Commit Graph

170 Commits

Author SHA1 Message Date
Paul Fultz II 507c7a4388 Improvement to lifetime tracking of addressof and derefencing
This will now warn for cases like this:

```cpp
auto& f() {
    std::vector<int> x;
    return x[0];
}
```

It also improves the handling of address of operator, so it can now warn across some function calls, like this:

```cpp
int& f(int& a) {
    return a;
}
int* hello() {
    int x = 0;
    return &f(x);
}
```
2019-02-22 06:38:56 +01:00
Paul Fultz II 715714f4de Forward lifetimes in "for" loops (#1682)
* Forward lifetimes in for loops

* Format
2019-02-22 06:37:02 +01:00
Kamil Dudka 2908593cf6 checkautovariables: eliminate false positives on assignment of &ptr->item (#1667)
Even if `ptr` is a local variable, the object `ptr->item` might be not.
So taking address of `ptr->item` is definitely not unsafe in general.

This commit fixes false positives triggered by commit
1.85-249-gf42648fe2 on the following code of sssd:

https://github.com/SSSD/sssd/blob/d409df33/src/sbus/request/sbus_request.c#L359
2019-02-18 09:35:07 +01:00
Daniel Marjamäki bd7790fd8c Update copyright year 2019-02-09 07:24:06 +01:00
Paul Fultz II c176775afb Avoid infinite recursion in getLifetimeVariable (#1634)
* Fix direct recursion

* Limit depth of getLifetimeVariable
2019-01-31 10:34:41 +01:00
Paul Fultz II 165a22ed0f Lifetime: Support analysis with functions that do not return a reference (#1632)
* Initial support for function return

* Add test case

* Add support for reference parameters

* Format
2019-01-29 09:47:52 +01:00
Paul Fultz II d6aaf401df Lifetime: Follow functions that return references
This will now warn for cases like this:

```cpp
int& f(int& a) {
    return a;
}
int& hello() {
    int x = 0;
    return f(x);
}
```
2019-01-26 11:03:57 +01:00
Paul Fultz II 3975913637 Extend lifetime checking for references
This will use the lifetime checker for dangling references. It will find these cases for indirectly assigned reference:

```cpp
int &foo()
{
    int s = 0;
    int& x = s;
    return x;
}
```

This will also fix issue 510 as well:

```cpp
int &f( int k )
{
    static int &r = k;
    return r;
}
```
2019-01-23 07:29:16 +01:00
Daniel Marjamäki 8dd641b8be Use OVERRIDE in test 2019-01-12 15:45:25 +01:00
Paul Fultz II 921f6e4313 Fix issue 8883: False positive: returnDanglingLifetime with local struct or class (#1585) 2019-01-11 09:51:02 +01:00
practicalswift 0a1b3a9d6f Fix typos (#1568) 2019-01-06 17:15:57 +01:00
Paul Fultz II e4677ae640 Fix issue 8910: Regression: ValueFlow: wrong conditional tokvalue
This fixes issue in:

```cpp
void f()
{
    char stack[512];
    RGNDATA *data;

    if (data_size > sizeof (stack))
        data = malloc (data_size);
    else
        data = (RGNDATA *)stack;

    if ((char *)data != stack)
            free (data); // <- data is not stack
}
```

It seems the `ProgramMemory` can't handle two known values(such as int and tok) together. So instead `ValueFlowAfterAssign` runs `ValueFlowForward` with tok values and then runs it with the other values.
2018-12-29 09:31:21 +01:00
Paul Fultz II 45dcfad9f9 Fix issue 8899: False positive returnDanglingLifetime when returning by value
This fixes the FP from:

```cpp
#include <string>

class MyString
{
        public:
        MyString(char* source)
        {
                length = strlen( source );
                buffer = new char[length+1];
                if( buffer )
                {
                        strcpy( buffer, source );
                }
        }

        char* buffer;
        int length;
};

MyString Foo()
{
        char arr[20];
        sprintf(arr, "hello world");

        return arr;
}

void main()
{
        MyString str = Foo();

        printf(str.buffer);
}
```
2018-12-15 17:58:45 +01:00
Paul Fultz II 3e1b34dd8f Fix FPs and crashes with byDerefCopy (#1503)
* Fix FP when inserting a range into a container

