(),
Severity::SeverityType::error,
id,
"There is division, cannot determine that there can't be a division by zero.",
CWE(369),
false,
bailout);
}
}
#ifdef BUG_HUNTING_INTEGEROVERFLOW
static void integerOverflow(const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase)
{
if (!tok->isArithmeticalOp() || !tok->valueType() || !tok->valueType()->isIntegral() || tok->valueType()->pointer > 0)
return;
const ExprEngine::BinOpResult *b = dynamic_cast<const ExprEngine::BinOpResult *>(&value);
if (!b)
return;
int bits = getIntBitsFromValueType(tok->valueType(), *dataBase->settings);
if (bits == 0 || bits >= 60)
return;
std::string errorMessage;
if (tok->valueType()->sign == ::ValueType::Sign::SIGNED) {
MathLib::bigint v = 1LL << (bits - 1);
if (b->isGreaterThan(dataBase, v-1))
errorMessage = "greater than " + std::to_string(v - 1);
if (b->isLessThan(dataBase, -v)) {
if (!errorMessage.empty())
errorMessage += " or ";
errorMessage += "less than " + std::to_string(-v);
}
} else {
MathLib::bigint maxValue = (1LL << bits) - 1;
if (b->isGreaterThan(dataBase, maxValue))
errorMessage = "greater than " + std::to_string(maxValue);
if (b->isLessThan(dataBase, 0)) {
if (!errorMessage.empty())
errorMessage += " or ";
errorMessage += "less than 0";
}
}
if (errorMessage.empty())
return;
errorMessage = "There is integer arithmetic, cannot determine that there can't be overflow (if result is " + errorMessage + ").";
if (tok->valueType()->sign == ::ValueType::Sign::UNSIGNED)
errorMessage += " Note that unsigned integer overflow is defined and will wrap around.";
dataBase->reportError(tok, Severity::SeverityType::error, "bughuntingIntegerOverflow", errorMessage, false, value.type == ExprEngine::ValueType::BailoutValue);
}
#endif
static void uninit(const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase)
{
if (!tok->astParent())
return;
std::string uninitStructMember;
if (const auto* structValue = dynamic_cast<const ExprEngine::StructValue*>(&value)) {
uninitStructMember = structValue->getUninitStructMember();
// uninitialized struct member => is there data copy of struct..
if (!uninitStructMember.empty()) {
if (!Token::Match(tok->astParent(), "[=,(]"))
return;
}
}
if (!value.isUninit() && uninitStructMember.empty())
return;
// lhs in assignment
if (tok->astParent()->str() == "=" && tok == tok->astParent()->astOperand1())
return;
// Avoid FP when there is bailout..
if (value.type == ExprEngine::ValueType::BailoutValue) {
if (tok->hasKnownValue())
return;
if (tok->function())
return;
if (Token::Match(tok, "<<|>>|,"))
// Only warn about the operands
return;
// lhs for scope operator
if (Token::Match(tok, "%name% ::"))
return;
if (tok->astParent()->str() == "::" && tok == tok->astParent()->astOperand1())
return;
if (tok->str() == "(")
// cast: result is not uninitialized if expression is initialized
// function: does not return a uninitialized value
return;
// Containers are not uninitialized
std::vector<const Token *> tokens{tok, tok->astOperand1(), tok->astOperand2()};
if (Token::Match(tok->previous(), ". %name%"))
tokens.push_back(tok->previous()->astOperand1());
for (const Token *t: tokens) {
if (t && t->valueType() && t->valueType()->pointer == 0 && t->valueType()->container)
return;
}
const Variable *var = tok->variable();
if (var && !var->isPointer()) {
if (!var->isLocal() || var->isStatic())
return;
}
if (var && (Token::Match(var->nameToken(), "%name% =") || Token::Match(var->nameToken(), "%varid% ; %varid% =", var->declarationId())))
return;
if (var && var->nameToken() == tok)
return;
}
// Uninitialized function argument
if (Token::Match(tok->astParent(), "[,(]")) {
const Token *parent = tok->astParent();
int count = 0;
if (Token::simpleMatch(parent, ",")) {
if (tok == parent->astOperand2())
++count;
while (Token::simpleMatch(parent, ",")) {
count++;
parent = parent->astParent();
}
}
if (Token::simpleMatch(parent, "(") && parent->astOperand1() != tok) {
if (parent->astOperand1()->function()) {
const Variable *argvar = parent->astOperand1()->function()->getArgumentVar(count);
if (argvar && argvar->isReference() && !argvar->isConst())
return;
}
}
}
// Avoid FP for array declaration
const Token *parent = tok->astParent();
while (parent && parent->str() == "[")
parent = parent->astParent();
