walkero
/
cppcheck
1
0
Fork 0
Code Issues Pull Requests Projects Releases 1 Wiki Activity

Merge pull request #2682 from pfultz2/check-mutexes 

Add new check for incorrect usage of mutexes and lock guards
This commit is contained in:
Daniel Marjamäki 2020-06-25 16:21:36 +02:00 committed by GitHub
parent 426c6d84ca 3c10a9c659
commit ec8fbb1580
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
5 changed files with 200 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

61
lib/checkstl.cpp
View File

@ -46,11 +46,13 @@ static const struct CWE CWE398(398U); // Indicator of Poor Code Quality
static const struct CWE CWE597(597U); // Use of Wrong Operator in String Comparison
static const struct CWE CWE628(628U); // Function Call with Incorrectly Specified Arguments
static const struct CWE CWE664(664U); // Improper Control of a Resource Through its Lifetime
static const struct CWE CWE667(667U); // Improper Locking
static const struct CWE CWE704(704U); // Incorrect Type Conversion or Cast
static const struct CWE CWE762(762U); // Mismatched Memory Management Routines
static const struct CWE CWE786(786U); // Access of Memory Location Before Start of Buffer
static const struct CWE CWE788(788U); // Access of Memory Location After End of Buffer
static const struct CWE CWE825(825U); // Expired Pointer Dereference
static const struct CWE CWE833(833U); // Deadlock
static const struct CWE CWE834(834U); // Excessive Iteration
void CheckStl::outOfBounds()
@ -2391,3 +2393,62 @@ void CheckStl::useStlAlgorithm()
}
}
}
static bool isMutex(const Variable* var)
{
const Token* tok = Token::typeDecl(var->nameToken()).first;
return Token::Match(tok, "std :: mutex|recursive_mutex|timed_mutex|recursive_timed_mutex|shared_mutex");
}
static bool isLockGuard(const Variable* var)
{
const Token* tok = Token::typeDecl(var->nameToken()).first;
return Token::Match(tok, "std :: lock_guard|unique_lock|scoped_lock");
}
static bool isLocalMutex(const Variable* var, const Scope* scope)
{
if (!var)
return false;
return !var->isReference() && !var->isRValueReference() && !var->isStatic() && var->scope() == scope;
}
void CheckStl::globalLockGuardError(const Token* tok)
{
reportError(tok, Severity::warning,
"globalLockGuard",
"Lock guard is defined globally. Lock guards are intended to be local. A global lock guard could lead to a deadlock since it won't unlock until the end of the program.", CWE833, false);
}
void CheckStl::localMutexError(const Token* tok)
{
reportError(tok, Severity::warning,
"localMutex",
"The lock is ineffective because the mutex is locked at the same scope as the mutex itself.", CWE667, false);
}
void CheckStl::checkMutexes()
{
for (const Scope *function : mTokenizer->getSymbolDatabase()->functionScopes) {
for (const Token *tok = function->bodyStart; tok != function->bodyEnd; tok = tok->next()) {
const Variable* var = tok->variable();
if (!var)
continue;
if (Token::Match(tok, "%var% . lock ( )")) {
if (!isMutex(var))
continue;
if (isLocalMutex(var, tok->scope()))
localMutexError(tok);
} else if (Token::Match(tok, "%var% (|{ %var% )|}")) {
if (!isLockGuard(var))
continue;
const Variable* mvar = tok->tokAt(2)->variable();
if (var->isStatic() || var->isGlobal())
globalLockGuardError(tok);
else if (isLocalMutex(mvar, tok->scope()))
localMutexError(tok);
}
}
}
}

11
lib/checkstl.h
View File

@ -84,6 +84,7 @@ public:
checkStl.stlBoundaries();
checkStl.checkDereferenceInvalidIterator();
checkStl.checkMutexes();
// Style check
checkStl.size();
@ -185,6 +186,8 @@ public:
/** @brief Look for loops that can replaced with std algorithms */
void useStlAlgorithm();
void checkMutexes();
private:
bool isContainerSize(const Token *containerToken, const Token *expr) const;
@ -229,6 +232,9 @@ private:
void useStlAlgorithmError(const Token *tok, const std::string &algoName);
void globalLockGuardError(const Token *tok);
void localMutexError(const Token *tok);
void getErrorMessages(ErrorLogger* errorLogger, const Settings* settings) const OVERRIDE {
ErrorPath errorPath;
CheckStl c(nullptr, settings, errorLogger);
@ -265,6 +271,8 @@ private:
c.dereferenceInvalidIteratorError(nullptr, "i");
c.readingEmptyStlContainerError(nullptr);
c.useStlAlgorithmError(nullptr, "");
c.globalLockGuardError(nullptr);
c.localMutexError(nullptr);
}
static std::string myName() {
@ -287,7 +295,8 @@ private:
"- useless calls of string and STL functions\n"
"- dereferencing an invalid iterator\n"
"- reading from empty STL container\n"
"- consider using an STL algorithm instead of raw loop\n";
"- consider using an STL algorithm instead of raw loop\n"
"- incorrect locking with mutex\n";
}
};
/// @}

