LoongArch: Check the return value when creating kobj

commit 51adb03 upstream.

Add a check for the return value of kobject_create_and_add(), to ensure
that the kobj allocation succeeds for later use.

Cc: stable@vger.kernel.org
Signed-off-by: Tao Cui <cuitao@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Tao Cui

arch/loongarch/kernel/env.c

@@ -70,6 +70,8 @@ static int __init boardinfo_init(void)
 	struct kobject *loongson_kobj;
 
 	loongson_kobj = kobject_create_and_add("loongson", firmware_kobj);
+	if (!loongson_kobj)
+		return -ENOMEM;
 
 	return sysfs_create_file(loongson_kobj, &boardinfo_attr.attr);
 }