cppcheck/lib/ctu.cpp

560 lines
24 KiB
C++

/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2019 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 "ctu.h"
#include "astutils.h"
#include "symboldatabase.h"
#include <tinyxml2.h>
#include <iterator> // back_inserter
//---------------------------------------------------------------------------
static const char ATTR_CALL_ID[] = "call-id";
static const char ATTR_CALL_FUNCNAME[] = "call-funcname";
static const char ATTR_CALL_ARGNR[] = "call-argnr";
static const char ATTR_CALL_ARGEXPR[] = "call-argexpr";
static const char ATTR_CALL_ARGVALUETYPE[] = "call-argvaluetype";
static const char ATTR_CALL_ARGVALUE[] = "call-argvalue";
static const char ATTR_WARNING[] = "warning";
static const char ATTR_LOC_FILENAME[] = "file";
static const char ATTR_LOC_LINENR[] = "line";
static const char ATTR_LOC_COLUMN[] = "col";
static const char ATTR_INFO[] = "info";
static const char ATTR_MY_ID[] = "my-id";
static const char ATTR_MY_ARGNR[] = "my-argnr";
static const char ATTR_MY_ARGNAME[] = "my-argname";
static const char ATTR_VALUE[] = "value";
int CTU::maxCtuDepth = 2;
std::string CTU::getFunctionId(const Tokenizer *tokenizer, const Function *function)
{
return tokenizer->list.file(function->tokenDef) + ':' + MathLib::toString(function->tokenDef->linenr()) + ':' + MathLib::toString(function->tokenDef->column());
}
CTU::FileInfo::Location::Location(const Tokenizer *tokenizer, const Token *tok)
: fileName(tokenizer->list.file(tok))
, lineNumber(tok->linenr())
, column(tok->column())
{
}
std::string CTU::FileInfo::toString() const
{
std::ostringstream out;
// Function calls..
for (const CTU::FileInfo::FunctionCall &functionCall : functionCalls) {
out << functionCall.toXmlString();
}
// Nested calls..
for (const CTU::FileInfo::NestedCall &nestedCall : nestedCalls) {
out << nestedCall.toXmlString() << "\n";
}
return out.str();
}
std::string CTU::FileInfo::CallBase::toBaseXmlString() const
{
std::ostringstream out;
out << " " << ATTR_CALL_ID << "=\"" << callId << "\""
<< " " << ATTR_CALL_FUNCNAME << "=\"" << callFunctionName << "\""
<< " " << ATTR_CALL_ARGNR << "=\"" << callArgNr << "\""
<< " " << ATTR_LOC_FILENAME << "=\"" << location.fileName << "\""
<< " " << ATTR_LOC_LINENR << "=\"" << location.lineNumber << "\""
<< " " << ATTR_LOC_COLUMN << "=\"" << location.column << "\"";
return out.str();
}
std::string CTU::FileInfo::FunctionCall::toXmlString() const
{
std::ostringstream out;
out << "<function-call"
<< toBaseXmlString()
<< " " << ATTR_CALL_ARGEXPR << "=\"" << callArgumentExpression << "\""
<< " " << ATTR_CALL_ARGVALUETYPE << "=\"" << callValueType << "\""
<< " " << ATTR_CALL_ARGVALUE << "=\"" << callArgValue << "\"";
if (warning)
out << " " << ATTR_WARNING << "=\"true\"";
if (callValuePath.empty())
out << "/>";
else {
out << ">\n";
for (const ErrorLogger::ErrorMessage::FileLocation &loc : callValuePath)
out << " <path"
<< " " << ATTR_LOC_FILENAME << "=\"" << loc.getfile() << "\""
<< " " << ATTR_LOC_LINENR << "=\"" << loc.line << "\""
<< " " << ATTR_LOC_COLUMN << "=\"" << loc.column << "\""
<< " " << ATTR_INFO << "=\"" << loc.getinfo() << "\"/>\n";
out << "</function-call>";
}
return out.str();
}
