The real problem is that developer (who is a graduate student) doesn't understand how to do use the kernel structure. You can't just have "your own linked lis

The real problem is that developer (who is a graduate student) doesn't understand how to do use the kernel structure. You can't just have "your own linked list". In order to do what you are doing, you have to add a list_head structure to the struct sock structure just for that linked list, and that struct list_head has to be initialized when the struct sock is initialized, and list_del() is called when the struct sock is released --- oh, and you need to handle locking properly to avoid races between adding a struct sock to the list and removing it. Or you can use RCU, but you do need to avoid races one way or another. It's not hard, but you do need to understand the idiom. Why isn't there safety mechanisms? Because the kernel is optimized for speed, and instead of adding run-time checks which can be expensive, there are various debugging tools, including slab poisoning and KASAN to find such issues.