* Formatting

* Fix crash
2018-12-02 14:31:31 +01:00
Daniel Marjamäki ccbaad32f9 Fix merge conflicts 2018-12-01 19:14:43 +01:00
Paul Fultz II b841b818d2 Fix 8872: Crash in LifetimeStore when there is no scope for variable
This fixes crash in:

```cpp
struct edit_line_paste_over {
    void operator()(agi::Context *c) override {
        paste_lines(c, true, [&](AssDialogue *new_line) -> AssDialogue * {
            AssDialogue *ret = paste_over(c->parent, pasteOverOptions, new_line, static_cast<AssDialogue*>(&*pos));
            return ret;
          });
    }
};
```
2018-12-01 19:11:26 +01:00
Paul Fultz II 67dd822910 Fix FP in lifetime anlaysis: Dont decay std array
This will fix FP with:

```cpp
std::array<char, 1> f() {
    std::array<char, 1> x;
    return x;
}
```
2018-12-01 19:09:19 +01:00
Paul Fultz II 229c45e7f8 Fix issue 8865: FP with dangling lifetime
This fixes:

```cpp
void f(uint32_t event, unsigned long op, const xen_ulong_t *args)
{
    struct __packed {
        uint32_t op;
        uint32_t args[6];
    } d;
    uint32_t *a = d.args;
}
```
2018-12-01 19:07:46 +01:00
Daniel Marjamäki f42648fe22 Fixed #8114 (false positive: Address of local auto-variable assigned to a function parameter.) 2018-12-01 10:11:02 +01:00
Paul Fultz II f16d9d7d90 Issue 6175: Check lifetime of a variables stored in containers and member variables
Cppcheck will now warn for all cases here:

```cpp
#include <vector>
class CCluster {};
class MyClass
{ public:
    std::vector<CCluster*> m_cluster;
    void createCluster()
    {
        CCluster cl;
        CCluster* pcl=&cl;
        m_cluster.push_back(pcl);
    }
    void createCluster2()
    {
        CCluster cl;
        m_cluster.push_back(&cl);
    }
    CCluster* Cluster()
    {
        CCluster cl;
        CCluster* pcl=&cl;
        return pcl;
    }
    CCluster* Cluster2()
    {
        CCluster cl;
        return &cl;
    }
};

```
2018-11-21 08:43:57 +01:00
Paul Fultz II 7ef119cbfc Fix FPs in lifetime checker
This fixes several FPs in the lifetime checker. It also fixes issue [8846](https://trac.cppcheck.net/ticket/8846):

```cpp
int * f(int a[])
{
        return a;
}
```
2018-11-17 09:41:59 +01:00
Paul Fultz II d376e9f245 Track variable lifetime through function calls (#1481) 2018-11-16 06:12:28 +01:00
Paul Fultz II 54453c5802 Fix FP when copying pointer to string (#1479) 2018-11-14 06:59:25 +01:00
Paul Fultz II 0e11bb07c8 Extend lifetime analysis to pointer usage (#1477)
* Use lifetime analysis for pointers as well

* Fix issue 1143: Pointer to local array

* Update message when using pointers

* Avoid infinite loop in tracing lifetimes
2018-11-12 10:08:17 +01:00
Paul Fultz II 68d6b96878 Diagnose invalid lifetimes (#1475)
* Add check for invalid lifetimes

* Fix FP with member variables

* Dont forward lifetime values in subfunction

* Update message to use out of scope
2018-11-11 16:43:54 +01:00
Daniel Marjamäki ee2dfb6604 Fixed #8058 (False positive returnAddressOfAutoVariable within lambda) 2018-11-11 07:52:38 +01:00
Paul Fultz II 1ffcc6b730 Add initial lifetime checker (#1448)
* Inital valueflow lifetime checker

