Bug #107692 connector xapi call mysqlx_session_close crash when network is disconnect

• Submitted: 29 Jun 2022 2:43
• Modified: 4 Aug 2023 10:13
• Reporter: bingo yang
• Status: Closed
• Category: Connector / C++
• Severity: S2 (Serious)
• Version: 8.0.33
• OS: Windows
• CPU Architecture: Any

[29 Jun 2022 2:43] bingo yang

Description:
Connector/C++ 8.0.29 call mysqlx_session_close crash when network is disconnect

Steps:

I download Connector/C++ 8.0.29 From thi page https://dev.mysql.com/downloads/connector/cpp/

using vs 2017 construct a resolution.

1. First create a session using mysqlx_get_session_from_options.
The mysql server and the client are in different machine,

2. make the client disconnect the Internet

3. call mysqlx_session_close: the application will crash; try cach is not work

How to repeat:
int MysqlApiTest::cTest()
{
std::string MysqlApiTest::mUser = "root";
std::string MysqlApiTest::mPwd = "toot";
std::string MysqlApiTest::mIp = "10.3.68.8";
int MysqlApiTest::mPort = 33060;// 33060;//6448
std::string MysqlApiTest::mDbName = "db_test";

    mysqlx_session_t  *sess = NULL;
    std::string mCurErrcode;

    mysqlx_session_options_t *opt = NULL;
    mysqlx_error_t *error = NULL;
    opt = mysqlx_session_options_new();

    int optRes = mysqlx_session_option_set(opt,
        OPT_HOST(mIp.c_str()), OPT_PORT(mPort),
        OPT_USER(mUser.c_str()), OPT_PWD(mPwd.c_str()),
        OPT_DB(mDbName.c_str()),
        OPT_SSL_MODE(SSL_MODE_DISABLED),
        OPT_COMPRESSION(MYSQLX_COMPRESSION_DISABLED),
        PARAM_END);

    sess = mysqlx_get_session_from_options(opt, &error);
    mysqlx_free(opt);

    if (sess == NULL)
    {
        mCurErrcode = mysqlx_error_num(error);  //if option error, mCurErrcode = 0
        std::string str(mysqlx_error_message(error));
        mysqlx_free(error);
        return 1;
    }
    printf("\nSession create");
    if (error != NULL) {
        mysqlx_free(error);
        error = NULL;
    }

    try {
        mysqlx_session_close(sess);
    }
    catch (const ::mysqlx::Error&) { }   
    catch (const std::out_of_range&) { } 
    catch (const std::exception &e) 
    {
        throw;
        return 0;
    }
    catch (const char *e) 
    {} 
    catch (...) 
    {}

    return 0;
}

Suggested fix:
the exception is throwed in mysql-connector-cpp-8.0.29\cdk\mysqlx\session.cc void Session::close().

The try catch in mysqlx.cc (void STDCALL mysqlx_session_close(mysqlx_session_struct *sess)) seemed not work

[30 Jun 2022 16:09] MySQL Verification Team

Hello,

Thank you for the bug report and feedback.

Regards,
Ashwini Patil

[1 Aug 2022 16:48] Christine Cole

Posted by developer:
 
Fixed as of the upcoming MySQL Connector/C++ 8.0.31 release, and here's the proposed changelog entry from the documentation team:

If an application program called mysqlx_session_close after disconnecting
from the Internet, an exception from Connector/C++ could cause the
application to halt unexpectedly.

Thank you for the bug report.

[14 Jul 2023 8:26] bingo yang

I have tested the bug using mysql server 8.0.31 without router and connetor 8.0.31/32 both using c version api. It still cause crash. Cloud you please check it in again? thanks

[4 Aug 2023 10:13] bingo yang

8.0.33 connector + 8.0.31 mysql server:  when created the session without OPENSSL  "OPT_SSL_MODE(SSL_MODE_DISABLED)", it will crash. if enable OPENSSL  ,wont't crash.