diff --git a/ssl/ssl_sess.c b/ssl/ssl_sess.c
index d30a24f2f..ee88be2b8 100644
--- a/ssl/ssl_sess.c
+++ b/ssl/ssl_sess.c
@@ -320,10 +320,12 @@ int ssl_get_prev_session(SSL *s, unsigned char *session_id, int len,
 		fatal = 1;
  		goto err;
 		}
-	else if (r == 0)
+	else if (r == 0 || (!ret && !len))
 		goto err;
 	else if (!ret && !(s->session_ctx->session_cache_mode & SSL_SESS_CACHE_NO_INTERNAL_LOOKUP))
 #else
+	if (len == 0)
+		goto err;
 	if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_NO_INTERNAL_LOOKUP))
 #endif
 		{