std::string CTU::FileInfo::NestedCall::toXmlString() const
{
std::ostringstream out;
out << "<function-call"
<< toBaseXmlString()
<< " " << ATTR_MY_ID << "=\"" << myId << "\""
<< " " << ATTR_MY_ARGNR << "=\"" << myArgNr << "\""
<< "/>";
return out.str();
}
std::string CTU::FileInfo::UnsafeUsage::toString() const
{
std::ostringstream out;
out << " <unsafe-usage"
<< " " << ATTR_MY_ID << "=\"" << myId << '\"'
<< " " << ATTR_MY_ARGNR << "=\"" << myArgNr << '\"'
<< " " << ATTR_MY_ARGNAME << "=\"" << myArgumentName << '\"'
<< " " << ATTR_LOC_FILENAME << "=\"" << location.fileName << '\"'
<< " " << ATTR_LOC_LINENR << "=\"" << location.lineNumber << '\"'
<< " " << ATTR_LOC_COLUMN << "=\"" << location.column << '\"'
<< " " << ATTR_VALUE << "=\"" << value << "\""
<< "/>\n";
return out.str();
}
std::string CTU::toString(const std::list<CTU::FileInfo::UnsafeUsage> &unsafeUsage)
{
std::ostringstream ret;
for (const CTU::FileInfo::UnsafeUsage &u : unsafeUsage)
ret << u.toString();
return ret.str();
}
CTU::FileInfo::CallBase::CallBase(const Tokenizer *tokenizer, const Token *callToken)
: callId(getFunctionId(tokenizer, callToken->function()))
, callArgNr(0)
, callFunctionName(callToken->next()->astOperand1()->expressionString())
, location(CTU::FileInfo::Location(tokenizer, callToken))
{
}
CTU::FileInfo::NestedCall::NestedCall(const Tokenizer *tokenizer, const Function *myFunction, const Token *callToken)
: CallBase(tokenizer, callToken)
, myId(getFunctionId(tokenizer, myFunction))
, myArgNr(0)
{
}
static std::string readAttrString(const tinyxml2::XMLElement *e, const char *attr, bool *error)
{
const char *value = e->Attribute(attr);
if (!value && error)
*error = true;
return value ? value : "";
}
static long long readAttrInt(const tinyxml2::XMLElement *e, const char *attr, bool *error)
{
const char *value = e->Attribute(attr);
if (!value && error)
*error = true;
return value ? std::atoi(value) : 0;
}
bool CTU::FileInfo::CallBase::loadBaseFromXml(const tinyxml2::XMLElement *xmlElement)
{
bool error = false;
callId = readAttrString(xmlElement, ATTR_CALL_ID, &error);
callFunctionName = readAttrString(xmlElement, ATTR_CALL_FUNCNAME, &error);
callArgNr = readAttrInt(xmlElement, ATTR_CALL_ARGNR, &error);
location.fileName = readAttrString(xmlElement, ATTR_LOC_FILENAME, &error);
location.lineNumber = readAttrInt(xmlElement, ATTR_LOC_LINENR, &error);
location.column = readAttrInt(xmlElement, ATTR_LOC_COLUMN, &error);
return !error;
}
bool CTU::FileInfo::FunctionCall::loadFromXml(const tinyxml2::XMLElement *xmlElement)
{
if (!loadBaseFromXml(xmlElement))
return false;
bool error=false;
callArgumentExpression = readAttrString(xmlElement, ATTR_CALL_ARGEXPR, &error);
callValueType = (ValueFlow::Value::ValueType)readAttrInt(xmlElement, ATTR_CALL_ARGVALUETYPE, &error);
callArgValue = readAttrInt(xmlElement, ATTR_CALL_ARGVALUE, &error);
const char *w = xmlElement->Attribute(ATTR_WARNING);
warning = w && std::strcmp(w, "true") == 0;
for (const tinyxml2::XMLElement *e2 = xmlElement->FirstChildElement(); !error && e2; e2 = e2->NextSiblingElement()) {
if (std::strcmp(e2->Name(), "path") != 0)
continue;
ErrorLogger::ErrorMessage::FileLocation loc;
