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Fix #9279 Missing --check-library warning when memory leaks check assumes function is noreturn #4937

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Merged
orbitcowboy merged 4 commits into from
Apr 6, 2023
Merged

Fix #9279 Missing --check-library warning when memory leaks check assumes function is noreturn #4937

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f6f6a28
Fix #9279 Missing --check-library warning when memory leaks check ass…
chrchr-github Apr 6, 2023
2c18986
Format
chrchr-github Apr 6, 2023
5b57f71
Fix check, add tests
chrchr-github Apr 6, 2023
589580e
Format
chrchr-github Apr 6, 2023
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38 changes: 22 additions & 16 deletions lib/checkleakautovar.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -96,10 +96,9 @@ void VarInfo::print()
std::cout << "size=" << alloctype.size() << std::endl;
for (std::map<int, AllocInfo>::const_iterator it = alloctype.cbegin(); it != alloctype.cend(); ++it) {
std::string strusage;
const std::map<int, std::string>::const_iterator use =
possibleUsage.find(it->first);
const auto use = possibleUsage.find(it->first);
if (use != possibleUsage.end())
strusage = use->second;
strusage = use->second.first;

std::string status;
switch (it->second.status) {
Expand Down Expand Up @@ -133,11 +132,11 @@ void VarInfo::print()
}
}

void VarInfo::possibleUsageAll(const std::string &functionName)
void VarInfo::possibleUsageAll(const std::pair<std::string, Usage>& functionUsage)
{
possibleUsage.clear();
for (std::map<int, AllocInfo>::const_iterator it = alloctype.cbegin(); it != alloctype.cend(); ++it)
possibleUsage[it->first] = functionName;
possibleUsage[it->first] = functionUsage;
}


Expand Down Expand Up @@ -169,13 +168,13 @@ void CheckLeakAutoVar::deallocReturnError(const Token *tok, const Token *dealloc
reportError(locations, Severity::error, "deallocret", "$symbol:" + varname + "\nReturning/dereferencing '$symbol' after it is deallocated / released", CWE672, Certainty::normal);
}

void CheckLeakAutoVar::configurationInfo(const Token* tok, const std::string &functionName)
void CheckLeakAutoVar::configurationInfo(const Token* tok, const std::pair<std::string, VarInfo::Usage>& functionUsage)
{
if (mSettings->checkLibrary) {
if (mSettings->checkLibrary && functionUsage.second == VarInfo::USED) {
reportError(tok,
Severity::information,
"checkLibraryUseIgnore",
"--check-library: Function " + functionName + "() should have <use>/<leak-ignore> configuration");
"--check-library: Function " + functionUsage.first + "() should have <use>/<leak-ignore> configuration");
}
}

Expand Down Expand Up @@ -300,7 +299,7 @@ bool CheckLeakAutoVar::checkScope(const Token * const startToken,
throw InternalError(startToken, "Internal limit: CheckLeakAutoVar::checkScope() Maximum recursive count of 1000 reached.", InternalError::LIMIT);

std::map<int, VarInfo::AllocInfo> &alloctype = varInfo.alloctype;
std::map<int, std::string> &possibleUsage = varInfo.possibleUsage;
auto& possibleUsage = varInfo.possibleUsage;
const std::set<int> conditionalAlloc(varInfo.conditionalAlloc);

// Parse all tokens
Expand Down Expand Up @@ -671,8 +670,15 @@ bool CheckLeakAutoVar::checkScope(const Token * const startToken,
if (mTokenizer->isScopeNoReturn(tok->tokAt(2), &unknown)) {
if (!unknown)
varInfo.clear();
else if (!mSettings->library.isLeakIgnore(functionName) && !mSettings->library.isUse(functionName))
varInfo.possibleUsageAll(functionName);
else {
if (ftok->function() && !ftok->function()->isAttributeNoreturn() &&
!(ftok->function()->functionScope && mTokenizer->isScopeNoReturn(ftok->function()->functionScope->bodyEnd))) // check function scope
continue;
if (!mSettings->library.isLeakIgnore(functionName) && !mSettings->library.isUse(functionName)) {
const VarInfo::Usage usage = Token::simpleMatch(openingPar, "( )") ? VarInfo::NORET : VarInfo::USED; // TODO: check parameters passed to function
varInfo.possibleUsageAll({ functionName, usage });
}
}
}
}

