diff --git a/src/api.c b/src/api.c
index 6b808cf7df17cbe19d87767a7ec6ba53a4c4a30e_c3JjL2FwaS5j..8a3b91a7e20462303960e749d771ca1a7cade7ad_c3JjL2FwaS5j 100644
--- a/src/api.c
+++ b/src/api.c
@@ -117,7 +117,12 @@
 YAML_DECLARE(int)
 yaml_stack_extend(void **start, void **top, void **end)
 {
-    void *new_start = yaml_realloc(*start, ((char *)*end - (char *)*start)*2);
+    void *new_start;
+
+    if ((char *)*end - (char *)*start >= INT_MAX / 2)
+	return 0;
+
+    new_start = yaml_realloc(*start, ((char *)*end - (char *)*start)*2);
 
     if (!new_start) return 0;