* Forward values

* Add initial tests

* Fix deplicate messages

* Fix traversing nested lambdas

* Turn test case into a todo

* Skip if returning a container

* Fix FP when using references

* Add missing header

* Fix FP from broken scopes

* Fix FP with static variable

* Add test for more FPs

* Parse lambda functions

* Check for capture by value

* Add tests for using a container and lambda together

* Fix cppcheck errors

* Add test for nextAfterAstRightmostLeaf

* Add valueflow tests

* Update error message

* Check for correct lambda token

* Improve error path reporting

* Fix hang when parsing arrays that look almlost like lambdas
2018-11-10 16:40:40 +01:00
Daniel Marjamäki 66ca03fa0c Fixed #8826 (false negative: Invalid memory address freed) 2018-11-03 18:55:20 +01:00
Paul Fultz II fa40b821e6 Fix issue 8740: Add a pass to check for valid operators (#1372) 2018-09-08 21:10:34 +02:00
Daniel Marjamäki 43233e72b2 Fixed #8691 (False negative for uselessAssignmentArg) 2018-08-17 19:56:36 +02:00
Daniel Marjamäki cde63c7573 Use Variable::valueType instead of Variable::typeStartToken in auto variables 2018-06-24 08:25:19 +02:00
IOBYTE ce50df8047 Fix override warnings. (#1234) 2018-05-15 16:37:40 +02:00
Daniel Marjamäki 7e4dba6a7e Updated copyright year 2018-03-31 20:59:09 +02:00
Daniel Marjamäki c110770481 Fixed #8325 (False negative: address of auto variable being returned when assigned to another variable first) 2018-01-27 14:48:45 +01:00
Daniel Marjamäki cb297a00fc Auto variables: Assign address of local variable to global pointer (#6825) 2018-01-25 22:50:41 +01:00
Daniel Marjamäki 599e038282 AutoVariables: Warn when address of local array is assigned to global pointer and pointer is not reassigned 2018-01-24 21:33:58 +01:00
Daniel Marjamäki c4caee6b18 Updated copyright year 2018-01-14 15:37:52 +01:00
Ayaz Salikhov 28aa939d69 iwyu - include what you use 2017-05-27 04:33:47 +02:00
Daniel Marjamäki f68fa72095 Fixed #7583 (Defect: False positive '(error) Reference to temporary returned') 2017-02-26 13:41:49 +01:00
PKEuS ea53bd22b7 Fixed false positive returnTempReference with operator++ (#7874) 2016-12-22 11:49:59 +01:00
Daniel Marjamäki aaf19c1e4f Fixed #7839 (Prefix increment triggers parameter modification warning) 2016-12-19 15:25:36 +01:00
PKEuS 1715969f6f Support prefix-increment/decrement in CheckAutoVariables::assignFunctionArg() (#3177) 2016-10-10 21:34:40 +02:00
Alexander Mai d492500f34 #5844 False positive: returnReference fp for inner lambda function 2016-05-20 23:46:56 +02:00
PKEuS 23ad881c64 Fixed false positive returnLocalVariable (#7180) 2016-01-30 20:18:12 +01:00
Lauri Nurmi 996c9244d8 Update copyright year to 2007-2016. 2016-01-01 15:34:45 +02:00
Alexander Mai ba0859e838 #6981 crash in checkvaarg.cpp (with possible fix). Avoid segfault. Add SymbolDatabase::validate() to allow validating smyboldatabase 2015-12-05 20:55:26 +01:00
Daniel Marjamäki 0f9d90d2be Changed Copyrights. Removed my name. 2015-11-18 20:04:50 +01:00
Daniel Marjamäki 71bf0f076f CheckAutoVariables: Handle 'x-y' better in isAutoVarArray 2015-11-15 19:34:36 +01:00
Daniel Marjamäki 4e578af603 CheckAutoVar: Improved usage of AST and ValueFlow 2015-11-15 14:48:13 +01:00
Daniel Marjamäki c10a10c26f CheckAutoVariables: use ValueFlow to detect more errors when pointer aliases are used 2015-11-15 12:10:35 +01:00