Expand Down Expand Up @@ -870,7 +876,7 @@ void CheckLeakAutoVar::changeAllocStatus(VarInfo &varInfo, const VarInfo::AllocI
if (var != alloctype.end()) {
if (allocation.status == VarInfo::NOALLOC) {
// possible usage
varInfo.possibleUsage[arg->varId()] = tok->str();
varInfo.possibleUsage[arg->varId()] = { tok->str(), VarInfo::USED };
if (var->second.status == VarInfo::DEALLOC && arg->previous()->str() == "&")
varInfo.erase(arg->varId());
} else if (var->second.managed()) {
Expand Down Expand Up @@ -1006,11 +1012,11 @@ void CheckLeakAutoVar::leakIfAllocated(const Token *vartok,
const VarInfo &varInfo)
{
const std::map<int, VarInfo::AllocInfo> &alloctype = varInfo.alloctype;
const std::map<int, std::string> &possibleUsage = varInfo.possibleUsage;
const auto& possibleUsage = varInfo.possibleUsage;

const std::map<int, VarInfo::AllocInfo>::const_iterator var = alloctype.find(vartok->varId());
if (var != alloctype.cend() && var->second.status == VarInfo::ALLOC) {
const std::map<int, std::string>::const_iterator use = possibleUsage.find(vartok->varId());
const auto use = possibleUsage.find(vartok->varId());
if (use == possibleUsage.end()) {
leakError(vartok, vartok->str(), var->second.type);
} else {
Expand All @@ -1022,7 +1028,7 @@ void CheckLeakAutoVar::leakIfAllocated(const Token *vartok,
void CheckLeakAutoVar::ret(const Token *tok, VarInfo &varInfo, const bool isEndOfScope)
{
const std::map<int, VarInfo::AllocInfo> &alloctype = varInfo.alloctype;
const std::map<int, std::string> &possibleUsage = varInfo.possibleUsage;
const auto& possibleUsage = varInfo.possibleUsage;
std::vector<int> toRemove;

const SymbolDatabase *symbolDatabase = mTokenizer->getSymbolDatabase();
Expand Down Expand Up @@ -1071,7 +1077,7 @@ void CheckLeakAutoVar::ret(const Token *tok, VarInfo &varInfo, const bool isEndO
deallocReturnError(tok, it->second.allocTok, var->name());

else if (!used && !it->second.managed()) {
const std::map<int, std::string>::const_iterator use = possibleUsage.find(varid);
const auto use = possibleUsage.find(varid);
if (use == possibleUsage.end()) {
leakError(tok, var->name(), it->second.type);
} else {
Expand Down
9 changes: 5 additions & 4 deletions lib/checkleakautovar.h
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Original file line number Diff line number Diff line change
Expand Up @@ -55,8 +55,9 @@ class CPPCHECKLIB VarInfo {
return status < 0;
}
};
enum Usage { USED, NORET };
std::map<int, AllocInfo> alloctype;
std::map<int, std::string> possibleUsage;
std::map<int, std::pair<std::string, Usage>> possibleUsage;
std::set<int> conditionalAlloc;
std::set<int> referenced;

Expand Down Expand Up @@ -92,7 +93,7 @@ class CPPCHECKLIB VarInfo {
}

/** set possible usage for all variables */
void possibleUsageAll(const std::string &functionName);
void possibleUsageAll(const std::pair<std::string, Usage>& functionUsage);

void print();
};
Expand Down Expand Up @@ -159,12 +160,12 @@ class CPPCHECKLIB CheckLeakAutoVar : public Check {
void doubleFreeError(const Token *tok, const Token *prevFreeTok, const std::string &varname, int type);

/** message: user configuration is needed to complete analysis */
void configurationInfo(const Token* tok, const std::string &functionName);
void configurationInfo(const Token* tok, const std::pair<std::string, VarInfo::Usage>& functionUsage);

void getErrorMessages(ErrorLogger *errorLogger, const Settings *settings) const override {
CheckLeakAutoVar c(nullptr, settings, errorLogger);
c.deallocReturnError(nullptr, nullptr, "p");
c.configurationInfo(nullptr, "f"); // user configuration is needed to complete analysis
c.configurationInfo(nullptr, { "f", VarInfo::USED }); // user configuration is needed to complete analysis
c.doubleFreeError(nullptr, nullptr, "varname", 0);
}

Expand Down
77 changes: 58 additions & 19 deletions test/testleakautovar.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -104,7 +104,6 @@ class TestLeakAutoVar : public TestFixture {
TEST_CASE(freopen2);

