Use OPENSSL_clear_free()

Author: RaisinTen

src/crypto/crypto_dh.cc

@@ -578,13 +578,16 @@ Local<Value> StatelessDiffieHellman(
                                            &out_size))
     return Undefined(env->isolate());
 
+  void* hint = reinterpret_cast<void*>(static_cast<uintptr_t>(out_size));
   return Buffer::New(env,
                      buf,
                      out_size,
                      [](char* data, void* hint) {
-                       OPENSSL_free(data);
+                       size_t out_size = static_cast<size_t>(
+                           reinterpret_cast<uintptr_t>(hint));
+                       OPENSSL_clear_free(data, out_size);
                      },
-                     nullptr).FromMaybe(Local<Object>());
+                     hint).FromMaybe(Local<Object>());
 }
 
 // The version of StatelessDiffieHellman that returns a Buffer