Fix leak in ERR_get_state() when OPENSSL_init_crypto() isn't called yet
If OPENSSL_init_crypto() hasn't been called yet when ERR_get_state() is called, it need to be called early, so the base initialization is done. On some platforms (those who support DSO functionality and don't define OPENSSL_USE_NODELETE), that includes a call of ERR_set_mark(), which calls this function again. Furthermore, we know that ossl_init_thread_start(), which is called later in ERR_get_state(), calls OPENSSL_init_crypto(0, NULL), except that's too late. Here's what happens without an early call of OPENSSL_init_crypto(): => ERR_get_state(): => CRYPTO_THREAD_get_local(): <= NULL; # no state is found, so it gets allocated. => ossl_init_thread_start(): => OPENSSL_init_crypto(): # Here, base_inited is set to 1 # before ERR_set_mark() call => ERR_set_mark(): => ERR_get_state(): => CRYPTO_THREAD_get_local(): <= NULL; # no state is found, so it gets allocated!!!!! => ossl_init_thread_start(): => OPENSSL_init_crypto(): # base_inited is 1, # so no more init to be done <= 1 <= => CRYPTO_thread_set_local(): <= <= <= <= 1 <= => CRYPTO_thread_set_local() # previous value removed! <= Result: double allocation, and we have a leak. By calling the base OPENSSL_init_crypto() early, we get this instead: => ERR_get_state(): => OPENSSL_init_crypto(): # Here, base_inited is set to 1 # before ERR_set_mark() call => ERR_set_mark(): => ERR_get_state(): => OPENSSL_init_crypto(): # base_inited is 1, # so no more init to be done <= 1 => CRYPTO_THREAD_get_local(): <= NULL; # no state is found, so it gets allocated # let's assume we got 0xDEADBEEF => ossl_init_thread_start(): => OPENSSL_init_crypto(): # base_inited is 1, # so no more init to be done <= 1 <= 1 => CRYPTO_thread_set_local(): <= <= <= <= 1 => CRYPTO_THREAD_get_local(): <= 0xDEADBEEF <= 0xDEADBEEF Result: no leak. Reviewed-by: Rich Salz <rsalz@openssl.org> (Merged from https://github.com/openssl/openssl/pull/4913)
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