Reference:https://src.fedoraproject.org/rpms/openssh/blob/f33/f/openssh-8.4p1-cve-2021-28041.patch
diff --git a/ssh-agent.c b/ssh-agent.c
index 6e536e5..3bac42d 100644
--- a/ssh-agent.c
+++ b/ssh-agent.c
@@ -496,6 +496,7 @@ process_add_identity(SocketEntry *e)
 				goto err;
 			}
 			free(ext_name);
+			ext_name = NULL;
 			break;
 		default:
 			error("%s: Unknown constraint %d", __func__, ctype);
-- 
1.8.3.1