Re: [PATCH 4/4] tty: n_gsm: fix missing corner cases in gsmld_poll()

[Jiri Slaby]

On 07. 07. 22, 9:00, Starke, Daniel wrote:
> > > @@ -3051,14 +3051,20 @@ static __poll_t gsmld_poll(struct tty_struct *tty, struct file *file,
> > >    	__poll_t mask = 0;
> > >    	struct gsm_mux *gsm = tty->disc_data;
> > >    
> > > +	if (!gsm)
> > > +		return EPOLLHUP;
> >
> > Hmm, how can this happen? It's a tty bug if it calls ld ops after NULLing
> > disc_data.
>
> I can remove this check if it is redundant. Should I?

Sure as it makes little sense anyway. Even if gsm was non-NULL here, the 
backing disc_data would be freed on the accesses further.

thanks,
--
js
suse labs