OPENSSL_init_crypto with OPENSSL_INIT_NO_ATEXIT issue

[Dan Heinz <dheinz@xxxxxxxxxxxxxxx>]

I have a static library using OpenSSL (built as static library with the no-pinshared parameter in the configuration) that is then included in a DLL that gets loaded and unloaded many times by the calling application.  Now that the code is in 1.1.1c to allow me to manually shutdown the OpenSSL library, I’ve run into an issue when loading and unloading my DLL multiple times from the calling application.  I am testing this on Windows 10.  A summary of what I am doing:

1. Calling executable calls LoadLibrary to load the DLL containing the static library that uses OpenSSL.
2. Calling executable calls a function of the now loaded DLL.
3. The DLL function calls a function in the static library to initialize OpenSSL using: openssl_result = OPENSSL_init_crypto(OPENSSL_INIT_NO_ATEXIT, NULL);
4. The DLL function calls a function in the static library to decrypt some data using the RSA_private_decrypt OpenSSL API.
5. The DLL function calls a function in the static library to shutdown OpenSSL using: OPENSSL_cleanup(); (required)  and CRYPTO_cleanup_all_ex_data(); (not sure if this is needed).
6. The calling executable uses FreeLibrary to unload the DLL.
7. The calling executable goes to step 1 to  repeat the process.

Iterating through the above steps always fails on iteration 1077.  OpenSLL reports the error:
error:4088003:rsa routines:RSA_setup_binding:BN lib

 

After some debugging, I see that the failure happens in the function CRYPTO_THREAD_init_local in threads_win.c.  *key = TlsAlloc(); fails with the error TLS_OUT_OF_INDEXES.

 

Is something not being freed? Is there something additional I need to do at shutdown?