loc.setfile(readAttrString(e2, ATTR_LOC_FILENAME, &error));
loc.line = readAttrInt(e2, ATTR_LOC_LINENR, &error);
loc.column = readAttrInt(e2, ATTR_LOC_COLUMN, &error);
loc.setinfo(readAttrString(e2, ATTR_INFO, &error));
}
return !error;
}
bool CTU::FileInfo::NestedCall::loadFromXml(const tinyxml2::XMLElement *xmlElement)
{
if (!loadBaseFromXml(xmlElement))
return false;
bool error = false;
myId = readAttrString(xmlElement, ATTR_MY_ID, &error);
myArgNr = readAttrInt(xmlElement, ATTR_MY_ARGNR, &error);
return !error;
}
void CTU::FileInfo::loadFromXml(const tinyxml2::XMLElement *xmlElement)
{
for (const tinyxml2::XMLElement *e = xmlElement->FirstChildElement(); e; e = e->NextSiblingElement()) {
if (std::strcmp(e->Name(), "function-call") == 0) {
FunctionCall functionCall;
if (functionCall.loadFromXml(e))
functionCalls.push_back(functionCall);
} else if (std::strcmp(e->Name(), "nested-call") == 0) {
NestedCall nestedCall;
if (nestedCall.loadFromXml(e))
nestedCalls.push_back(nestedCall);
}
}
}
std::map<std::string, std::list<const CTU::FileInfo::CallBase *>> CTU::FileInfo::getCallsMap() const
{
std::map<std::string, std::list<const CTU::FileInfo::CallBase *>> ret;
for (const CTU::FileInfo::NestedCall &nc : nestedCalls)
ret[nc.callId].push_back(&nc);
for (const CTU::FileInfo::FunctionCall &fc : functionCalls)
ret[fc.callId].push_back(&fc);
return ret;
}
std::list<CTU::FileInfo::UnsafeUsage> CTU::loadUnsafeUsageListFromXml(const tinyxml2::XMLElement *xmlElement)
{
std::list<CTU::FileInfo::UnsafeUsage> ret;
for (const tinyxml2::XMLElement *e = xmlElement->FirstChildElement(); e; e = e->NextSiblingElement()) {
if (std::strcmp(e->Name(), "unsafe-usage") != 0)
continue;
bool error = false;
FileInfo::UnsafeUsage unsafeUsage;
unsafeUsage.myId = readAttrString(e, ATTR_MY_ID, &error);
unsafeUsage.myArgNr = readAttrInt(e, ATTR_MY_ARGNR, &error);
unsafeUsage.myArgumentName = readAttrString(e, ATTR_MY_ARGNAME, &error);
unsafeUsage.location.fileName = readAttrString(e, ATTR_LOC_FILENAME, &error);
unsafeUsage.location.lineNumber = readAttrInt(e, ATTR_LOC_LINENR, &error);
unsafeUsage.location.column = readAttrInt(e, ATTR_LOC_COLUMN, &error);
unsafeUsage.value = readAttrInt(e, ATTR_VALUE, &error);
if (!error)
ret.push_back(unsafeUsage);
}
return ret;
}
static int isCallFunction(const Scope *scope, int argnr, const Token **tok)
{
const Variable * const argvar = scope->function->getArgumentVar(argnr);
if (!argvar->isPointer())
return -1;
for (const Token *tok2 = scope->bodyStart; tok2 != scope->bodyEnd; tok2 = tok2->next()) {
if (tok2->variable() != argvar)
continue;
if (!Token::Match(tok2->previous(), "[(,] %var% [,)]"))
break;
int argnr2 = 1;
const Token *prev = tok2;
while (prev && prev->str() != "(") {
if (Token::Match(prev,"]|)"))
prev = prev->link();
else if (prev->str() == ",")
++argnr2;
prev = prev->previous();
}
if (!prev || !Token::Match(prev->previous(), "%name% ("))
break;
if (!prev->astOperand1() || !prev->astOperand1()->function())
break;
*tok = prev->previous();
return argnr2;
}
return -1;
}
CTU::FileInfo *CTU::getFileInfo(const Tokenizer *tokenizer)
{
const SymbolDatabase * const symbolDatabase = tokenizer->getSymbolDatabase();
FileInfo *fileInfo = new FileInfo;
