BUG in tty_open when using containers and ptrace

[H. Peter Anvin]

Grzegorz Nosek wrote:
> 
> I tried that and while it did not oops, I wasn't sure where to dput it
> back, so it leaked like a sieve. I'm probably missing something obvious
> but I couldn't find a function whose calls balanced calls to
> devpts_get_tty.
> 
> BTW, what would the semantics be? I.e. what can we do with a pty that has
> its master side long gone?
> 

Nothing, but as long as something is keeping the pts file entry open, it
 should not be garbage-collected.

	-hpa