if (!parent)
return;
if (!uninitStructMember.empty()) {
dataBase->reportError(tok,
Severity::SeverityType::error,
"bughuntingUninitStructMember",
"Cannot determine that '" + tok->expressionString() + "." + uninitStructMember + "' is initialized",
CWE_USE_OF_UNINITIALIZED_VARIABLE,
false,
value.type == ExprEngine::ValueType::BailoutValue);
return;
}
dataBase->reportError(tok,
Severity::SeverityType::error,
"bughuntingUninit",
"Cannot determine that '" + tok->expressionString() + "' is initialized",
CWE_USE_OF_UNINITIALIZED_VARIABLE,
false,
value.type == ExprEngine::ValueType::BailoutValue);
}
static void checkFunctionCall(const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase)
{
if (!Token::Match(tok->astParent(), "[(,]"))
return;
const Token *parent = tok->astParent();
while (Token::simpleMatch(parent, ","))
parent = parent->astParent();
if (!parent || parent->str() != "(")
return;
int num = 0;
for (const Token *argTok: getArguments(parent->astOperand1())) {
--num;
if (argTok == tok) {
num = -num;
break;
}
}
if (num <= 0)
return;
if (parent->astOperand1()->function()) {
const Variable *arg = parent->astOperand1()->function()->getArgumentVar(num - 1);
if (arg && arg->nameToken()) {
std::string bad;
MathLib::bigint low;
if (arg->nameToken()->getCppcheckAttribute(TokenImpl::CppcheckAttributes::Type::LOW, &low)) {
if (!(tok->hasKnownIntValue() && tok->getKnownIntValue() >= low) && value.isLessThan(dataBase, low))
bad = "__cppcheck_low__(" + std::to_string(low) + ")";
}
MathLib::bigint high;
if (arg->nameToken()->getCppcheckAttribute(TokenImpl::CppcheckAttributes::Type::HIGH, &high)) {
if (!(tok->hasKnownIntValue() && tok->getKnownIntValue() <= high) && value.isGreaterThan(dataBase, high))
bad = "__cppcheck_high__(" + std::to_string(high) + ")";
}
if (!bad.empty()) {
dataBase->reportError(tok,
Severity::SeverityType::error,
"bughuntingInvalidArgValue",
"There is function call, cannot determine that " + std::to_string(num) + getOrdinalText(num) + " argument value meets the attribute " + bad,
CWE(0),
false);
return;
}
}
}
// Check invalid function argument values..
for (const Library::InvalidArgValue &invalidArgValue : Library::getInvalidArgValues(dataBase->settings->library.validarg(parent->astOperand1(), num))) {
bool err = false;
std::string bad;
switch (invalidArgValue.type) {
case Library::InvalidArgValue::eq:
if (!tok->hasKnownIntValue() || tok->getKnownIntValue() == MathLib::toLongNumber(invalidArgValue.op1))
err = value.isEqual(dataBase, MathLib::toLongNumber(invalidArgValue.op1));
bad = "equals " + invalidArgValue.op1;
break;
case Library::InvalidArgValue::le:
if (!tok->hasKnownIntValue() || tok->getKnownIntValue() <= MathLib::toLongNumber(invalidArgValue.op1))
err = value.isLessThan(dataBase, MathLib::toLongNumber(invalidArgValue.op1) + 1);
bad = "less equal " + invalidArgValue.op1;
break;
case Library::InvalidArgValue::lt:
if (!tok->hasKnownIntValue() || tok->getKnownIntValue() < MathLib::toLongNumber(invalidArgValue.op1))
err = value.isLessThan(dataBase, MathLib::toLongNumber(invalidArgValue.op1));
bad = "less than " + invalidArgValue.op1;
break;
case Library::InvalidArgValue::ge:
if (!tok->hasKnownIntValue() || tok->getKnownIntValue() >= MathLib::toLongNumber(invalidArgValue.op1))
err = value.isGreaterThan(dataBase, MathLib::toLongNumber(invalidArgValue.op1) - 1);
bad = "greater equal " + invalidArgValue.op1;
break;
case Library::InvalidArgValue::gt:
if (!tok->hasKnownIntValue() || tok->getKnownIntValue() > MathLib::toLongNumber(invalidArgValue.op1))
err = value.isGreaterThan(dataBase, MathLib::toLongNumber(invalidArgValue.op1));
bad = "greater than " + invalidArgValue.op1;
break;
case Library::InvalidArgValue::range:
// TODO
err = value.isEqual(dataBase, MathLib::toLongNumber(invalidArgValue.op1));
err |= value.isEqual(dataBase, MathLib::toLongNumber(invalidArgValue.op2));
bad = "range " + invalidArgValue.op1 + "-" + invalidArgValue.op2;
break;
}
if (err) {
dataBase->reportError(tok, Severity::SeverityType::error, "bughuntingInvalidArgValue", "There is function call, cannot determine that " + std::to_string(num) + getOrdinalText(num) + " argument value is valid. Bad value: " + bad, CWE(0), false);
break;
}
}
// Uninitialized function argument..