// Parse all functions in TU
for (const Scope &scope : symbolDatabase->scopeList) {
if (!scope.isExecutable() || scope.type != Scope::eFunction || !scope.function)
continue;
const Function *const function = scope.function;
// source function calls
for (const Token *tok = scope.bodyStart; tok != scope.bodyEnd; tok = tok->next()) {
if (tok->str() != "(" || !tok->astOperand1() || !tok->astOperand2())
continue;
if (!tok->astOperand1()->function())
continue;
const std::vector<const Token *> args(getArguments(tok->previous()));
for (int argnr = 0; argnr < args.size(); ++argnr) {
const Token *argtok = args[argnr];
if (!argtok)
continue;
for (const ValueFlow::Value &value : argtok->values()) {
if ((!value.isIntValue() || value.intvalue != 0 || value.isInconclusive()) && !value.isBufferSizeValue())
continue;
FileInfo::FunctionCall functionCall;
functionCall.callValueType = value.valueType;
functionCall.callId = getFunctionId(tokenizer, tok->astOperand1()->function());
functionCall.callFunctionName = tok->astOperand1()->expressionString();
functionCall.location = FileInfo::Location(tokenizer,tok);
functionCall.callArgNr = argnr + 1;
functionCall.callArgumentExpression = argtok->expressionString();
functionCall.callArgValue = value.intvalue;
functionCall.warning = !value.errorSeverity();
for (const ErrorPathItem &i : value.errorPath) {
ErrorLogger::ErrorMessage::FileLocation loc;
loc.setfile(tokenizer->list.file(i.first));
loc.line = i.first->linenr();
loc.column = i.first->column();
loc.setinfo(i.second);
functionCall.callValuePath.push_back(loc);
}
fileInfo->functionCalls.push_back(functionCall);
}
// array
if (argtok->variable() && argtok->variable()->isArray() && argtok->variable()->dimensions().size()==1 && argtok->variable()->dimension(0)>1) {
FileInfo::FunctionCall functionCall;
functionCall.callValueType = ValueFlow::Value::ValueType::BUFFER_SIZE;
functionCall.callId = getFunctionId(tokenizer, tok->astOperand1()->function());
functionCall.callFunctionName = tok->astOperand1()->expressionString();
functionCall.location = FileInfo::Location(tokenizer, tok);
functionCall.callArgNr = argnr + 1;
functionCall.callArgumentExpression = argtok->expressionString();
functionCall.callArgValue = argtok->variable()->dimension(0) * argtok->valueType()->typeSize(*tokenizer->getSettings());
functionCall.warning = false;
fileInfo->functionCalls.push_back(functionCall);
}
// &var => buffer
if (argtok->isUnaryOp("&") && argtok->astOperand1()->variable() && argtok->astOperand1()->valueType() && !argtok->astOperand1()->variable()->isArray()) {
FileInfo::FunctionCall functionCall;
functionCall.callValueType = ValueFlow::Value::ValueType::BUFFER_SIZE;
functionCall.callId = getFunctionId(tokenizer, tok->astOperand1()->function());
functionCall.callFunctionName = tok->astOperand1()->expressionString();
functionCall.location = FileInfo::Location(tokenizer, tok);
functionCall.callArgNr = argnr + 1;
functionCall.callArgumentExpression = argtok->expressionString();
functionCall.callArgValue = argtok->astOperand1()->valueType()->typeSize(*tokenizer->getSettings());
functionCall.warning = false;
fileInfo->functionCalls.push_back(functionCall);
}
// pointer to uninitialized data..
