From 82d3b3d11b34147c55a3d32aa0b77a3de883f712 Mon Sep 17 00:00:00 2001
From: "Yukihiro \"Matz\" Matsumoto" <matz@ruby.or.jp>
Date: Fri, 1 Apr 2022 16:40:06 +0900
Subject: [PATCH] vm.c: target class may be NULL.

Address CVE-2022-1201
---
 src/vm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/vm.c b/src/vm.c
index e4a6cd67c..8a79b950c 100644
--- a/src/vm.c
+++ b/src/vm.c
@@ -1758,7 +1758,7 @@ RETRY_TRY_BLOCK:
       }
       else if (target_class->tt == MRB_TT_MODULE) {
         target_class = mrb_vm_ci_target_class(ci);
-        if (target_class->tt != MRB_TT_ICLASS) {
+        if (!target_class || target_class->tt != MRB_TT_ICLASS) {
           goto super_typeerror;
         }
       }