if (dataBase->settings->library.isuninitargbad(parent->astOperand1(), num) && dataBase->settings->library.isnullargbad(parent->astOperand1(), num) && value.type == ExprEngine::ValueType::ArrayValue) {
const ExprEngine::ArrayValue &arrayValue = static_cast<const ExprEngine::ArrayValue &>(value);
auto index0 = std::make_shared<ExprEngine::IntRange>("0", 0, 0);
for (const auto &v: arrayValue.read(index0)) {
if (v.second->isUninit()) {
dataBase->reportError(tok, Severity::SeverityType::error, "bughuntingUninitArg", "There is function call, cannot determine that " + std::to_string(num) + getOrdinalText(num) + " argument is initialized.", CWE_USE_OF_UNINITIALIZED_VARIABLE, false);
break;
}
}
}
}
static void checkAssignment(const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase)
{
if (!Token::simpleMatch(tok->astParent(), "="))
return;
const Token *lhs = tok->astParent()->astOperand1();
while (Token::simpleMatch(lhs, "."))
lhs = lhs->astOperand2();
if (!lhs || !lhs->variable() || !lhs->variable()->nameToken())
return;
const Token *vartok = lhs->variable()->nameToken();
MathLib::bigint low;
if (vartok->getCppcheckAttribute(TokenImpl::CppcheckAttributes::Type::LOW, &low)) {
if (value.isLessThan(dataBase, low))
dataBase->reportError(tok, Severity::SeverityType::error, "bughuntingAssign", "There is assignment, cannot determine that value is greater or equal with " + std::to_string(low), CWE_INCORRECT_CALCULATION, false);
}
MathLib::bigint high;
if (vartok->getCppcheckAttribute(TokenImpl::CppcheckAttributes::Type::HIGH, &high)) {
if (value.isGreaterThan(dataBase, high))
dataBase->reportError(tok, Severity::SeverityType::error, "bughuntingAssign", "There is assignment, cannot determine that value is lower or equal with " + std::to_string(high), CWE_INCORRECT_CALCULATION, false);
}
}
void addBughuntingChecks(std::vector<ExprEngine::Callback> *callbacks)
{
callbacks->push_back(bufferOverflow);
callbacks->push_back(divByZero);
callbacks->push_back(checkFunctionCall);
callbacks->push_back(checkAssignment);
#ifdef BUG_HUNTING_INTEGEROVERFLOW
callbacks->push_back(integerOverflow);
#endif
callbacks->push_back(uninit);
}

31
lib/bughuntingchecks.h Normal file
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@ -0,0 +1,31 @@
/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2020 Cppcheck team.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
//---------------------------------------------------------------------------
#ifndef bughuntingchecksH
#define bughuntingchecksH
//---------------------------------------------------------------------------
#include "exprengine.h"
#include <vector>
void addBughuntingChecks(std::vector<ExprEngine::Callback> *callbacks);
//---------------------------------------------------------------------------
#endif // bughuntingchecksH

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@ -132,13 +132,12 @@
#include "exprengine.h"
#include "astutils.h"
#include "bughuntingchecks.h"
#include "errorlogger.h"
#include "settings.h"
#include "symboldatabase.h"
#include "tokenize.h"
#include <cstdlib>
#include <cstring>
#include <limits>
#include <memory>
#include <iostream>
@ -2272,385 +2271,11 @@ void ExprEngine::executeFunction(const Scope *functionScope, ErrorLogger *errorL
}
}
static float getKnownFloatValue(const Token *tok, float def)
{
for (const auto &value: tok->values()) {
if (value.isKnown() && value.valueType == ValueFlow::Value::ValueType::FLOAT)
return value.floatValue;
}
return def;
}
void ExprEngine::runChecks(ErrorLogger *errorLogger, const Tokenizer *tokenizer, const Settings *settings)
{
std::function<void(const Token *, const ExprEngine::Value &, ExprEngine::DataBase *)> bufferOverflow = [=](const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase) {
if (!Token::simpleMatch(tok->astParent(), ","))
return;
if (!tok->valueType() || tok->valueType()->pointer != 1 || tok->valueType()->type != ::ValueType::Type::CHAR)
return;
int argnr = (tok == tok->astParent()->astOperand1()) ? 0 : 1;
const Token *ftok = tok->astParent();
while (Token::simpleMatch(ftok, ",")) {
++argnr;
ftok = ftok->astParent();
