Regression in 1.1.1 against 1.1.0 in SSL_CTX_new

[Harald Koch]

Hello list,

I have a TLS server which is started on demand in a multithreaded (pthread) application. The TLS server is one thread which is being started and stopped. At first start, the TLS server initialized with SSL_CTX_new with TLS_server_method works as expected, after cleaning up, eliminating the thread and starting it again at a later time in the same process, SSL_CTX_new returns NULL. I’ve been digging deeper into the initialization code, and found out that in crypto/threads_pthread.c, function CRYPTO_THREAD_set_local the call to pthread_setspecific returns a value != 0 (in my case: 22). The error queue of openSSL stays empty. The same code works with openSSL 1.1.0 in all versions.
Some posts googled state that before usage, be sure to run OPENSSL_init_ssl (which I do, even if not required to my analysis since it’s already called in one of the called functions deeper in the library).
Am I missing something in a multithreaded environment?

Regards,
Harald