if (!argtok->isUnaryOp("&"))
continue;
argtok = argtok->astOperand1();
if (!argtok || !argtok->valueType() || argtok->valueType()->pointer != 0)
continue;
if (argtok->values().size() != 1U)
continue;
const ValueFlow::Value &v = argtok->values().front();
if (v.valueType == ValueFlow::Value::ValueType::UNINIT && !v.isInconclusive()) {
FileInfo::FunctionCall functionCall;
functionCall.callValueType = ValueFlow::Value::ValueType::UNINIT;
functionCall.callId = getFunctionId(tokenizer, tok->astOperand1()->function());
functionCall.callFunctionName = tok->astOperand1()->expressionString();
functionCall.location = FileInfo::Location(tokenizer, tok);
functionCall.callArgNr = argnr + 1;
functionCall.callArgValue = 0;
functionCall.callArgumentExpression = argtok->expressionString();
functionCall.warning = false;
fileInfo->functionCalls.push_back(functionCall);
continue;
}
}
}
// Nested function calls
for (int argnr = 0; argnr < function->argCount(); ++argnr) {
const Token *tok;
const int argnr2 = isCallFunction(&scope, argnr, &tok);
if (argnr2 > 0) {
FileInfo::NestedCall nestedCall(tokenizer, function, tok);
nestedCall.myArgNr = argnr + 1;
nestedCall.callArgNr = argnr2;
fileInfo->nestedCalls.push_back(nestedCall);
}
}
}
return fileInfo;
}
static std::list<std::pair<const Token *, MathLib::bigint>> getUnsafeFunction(const Tokenizer *tokenizer, const Settings *settings, const Scope *scope, int argnr, const Check *check, bool (*isUnsafeUsage)(const Check *check, const Token *argtok, MathLib::bigint *value))
{
std::list<std::pair<const Token *, MathLib::bigint>> ret;
const Variable * const argvar = scope->function->getArgumentVar(argnr);
if (!argvar->isPointer())
return ret;
for (const Token *tok2 = scope->bodyStart; tok2 != scope->bodyEnd; tok2 = tok2->next()) {
if (Token::Match(tok2, ")|else {")) {
tok2 = tok2->linkAt(1);
if (Token::findmatch(tok2->link(), "return|throw", tok2))
return ret;
if (isVariableChanged(tok2->link(), tok2, argvar->declarationId(), false, settings, tokenizer->isCPP()))
return ret;
}
if (Token::Match(tok2, "%oror%|&&|?")) {
tok2 = tok2->findExpressionStartEndTokens().second;
continue;
}
if (tok2->variable() != argvar)
continue;
MathLib::bigint value = 0;
if (!isUnsafeUsage(check, tok2, &value))
return ret; // TODO: Is this a read? then continue..
ret.emplace_back(tok2, value);
return ret;
}
return ret;
}
std::list<CTU::FileInfo::UnsafeUsage> CTU::getUnsafeUsage(const Tokenizer *tokenizer, const Settings *settings, const Check *check, bool (*isUnsafeUsage)(const Check *check, const Token *argtok, MathLib::bigint *_value))
{
std::list<CTU::FileInfo::UnsafeUsage> unsafeUsage;
// Parse all functions in TU
const SymbolDatabase * const symbolDatabase = tokenizer->getSymbolDatabase();
for (const Scope &scope : symbolDatabase->scopeList) {
if (!scope.isExecutable() || scope.type != Scope::eFunction || !scope.function)
continue;
const Function *const function = scope.function;
// "Unsafe" functions unconditionally reads data before it is written..