}
ftok = ftok ? ftok->previous() : nullptr;
if (!Token::Match(ftok, "%name% ("))
return;
int overflowArgument = 0;
if (const Library::Function *func = settings->library.getFunction(ftok)) {
for (auto argNrChecks: func->argumentChecks) {
int nr = argNrChecks.first;
const Library::ArgumentChecks &checks = argNrChecks.second;
for (const Library::ArgumentChecks::MinSize &minsize: checks.minsizes) {
if (minsize.type == Library::ArgumentChecks::MinSize::STRLEN && minsize.arg == argnr)
overflowArgument = nr;
}
}
}
if (!overflowArgument)
return;
const bool bailout = (value.type == ExprEngine::ValueType::BailoutValue);
dataBase->reportError(tok,
Severity::SeverityType::error,
"bughuntingBufferOverflow",
"Buffer read/write, when calling '" + ftok->str() + "' it cannot be determined that " + std::to_string(overflowArgument) + getOrdinalText(overflowArgument) + " argument is not overflowed",
CWE(120),
false,
bailout);
};
std::function<void(const Token *, const ExprEngine::Value &, ExprEngine::DataBase *)> divByZero = [=](const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase) {
if (!tok->astParent() || !std::strchr("/%", tok->astParent()->str()[0]))
return;
if (tok->hasKnownIntValue() && tok->getKnownIntValue() != 0)
return;
if (tok->isImpossibleIntValue(0))
return;
if (value.isUninit())
return;
float f = getKnownFloatValue(tok, 0.0f);
if (f > 0.0f || f < 0.0f)
return;
if (value.type == ExprEngine::ValueType::BailoutValue) {
if (Token::simpleMatch(tok->previous(), "sizeof ("))
return;
}
if (tok->astParent()->astOperand2() == tok && value.isEqual(dataBase, 0)) {
const char * const id = (tok->valueType() && tok->valueType()->isFloat()) ? "bughuntingDivByZeroFloat" : "bughuntingDivByZero";
const bool bailout = (value.type == ExprEngine::ValueType::BailoutValue);
dataBase->reportError(settings->clang ? tok : tok->astParent(),
Severity::SeverityType::error,
id,
"There is division, cannot determine that there can't be a division by zero.",
CWE(369),
false,
bailout);
}
};
#ifdef BUG_HUNTING_INTEGEROVERFLOW
std::function<void(const Token *, const ExprEngine::Value &, ExprEngine::DataBase *)> integerOverflow = [&](const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase) {
if (!tok->isArithmeticalOp() || !tok->valueType() || !tok->valueType()->isIntegral() || tok->valueType()->pointer > 0)
return;
const ExprEngine::BinOpResult *b = dynamic_cast<const ExprEngine::BinOpResult *>(&value);
if (!b)
return;
int bits = getIntBitsFromValueType(tok->valueType(), *settings);
if (bits == 0 || bits >= 60)
return;
std::string errorMessage;
if (tok->valueType()->sign == ::ValueType::Sign::SIGNED) {
MathLib::bigint v = 1LL << (bits - 1);
if (b->isGreaterThan(dataBase, v-1))
errorMessage = "greater than " + std::to_string(v - 1);
if (b->isLessThan(dataBase, -v)) {
if (!errorMessage.empty())
errorMessage += " or ";
errorMessage += "less than " + std::to_string(-v);
}
} else {
MathLib::bigint maxValue = (1LL << bits) - 1;
if (b->isGreaterThan(dataBase, maxValue))
errorMessage = "greater than " + std::to_string(maxValue);
if (b->isLessThan(dataBase, 0)) {
if (!errorMessage.empty())
errorMessage += " or ";
errorMessage += "less than 0";
}
}
if (errorMessage.empty())
return;
errorMessage = "There is integer arithmetic, cannot determine that there can't be overflow (if result is " + errorMessage + ").";
if (tok->valueType()->sign == ::ValueType::Sign::UNSIGNED)
errorMessage += " Note that unsigned integer overflow is defined and will wrap around.";
dataBase->reportError(tok, Severity::SeverityType::error, "bughuntingIntegerOverflow", errorMessage, false, value.type == ExprEngine::ValueType::BailoutValue);
};
#endif
std::function<void(const Token *, const ExprEngine::Value &, ExprEngine::DataBase *)> uninit = [=](const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase) {
if (!tok->astParent())
return;
std::string uninitStructMember;
if (const auto* structValue = dynamic_cast<const ExprEngine::StructValue*>(&value)) {
uninitStructMember = structValue->getUninitStructMember();
// uninitialized struct member => is there data copy of struct..
