Re: [PATCH v2] isdn/gigaset: Convert timers to use timer_setup()

From: Paul Bolle
Date: Fri Oct 06 2017 - 15:00:46 EST

On Thu, 2017-10-05 at 12:31 -0700, Kees Cook wrote:
> --- a/drivers/isdn/gigaset/bas-gigaset.c
> +++ b/drivers/isdn/gigaset/bas-gigaset.c

> -static void cmd_in_timeout(unsigned long data)
> +static void cmd_in_timeout(struct timer_list *t)
> {
> - struct cardstate *cs = (struct cardstate *) data;
> - struct bas_cardstate *ucs = cs->hw.bas;
> + struct bas_cardstate *ucs = from_timer(ucs, t, timer_cmd_in);
> + struct urb *urb = ucs->urb_int_in;
> + struct cardstate *cs = urb->context;

This makes me nervous. Are you sure urb->context points to a struct cardstate
here and in the other two places this patch changes?

Anyhow, I'd like to have some time to do my review. So what's your timeframe
here? I do hope I have at least a few weeks. (In other words: I hope gigaset
isn't the only driver where the ability to use random pointers in these timer
callbacks is removed.)


Paul Bolle