16
lib/token.cpp
View File

@ -2086,6 +2086,8 @@ const ::Type *Token::typeOf(const Token *tok)
std::pair<const Token*, const Token*> Token::typeDecl(const Token * tok)
{
if (!tok)
return {};
if (Token::simpleMatch(tok, "return")) {
const Scope *scope = tok->scope();
if (!scope)
@ -2102,9 +2104,19 @@ std::pair<const Token*, const Token*> Token::typeDecl(const Token * tok)
return {};
if (!var->typeStartToken() || !var->typeEndToken())
return {};
if (Token::simpleMatch(var->typeStartToken(), "auto")) {
const Token * tok2 = var->declEndToken();
if (Token::Match(tok2, "; %varid% =", var->declarationId()))
tok2 = tok2->tokAt(2);
if (Token::simpleMatch(tok2, "=") && tok2->astOperand2()) {
std::pair<const Token*, const Token*> r = typeDecl(tok2->astOperand2());
if (r.first)
return r;
}
}
return {var->typeStartToken(), var->typeEndToken()->next()};
} else if (Token::Match(tok, "%name%")) {
const Function *function = tok->function();
} else if (Token::Match(tok->previous(), "%name% (")) {
const Function *function = tok->previous()->function();
if (!function)
return {};
return {function->retDef, function->returnDefEnd()};

3
test/testautovariables.cpp
View File

@ -1986,8 +1986,9 @@ private:
" return get_default(m, k, &x);\n"
"}\n",
true);
ASSERT_EQUALS(
TODO_ASSERT_EQUALS(
"[test.cpp:9] -> [test.cpp:9] -> [test.cpp:8] -> [test.cpp:9]: (error, inconclusive) Returning pointer to local variable 'x' that will be invalid when returning.\n",
"",
errout.str());
check("std::vector<int> g();\n"

113
test/teststl.cpp
View File

@ -165,6 +165,8 @@ private:
TEST_CASE(invalidContainer);
TEST_CASE(invalidContainerLoop);
TEST_CASE(findInsert);
TEST_CASE(checkMutexes);
}
void check(const char code[], const bool inconclusive=false, const Standards::cppstd_t cppstandard=Standards::CPPLatest) {
@ -4411,6 +4413,117 @@ private:
true);
ASSERT_EQUALS("", errout.str());
}
void checkMutexes() {
check("void f() {\n"
" static std::mutex m;\n"
" static std::lock_guard<std::mutex> g(m);\n"
"}\n",
true);
ASSERT_EQUALS("[test.cpp:3]: (warning) Lock guard is defined globally. Lock guards are intended to be local. A global lock guard could lead to a deadlock since it won't unlock until the end of the program.\n", errout.str());
check("void f() {\n"
" static std::mutex m;\n"
" std::lock_guard<std::mutex> g(m);\n"
"}\n",
true);
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" std::mutex m;\n"
" std::lock_guard<std::mutex> g(m);\n"
"}\n",
true);
ASSERT_EQUALS("[test.cpp:3]: (warning) The lock is ineffective because the mutex is locked at the same scope as the mutex itself.\n", errout.str());
check("void g();\n"
"void f() {\n"
" static std::mutex m;\n"
" m.lock();\n"
" g();\n"
" m.unlock();\n"
"}\n",
true);
ASSERT_EQUALS("", errout.str());
check("void g();\n"
"void f() {\n"
" std::mutex m;\n"
" m.lock();\n"
" g();\n"
" m.unlock();\n"
"}\n",
true);
ASSERT_EQUALS("[test.cpp:4]: (warning) The lock is ineffective because the mutex is locked at the same scope as the mutex itself.\n", errout.str());
check("class A {\n"
" std::mutex m;\n"
" void f() {\n"
" std::lock_guard<std::mutex> g(m);\n"
" }\n"
"};\n",
true);
ASSERT_EQUALS("", errout.str());
check("class A {\n"
" std::mutex m;\n"
" void g();\n"
" void f() {\n"
" m.lock();\n"
" g();\n"
" m.unlock();\n"
" }\n"
"};\n",
true);
ASSERT_EQUALS("", errout.str());
check("class A {\n"
" std::mutex m;\n"
" void f() {\n"
" static std::lock_guard<std::mutex> g(m);\n"
" }\n"
"};\n",
true);
ASSERT_EQUALS("[test.cpp:4]: (warning) Lock guard is defined globally. Lock guards are intended to be local. A global lock guard could lead to a deadlock since it won't unlock until the end of the program.\n", errout.str());
check("std::mutex& h();\n"
"void f() {\n"
" auto& m = h();\n"
" std::lock_guard<std::mutex> g(m);\n"
"}\n",
true);
ASSERT_EQUALS("", errout.str());
check("void g();\n"
"std::mutex& h();\n"
"void f() {\n"
" auto& m = h();\n"
" m.lock();\n"
" g();\n"
" m.unlock();\n"
"}\n",
true);
ASSERT_EQUALS("", errout.str());
check("std::mutex& h();\n"
"void f() {\n"
" auto m = h();\n"
" std::lock_guard<std::mutex> g(m);\n"
"}\n",
true);
ASSERT_EQUALS("[test.cpp:4]: (warning) The lock is ineffective because the mutex is locked at the same scope as the mutex itself.\n", errout.str());
check("void g();\n"
"std::mutex& h();\n"
"void f() {\n"
" auto m = h();\n"
" m.lock();\n"
" g();\n"
" m.unlock();\n"
"}\n",
true);
ASSERT_EQUALS("[test.cpp:5]: (warning) The lock is ineffective because the mutex is locked at the same scope as the mutex itself.\n", errout.str());
}
};
REGISTER_TEST(TestStl)