diff --git a/src/validation.c b/src/validation.c
index c2c33d4..bc68558 100644
--- a/src/validation.c
+++ b/src/validation.c
@@ -275,7 +275,7 @@
             struct lyd_ctx_ext_val *ext_v = ext_val->objs[i];
 
             /* validate extension data */
-            ret = ext_v->ext->def->plugin->validate(ext_v->ext, ext_v->sibling, val_opts);
+            ret = ext_v->ext->def->plugin->validate(ext_v->ext, ext_v->sibling, val_opts, diff);
             LY_CHECK_RET(ret);
 
             /* remove this item from the set */