Revert "Avoid duplication."

This reverts commit d480e182.

Commit broke TLS handshakes due to fragility of digest caching: that will be
fixed separately.
Reviewed-by: NRich Salz <rsalz@openssl.org>

ssl/s3_enc.c

@@ -476,21 +476,15 @@ void ssl3_cleanup_key_block(SSL *s)
 
 void ssl3_init_finished_mac(SSL *s)
 {
+    BIO_free(s->s3->handshake_buffer);
     ssl3_free_digest_list(s);
     s->s3->handshake_buffer = BIO_new(BIO_s_mem());
     (void)BIO_set_close(s->s3->handshake_buffer, BIO_CLOSE);
 }
 
-/*
- * Free digest list. Also frees handshake buffer since they are always freed
- * together.
- */
-
 void ssl3_free_digest_list(SSL *s)
 {
     int i;
-    BIO_free(s->s3->handshake_buffer);
-    s->s3->handshake_buffer = NULL;
     if (!s->s3->handshake_dgst)
         return;
     for (i = 0; i < SSL_MAX_DIGEST; i++) {

ssl/s3_lib.c

@@ -2905,6 +2905,7 @@ void ssl3_free(SSL *s)
     OPENSSL_free(s->s3->tmp.ciphers_raw);
     OPENSSL_clear_free(s->s3->tmp.pms, s->s3->tmp.pmslen);
     OPENSSL_free(s->s3->tmp.peer_sigalgs);
+    BIO_free(s->s3->handshake_buffer);
     ssl3_free_digest_list(s);
     OPENSSL_free(s->s3->alpn_selected);
 
@@ -2939,6 +2940,8 @@ void ssl3_clear(SSL *s)
 #endif                         /* !OPENSSL_NO_EC */
 
     init_extra = s->s3->init_extra;
+    BIO_free(s->s3->handshake_buffer);
+    s->s3->handshake_buffer = NULL;
     ssl3_free_digest_list(s);
 
     if (s->s3->alpn_selected) {