TEST_CASE(deallocuse1);
TEST_CASE(deallocuse2);
TEST_CASE(deallocuse3);
TEST_CASE(deallocuse4);
TEST_CASE(deallocuse5); // #4018: FP. free(p), p = 0;
Expand Down Expand Up @@ -508,8 +507,8 @@ class TestLeakAutoVar : public TestFixture {
settings = s;
}

void assign24() { // #7440
check("void f() {\n"
void assign24() {
check("void f() {\n" // #7440
" char* data = new char[100];\n"
" char** dataPtr = &data;\n"
" delete[] *dataPtr;\n"
Expand All @@ -523,6 +522,46 @@ class TestLeakAutoVar : public TestFixture {
" delete[] *dataPtr;\n"
"}\n", true);
ASSERT_EQUALS("", errout.str());

check("void f() {\n" // #9279
" int* p = new int;\n"
" *p = 42;\n"
" g();\n"
"}\n", /*cpp*/ true);
ASSERT_EQUALS("[test.cpp:4]: (information) --check-library: Function g() should have <noreturn> configuration\n",
errout.str());

check("void g();\n"
"void f() {\n"
" int* p = new int;\n"
" *p = 42;\n"
" g();\n"
"}\n", /*cpp*/ true);
ASSERT_EQUALS("[test.cpp:6]: (error) Memory leak: p\n", errout.str());

check("void g() {}\n"
"void f() {\n"
" int* p = new int;\n"
" *p = 42;\n"
" g();\n"
"}\n", /*cpp*/ true);
ASSERT_EQUALS("[test.cpp:6]: (error) Memory leak: p\n", errout.str());

check("[[noreturn]] void g();\n"
"void f() {\n"
" int* p = new int;\n"
" *p = 42;\n"
" g();\n"
"}\n", /*cpp*/ true);
ASSERT_EQUALS("", errout.str());

check("void g() { exit(1); }\n"
"void f() {\n"
" int* p = new int;\n"
" *p = 42;\n"
" g();\n"
"}\n", /*cpp*/ true);
ASSERT_EQUALS("", errout.str());
}

void isAutoDealloc() {
Expand Down Expand Up @@ -647,20 +686,6 @@ class TestLeakAutoVar : public TestFixture {
ASSERT_EQUALS("[test.c:3]: (error) Dereferencing 'p' after it is deallocated / released\n", errout.str());
}

void deallocuse2() {
check("void f(char *p) {\n"
" free(p);\n"
" strcpy(a, p);\n"
"}");
TODO_ASSERT_EQUALS("error (free,use)", "[test.c:3]: (information) --check-library: Function strcpy() should have <noreturn> configuration\n", errout.str());

check("void f(char *p) {\n" // #3041 - assigning pointer when it's used
" free(p);\n"
" strcpy(a, p=b());\n"
"}");
TODO_ASSERT_EQUALS("", "[test.c:3]: (information) --check-library: Function strcpy() should have <noreturn> configuration\n", errout.str());
}

void deallocuse3() {
check("void f(struct str *p) {\n"
" free(p);\n"
Expand Down Expand Up @@ -1437,8 +1462,7 @@ class TestLeakAutoVar : public TestFixture {
" char *p = malloc(10);\n"
" fatal_error();\n"
"}");
ASSERT_EQUALS("[test.c:3]: (information) --check-library: Function fatal_error() should have <noreturn> configuration\n"
"[test.c:4]: (information) --check-library: Function fatal_error() should have <use>/<leak-ignore> configuration\n",
ASSERT_EQUALS("[test.c:3]: (information) --check-library: Function fatal_error() should have <noreturn> configuration\n",
errout.str());
}

Expand Down Expand Up @@ -2711,6 +2735,7 @@ class TestLeakAutoVarStrcpy : public TestFixture {
LOAD_LIB_2(settings.library, "std.cfg");

TEST_CASE(returnedValue); // #9298
TEST_CASE(deallocuse2);
TEST_CASE(fclose_false_positive); // #9575
}

Expand All @@ -2724,6 +2749,20 @@ class TestLeakAutoVarStrcpy : public TestFixture {
ASSERT_EQUALS("", errout.str());
}

void deallocuse2() {
check("void f(char *p) {\n"
" free(p);\n"
" strcpy(a, p);\n"
"}");
TODO_ASSERT_EQUALS("error (free,use)", "", errout.str());

check("void f(char *p) {\n" // #3041 - assigning pointer when it's used
" free(p);\n"
" strcpy(a, p=b());\n"
"}");
ASSERT_EQUALS("", errout.str());
}

void fclose_false_positive() { // #9575
check("int f(FILE *fp) { return fclose(fp); }");
ASSERT_EQUALS("", errout.str());
Expand Down