for (int argnr = 0; argnr < function->argCount(); ++argnr) {
for (const std::pair<const Token *, MathLib::bigint> &v : getUnsafeFunction(tokenizer, settings, &scope, argnr, check, isUnsafeUsage)) {
const Token *tok = v.first;
MathLib::bigint value = v.second;
unsafeUsage.emplace_back(CTU::getFunctionId(tokenizer, function), argnr+1, tok->str(), CTU::FileInfo::Location(tokenizer,tok), value);
}
}
}
return unsafeUsage;
}
static bool findPath(const std::string &callId,
nonneg int callArgNr,
MathLib::bigint unsafeValue,
CTU::FileInfo::InvalidValueType invalidValue,
const std::map<std::string, std::list<const CTU::FileInfo::CallBase *>> &callsMap,
const CTU::FileInfo::CallBase *path[10],
int index,
bool warning)
{
if (index >= CTU::maxCtuDepth || index >= 10)
return false;
const std::map<std::string, std::list<const CTU::FileInfo::CallBase *>>::const_iterator it = callsMap.find(callId);
if (it == callsMap.end())
return false;
for (const CTU::FileInfo::CallBase *c : it->second) {
if (c->callArgNr != callArgNr)
continue;
const CTU::FileInfo::FunctionCall *functionCall = dynamic_cast<const CTU::FileInfo::FunctionCall *>(c);
if (functionCall) {
if (!warning && functionCall->warning)
continue;
switch (invalidValue) {
case CTU::FileInfo::InvalidValueType::null:
if (functionCall->callValueType != ValueFlow::Value::ValueType::INT || functionCall->callArgValue != 0)
continue;
break;
case CTU::FileInfo::InvalidValueType::uninit:
if (functionCall->callValueType != ValueFlow::Value::ValueType::UNINIT)
continue;
break;
case CTU::FileInfo::InvalidValueType::bufferOverflow:
if (functionCall->callValueType != ValueFlow::Value::ValueType::BUFFER_SIZE)
continue;
if (unsafeValue < 0 || unsafeValue >= functionCall->callArgValue)
break;
continue;
};
path[index] = functionCall;
return true;
}
const CTU::FileInfo::NestedCall *nestedCall = dynamic_cast<const CTU::FileInfo::NestedCall *>(c);
if (!nestedCall)
continue;
if (findPath(nestedCall->myId, nestedCall->myArgNr, unsafeValue, invalidValue, callsMap, path, index + 1, warning)) {
path[index] = nestedCall;
return true;
}
}
return false;
}
std::list<ErrorLogger::ErrorMessage::FileLocation> CTU::FileInfo::getErrorPath(InvalidValueType invalidValue,
const CTU::FileInfo::UnsafeUsage &unsafeUsage,
const std::map<std::string, std::list<const CTU::FileInfo::CallBase *>> &callsMap,
const char info[],
const FunctionCall * * const functionCallPtr,
bool warning) const
{
std::list<ErrorLogger::ErrorMessage::FileLocation> locationList;
const CTU::FileInfo::CallBase *path[10] = {nullptr};
if (!findPath(unsafeUsage.myId, unsafeUsage.myArgNr, unsafeUsage.value, invalidValue, callsMap, path, 0, warning))
return locationList;
const std::string value1 = (invalidValue == InvalidValueType::null) ? "null" : "uninitialized";
for (int index = 9; index >= 0; index--) {
if (!path[index])
continue;
const CTU::FileInfo::FunctionCall *functionCall = dynamic_cast<const CTU::FileInfo::FunctionCall *>(path[index]);
if (functionCall) {
if (functionCallPtr)
*functionCallPtr = functionCall;
std::copy(functionCall->callValuePath.cbegin(), functionCall->callValuePath.cend(), std::back_inserter(locationList));
}
ErrorLogger::ErrorMessage::FileLocation fileLoc(path[index]->location.fileName, path[index]->location.lineNumber, path[index]->location.column);
fileLoc.setinfo("Calling function " + path[index]->callFunctionName + ", " + MathLib::toString(path[index]->callArgNr) + getOrdinalText(path[index]->callArgNr) + " argument is " + value1);
locationList.push_back(fileLoc);
}
ErrorLogger::ErrorMessage::FileLocation fileLoc2(unsafeUsage.location.fileName, unsafeUsage.location.lineNumber, unsafeUsage.location.column);
fileLoc2.setinfo(replaceStr(info, "ARG", unsafeUsage.myArgumentName));
locationList.push_back(fileLoc2);
return locationList;
}