Re: How to lock current->signal->tty

Alan Cox
2006-08-08T17:23:57Z

Ar Maw, 2006-08-08 am 13:11 -0400, ysgrifennodd Stephen Smalley:
> Does this look sane? Or do we need a common helper factored from
> disassociate_ctty()? Why is the locking different for TIOCNOTTY in the
> non-leader case?

The non-leader case for TIOCNOTTY in the base kernel is different
because it is wrong and I've fixed that one.

If you can factor disassociate_ctty out to do what you need I'd prefer
that path so the tty locking actually ends up in the tty layer.

> + mutex_lock(&tty_mutex);
> + tty = current->signal->tty;
> if (tty) {
> file_list_lock();

Looks sane and the lock ordering matches vhangup() which may actually
also do what you want - I'm not 100% sure I follow what SELinux tries to
do here.