Date: Fri, 14 Aug 1998 18:50:02 +0200
From: Jochen Wiedmann 
Subject: mysql: Connecting/Disconnecting 1100 times freezes server

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        for mysql@tcx.se; Fri, 14 Aug 1998 18:42:55 +0200
Date: Fri, 14 Aug 1998 18:42:55 +0200
Full-Name: root
Message-Id: <199808141642.SAA08052@laptop.ispsoft.de>
From: joe
To: mysql@tcx.se
Subject: connecting/disconnecting 1100 times freezes server

>Description:

        A simple test script that connects/disconnects in an endless
        loop makes the MySQL server freeze after approximately 1100
        iterations.

        Is this a bug or a security related feature? If the latter,
        can I turn it off somehow, as it prevents me from
        investigating a memory leak in the DBD::mysql's connect
        method.

>How-To-Repeat:

        #include 
        #include 
        #include 
        #include 

        int main(int argc, char* argv[]) {
            MYSQL sock;
            int i = 0;

            while (1) {
                if (++i % 100 == 0) {
                    printf("%d\n", i);
                }
                mysql_init(&sock);
                if (!mysql_real_connect(&sock, NULL, NULL, NULL, NULL,
                                        0, NULL, 0)) {
                    fprintf(stderr, "Cannot connect: %s\n",
                            mysql_error(&sock));
                    exit(10);
                }
                mysql_close(&sock);
            }
        }

>Fix:
        Not known


---------- Forwarded message ----------
From: Adam Ipnarski 
To: BUGTRAQ@netspace.org
Date: Sat, 15 Aug 1998 12:02:36 +0000
Subject: Re: MySQL DoS?

> >Description:
>
>         A simple test script that connects/disconnects in an endless
>         loop makes the MySQL server freeze after approximately 1100
>         iterations.


I have tried this on MySQL v9.15, dist.3.21.30 for Solaris.  After
changing a few calls (different arguments for mysql_real_connect, and no
mysql_init), it stayed up perfectly for over 30,000 connects.  This
would seem to suggest that the problem is only in the new connect call
for dist >= 3.22.00.

--
Adam Wielowieyski-Ipnarski
adam@fastfare.co.uk | www.travelselect.com