diff --git a/src/log.c b/src/log.c
index 5c42f6b2a..520263a71 100644
--- a/src/log.c
+++ b/src/log.c
@@ -484,6 +484,8 @@ int add_sample_to_logformat_list(char *text, char *arg, int arg_len, struct prox
 		node->options |= LOG_OPT_RES_CAP; /* fetch method is response-compatible */
 
 	if (!(expr->fetch->val & cap)) {
+		free(node);
+		node = NULL;
 		memprintf(err, "sample fetch <%s> may not be reliably used here because it needs '%s' which is not available here",
 		          text, sample_src_names(expr->fetch->use));
 		return 0;