Re: Openssl Memory leak

[Nikos Balkanas]

70 KB is nothing nowadays. Besides each thread has its memory requirements, and 
memory is supposed to increase the more threads you use. Even if the threads 
reduce (lower load) memory may not go all the way back, because of global 
structures that have grown due to the load. But after several cycles, memory 
should stabilize when releasing threads.

Best way is to put it through valgrind, but I expect that this is already been 
done by the developers in the group.

BR,
Nikos
  ----- Original Message ----- 
  From: Fabian Bergmark 
  To: openssl-users@openssl.org 
  Sent: Thursday, May 07, 2009 4:49 PM
  Subject: Re: Openssl Memory leak


  After some investigation I've figured out that the memory leak isn't caused 
by running Openssl in threads. However, after about 200 connections, may vary, 
the used memory increases with around 70 kb. Is this normal? I guessed it's 
allocated by the openssl library


  2009/5/6 Fabian Bergmark <fabian.bergm...@gmail.com>

    Okey. Now i got no more memory leaks when I put the SSL code in main. 
However, if i try to put the exact same code in a thread the memory leak is 
back.

    Here is the essential code I'm using;

    void lcserver::start()
    {
    SSL_library_init();
    SSL_load_error_strings();
    method = SSLv23_server_method();
    ctx = SSL_CTX_new(method);

    Some windows socket code...

    while(acceptsocket = accept(listensocket,(sockaddr*)&sin,&len))
    {
    struct clientinfo *client;
    client = new struct 
clientinfo(acceptsocket,sin.sin_addr.s_addr,clientid++,this,rooms[0]->getthis(),ctx);
    client->M1();
    }
    }

    void clientinfo::M1()
    {
    CreateThread(0,0,(LPTHREAD_START_ROUTINE)M2,(LPVOID)this,0,0);
    }

    void clientinfo::M2(LPVOID param)
    {
        clientinfo* Call = (clientinfo*)param;
        Call->listenfor();
        delete Call;
        return;
    }

    void clientinfo::listenfor()

    {
    SSL_set_bio(ssl,bio,bio);
    SSL_accept(ssl);

    while(SSL_shutdown(ssl) == 0)
    ;
    SSL_free(ssl);
    ERR_remove_state(0);
    }

    Just running this code which shouldn't leave any allocated memory, about 12 
kb ram is still allocated. 



    2009/5/5 Nikos Balkanas <nbalka...@gmail.com>


      Hi,

      Check the return value of SSL_shutdown(ssl). Sometimes it needs up to 4 
iterations to complete due to internal state machine. It completes when the 
value != 0. Hope it helps.

      BR,
      Nikos
        ----- Original Message ----- 
        From: Fabian Bergmark 
        To: openssl-users@openssl.org 
        Sent: Tuesday, May 05, 2009 9:13 PM
        Subject: Openssl Memory leak


        Hi

        I am currently writing a Chat application using the Openssl library for 
encryption. It's a multi-thread application and every client is managed by a 
different thread.
        However, ever since I implemented Openssl there seams to be a memory 
leak of around 10 kb.
        My openssl-code code is looking like following:

        SSL_set_bio(ssl,bio,bio);
        SSL_accept(ssl);
        SSL_shutdown(ssl);
        SSL_free(ssl);

        where bio and ssl is class objects where BIO is set like

        bio = BIO_new_socket(s,BIO_NOCLOSE)

        The increased memory does not occur before SSL_accept(ssl). The first 
time a client connect about a 100 kb is allocated, which I suppose is due to 
some initialising function. For each new client about 0-20 kb are still 
allocated after 

        SSL_shutdown(ssl);
        SSL_free(ssl);

        is issued. Is there some cleanup functions im forgetting?

        I am using windows btw.