diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index bb74c26..fbc5949 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -1461,6 +1461,7 @@
 
 psa_status_t psa_cipher_finish(psa_cipher_operation_t *operation,
                                uint8_t *output,
+                               size_t output_size,
                                size_t *output_length)
 {
     int ret = MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;