Test mbedtls_rsa_gen_key() with NULL ctx/RNG separately
diff --git a/tests/suites/test_suite_rsa.function b/tests/suites/test_suite_rsa.function
index 2da01ef..60c13c8 100644
--- a/tests/suites/test_suite_rsa.function
+++ b/tests/suites/test_suite_rsa.function
@@ -67,7 +67,11 @@
                                                  invalid_padding, 0 ) );
 
     TEST_INVALID_PARAM_RET( MBEDTLS_ERR_RSA_BAD_INPUT_DATA,
-                            mbedtls_rsa_gen_key( NULL, NULL, NULL, 0, 0 ) );
+                            mbedtls_rsa_gen_key( NULL, rnd_std_rand,
+                                                 NULL, 0, 0 ) );
+    TEST_INVALID_PARAM_RET( MBEDTLS_ERR_RSA_BAD_INPUT_DATA,
+                            mbedtls_rsa_gen_key( &ctx, NULL,
+                                                 NULL, 0, 0 ) );
 
     TEST_INVALID_PARAM_RET( MBEDTLS_ERR_RSA_BAD_INPUT_DATA,
                             mbedtls_rsa_check_pubkey( NULL ) );