if (!uninitStructMember.empty()) {
if (!Token::Match(tok->astParent(), "[=,(]"))
return;
}
}
if (!value.isUninit() && uninitStructMember.empty())
return;
// lhs in assignment
if (tok->astParent()->str() == "=" && tok == tok->astParent()->astOperand1())
return;
// Avoid FP when there is bailout..
if (value.type == ExprEngine::ValueType::BailoutValue) {
if (tok->hasKnownValue())
return;
if (tok->function())
return;
if (Token::Match(tok, "<<|>>|,"))
// Only warn about the operands
return;
// lhs for scope operator
if (Token::Match(tok, "%name% ::"))
return;
if (tok->astParent()->str() == "::" && tok == tok->astParent()->astOperand1())
return;
if (tok->str() == "(")
// cast: result is not uninitialized if expression is initialized
// function: does not return a uninitialized value
return;
// Containers are not uninitialized
std::vector<const Token *> tokens{tok, tok->astOperand1(), tok->astOperand2()};
if (Token::Match(tok->previous(), ". %name%"))
tokens.push_back(tok->previous()->astOperand1());
for (const Token *t: tokens) {
if (t && t->valueType() && t->valueType()->pointer == 0 && t->valueType()->container)
return;
}
const Variable *var = tok->variable();
if (var && !var->isPointer()) {
if (!var->isLocal() || var->isStatic())
return;
}
if (var && (Token::Match(var->nameToken(), "%name% =") || Token::Match(var->nameToken(), "%varid% ; %varid% =", var->declarationId())))
return;
if (var && var->nameToken() == tok)
return;
}
// Uninitialized function argument
if (Token::Match(tok->astParent(), "[,(]")) {
const Token *parent = tok->astParent();
int count = 0;
if (Token::simpleMatch(parent, ",")) {
if (tok == parent->astOperand2())
++count;
while (Token::simpleMatch(parent, ",")) {
count++;
parent = parent->astParent();
}
}
if (Token::simpleMatch(parent, "(") && parent->astOperand1() != tok) {
if (parent->astOperand1()->function()) {
const Variable *argvar = parent->astOperand1()->function()->getArgumentVar(count);
if (argvar && argvar->isReference() && !argvar->isConst())
return;
}
}
}
// Avoid FP for array declaration
const Token *parent = tok->astParent();
while (parent && parent->str() == "[")
parent = parent->astParent();
if (!parent)
return;
if (!uninitStructMember.empty()) {
dataBase->reportError(tok,
Severity::SeverityType::error,
"bughuntingUninitStructMember",
"Cannot determine that '" + tok->expressionString() + "." + uninitStructMember + "' is initialized",
CWE_USE_OF_UNINITIALIZED_VARIABLE,
false,
value.type == ExprEngine::ValueType::BailoutValue);
return;
}
dataBase->reportError(tok,
Severity::SeverityType::error,
"bughuntingUninit",
"Cannot determine that '" + tok->expressionString() + "' is initialized",
CWE_USE_OF_UNINITIALIZED_VARIABLE,
false,
value.type == ExprEngine::ValueType::BailoutValue);
};
std::function<void(const Token *, const ExprEngine::Value &, ExprEngine::DataBase *)> checkFunctionCall = [=](const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase) {
if (!Token::Match(tok->astParent(), "[(,]"))
return;
const Token *parent = tok->astParent();
while (Token::simpleMatch(parent, ","))
parent = parent->astParent();
if (!parent || parent->str() != "(")
return;
int num = 0;
for (const Token *argTok: getArguments(parent->astOperand1())) {
--num;
