Question

Hi I am getting a Run time Error saying that the stack around szDeviceType is corrupted but I have no idea, i’m very new to c++ so I wouldn’t have the most knowledge. Any help would greatly be appreciated.

HRESULT hr = S_OK;
UINT er = ERROR_SUCCESS;
int szDeviceType = 0;
char lpszString[MAX_PATH];
LPWSTR szComport = NULL;
LPWSTR szNumChannels = NULL;
char szChannels[MAX_PATH];
char szPort[MAX_PATH];

hr = WcaInitialize(hInstall, "GetDatascanInfo");
ExitOnFailure(hr, "Failed to initialize");

WcaLog(LOGMSG_STANDARD, "Initialized.");

hr = WcaGetIntProperty(L"DEVICETYPE",&szDeviceType);
ExitOnFailure(hr, "failed to get Device Type");

hr = WcaGetFormattedProperty(L"COMPORT",&szComport);
ExitOnFailure(hr, "failed to get Com Port");

wcstombs(szPort, szComport, 500);

hr = WcaGetProperty(L"NUMCHANNELS",&szNumChannels);
ExitOnFailure(hr, "failed to get Com Port");

wcstombs(szChannels, szNumChannels, 500);

    if(szDeviceType == 2)
    {
        strcat(lpszString, "datascan");
        strcat(lpszString, szPort);
        strcat(lpszString, "DATASCAN 7000,DS:");
        strcat(lpszString, szChannels);

    }
    if (szDeviceType == 3)
    {
        strcat(lpszString, "solo");
        strcat(lpszString, szPort);
        strcat(lpszString, "DATASCAN SOLO,SA:");
        strcat(lpszString, szChannels);

    }
    if (szDeviceType == 4)
    {
        strcat(lpszString, "dataweb");
        strcat(lpszString, szPort);
        strcat(lpszString, "DATAWEB,DW:");
        strcat(lpszString, szChannels);
    }

    hr = MsiSetProperty(hInstall, "DATASCANINFO",  lpszString);
    ExitOnFailure(hr, "failed to set DATASCANINFO");


LExit:
er = SUCCEEDED(hr) ? ERROR_SUCCESS : ERROR_INSTALL_FAILURE;
return WcaFinalize(er);
}

Answer 1

This looks suss:

wcstombs(szPort, szComport, 500);

The last parameter is the maximum number of characters to write, but your array is only MAX_PATH in size which is 260.

You’re also using strcat to append to lpszString without checking whether that overflows. You should probably switch to using strcat_s which has bounds checking.