if (argTok == tok) {
num = -num;
break;
}
}
if (num <= 0)
return;
if (parent->astOperand1()->function()) {
const Variable *arg = parent->astOperand1()->function()->getArgumentVar(num - 1);
if (arg && arg->nameToken()) {
std::string bad;
MathLib::bigint low;
if (arg->nameToken()->getCppcheckAttribute(TokenImpl::CppcheckAttributes::Type::LOW, &low)) {
if (!(tok->hasKnownIntValue() && tok->getKnownIntValue() >= low) && value.isLessThan(dataBase, low))
bad = "__cppcheck_low__(" + std::to_string(low) + ")";
}
MathLib::bigint high;
if (arg->nameToken()->getCppcheckAttribute(TokenImpl::CppcheckAttributes::Type::HIGH, &high)) {
if (!(tok->hasKnownIntValue() && tok->getKnownIntValue() <= high) && value.isGreaterThan(dataBase, high))
bad = "__cppcheck_high__(" + std::to_string(high) + ")";
}
if (!bad.empty()) {
dataBase->reportError(tok,
Severity::SeverityType::error,
"bughuntingInvalidArgValue",
"There is function call, cannot determine that " + std::to_string(num) + getOrdinalText(num) + " argument value meets the attribute " + bad,
CWE(0),
false);
return;
}
}
}
// Check invalid function argument values..
for (const Library::InvalidArgValue &invalidArgValue : Library::getInvalidArgValues(settings->library.validarg(parent->astOperand1(), num))) {
bool err = false;
std::string bad;
switch (invalidArgValue.type) {
case Library::InvalidArgValue::eq:
if (!tok->hasKnownIntValue() || tok->getKnownIntValue() == MathLib::toLongNumber(invalidArgValue.op1))
err = value.isEqual(dataBase, MathLib::toLongNumber(invalidArgValue.op1));
bad = "equals " + invalidArgValue.op1;
break;
case Library::InvalidArgValue::le:
if (!tok->hasKnownIntValue() || tok->getKnownIntValue() <= MathLib::toLongNumber(invalidArgValue.op1))
err = value.isLessThan(dataBase, MathLib::toLongNumber(invalidArgValue.op1) + 1);
bad = "less equal " + invalidArgValue.op1;
break;
case Library::InvalidArgValue::lt:
if (!tok->hasKnownIntValue() || tok->getKnownIntValue() < MathLib::toLongNumber(invalidArgValue.op1))
err = value.isLessThan(dataBase, MathLib::toLongNumber(invalidArgValue.op1));
bad = "less than " + invalidArgValue.op1;
break;
case Library::InvalidArgValue::ge:
if (!tok->hasKnownIntValue() || tok->getKnownIntValue() >= MathLib::toLongNumber(invalidArgValue.op1))
err = value.isGreaterThan(dataBase, MathLib::toLongNumber(invalidArgValue.op1) - 1);
bad = "greater equal " + invalidArgValue.op1;
break;
case Library::InvalidArgValue::gt:
if (!tok->hasKnownIntValue() || tok->getKnownIntValue() > MathLib::toLongNumber(invalidArgValue.op1))
err = value.isGreaterThan(dataBase, MathLib::toLongNumber(invalidArgValue.op1));
bad = "greater than " + invalidArgValue.op1;
break;
case Library::InvalidArgValue::range:
// TODO
err = value.isEqual(dataBase, MathLib::toLongNumber(invalidArgValue.op1));
err |= value.isEqual(dataBase, MathLib::toLongNumber(invalidArgValue.op2));
bad = "range " + invalidArgValue.op1 + "-" + invalidArgValue.op2;
break;
}
if (err) {
dataBase->reportError(tok, Severity::SeverityType::error, "bughuntingInvalidArgValue", "There is function call, cannot determine that " + std::to_string(num) + getOrdinalText(num) + " argument value is valid. Bad value: " + bad, CWE(0), false);
break;
}
}
// Uninitialized function argument..
if (settings->library.isuninitargbad(parent->astOperand1(), num) && settings->library.isnullargbad(parent->astOperand1(), num) && value.type == ExprEngine::ValueType::ArrayValue) {
const ExprEngine::ArrayValue &arrayValue = static_cast<const ExprEngine::ArrayValue &>(value);
auto index0 = std::make_shared<ExprEngine::IntRange>("0", 0, 0);
for (const auto &v: arrayValue.read(index0)) {
if (v.second->isUninit()) {
dataBase->reportError(tok, Severity::SeverityType::error, "bughuntingUninitArg", "There is function call, cannot determine that " + std::to_string(num) + getOrdinalText(num) + " argument is initialized.", CWE_USE_OF_UNINITIALIZED_VARIABLE, false);
break;
}
}
}
};
std::function<void(const Token *, const ExprEngine::Value &, ExprEngine::DataBase *)> checkAssignment = [=](const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase) {
if (!Token::simpleMatch(tok->astParent(), "="))
return;
const Token *lhs = tok->astParent()->astOperand1();
while (Token::simpleMatch(lhs, "."))
lhs = lhs->astOperand2();
if (!lhs || !lhs->variable() || !lhs->variable()->nameToken())
return;
const Token *vartok = lhs->variable()->nameToken();
MathLib::bigint low;
if (vartok->getCppcheckAttribute(TokenImpl::CppcheckAttributes::Type::LOW, &low)) {
if (value.isLessThan(dataBase, low))
dataBase->reportError(tok, Severity::SeverityType::error, "bughuntingAssign", "There is assignment, cannot determine that value is greater or equal with " + std::to_string(low), CWE_INCORRECT_CALCULATION, false);
}
MathLib::bigint high;
if (vartok->getCppcheckAttribute(TokenImpl::CppcheckAttributes::Type::HIGH, &high)) {
if (value.isGreaterThan(dataBase, high))
dataBase->reportError(tok, Severity::SeverityType::error, "bughuntingAssign", "There is assignment, cannot determine that value is lower or equal with " + std::to_string(high), CWE_INCORRECT_CALCULATION, false);
}
};
std::vector<ExprEngine::Callback> callbacks;
callbacks.push_back(bufferOverflow);
callbacks.push_back(divByZero);
callbacks.push_back(checkFunctionCall);
callbacks.push_back(checkAssignment);
#ifdef BUG_HUNTING_INTEGEROVERFLOW
callbacks.push_back(integerOverflow);
#endif
callbacks.push_back(uninit);
addBughuntingChecks(&callbacks);
std::ostringstream report;
ExprEngine::executeAllFunctions(errorLogger, tokenizer, settings, callbacks, report);

View File

@ -5,6 +5,7 @@ include($$PWD/../externals/externals.pri)
INCLUDEPATH += $$PWD
HEADERS += $${PWD}/analyzerinfo.h \
$${PWD}/astutils.h \
$${PWD}/bughuntingchecks.h \
$${PWD}/check.h \
$${PWD}/check64bit.h \
$${PWD}/checkassert.h \
@ -60,6 +61,7 @@ HEADERS += $${PWD}/analyzerinfo.h \
SOURCES += $${PWD}/analyzerinfo.cpp \
$${PWD}/astutils.cpp \
$${PWD}/bughuntingchecks.cpp \
$${PWD}/check.cpp \
$${PWD}/check64bit.cpp \
$${PWD}/checkassert.cpp \

View File

@ -150,7 +150,7 @@ private:
std::istringstream istr(code);
tokenizer.tokenize(istr, "test.cpp");
std::string ret;
std::function<void(const Token *, const ExprEngine::Value &, ExprEngine::DataBase *)> f = [&](const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase) {
ExprEngine::Callback f = [&](const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase) {
if (tok->str() != binop)
return;
const auto *b = dynamic_cast<const ExprEngine::BinOpResult *>(&value);
@ -193,7 +193,7 @@ private:
std::istringstream istr(code);
tokenizer.tokenize(istr, "test.cpp");
std::string ret;
std::function<void(const Token *, const ExprEngine::Value &, ExprEngine::DataBase *)> f = [&](const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase) {
ExprEngine::Callback f = [&](const Token *tok, const ExprEngine::Value &value, ExprEngine::DataBase *dataBase) {
(void)dataBase;
if ((linenr == 0 || linenr == tok->linenr()) && tok->expressionString() == str) {
if (!ret.empty())