Re: [PATCH] drivers/s390/char/tty3270: Remove function callback casts

[Oscar Carter]

On Sat, Jun 27, 2020 at 09:10:56AM -0700, Kees Cook wrote:
> On Sat, Jun 27, 2020 at 02:54:17PM +0200, Oscar Carter wrote:
> > In an effort to enable -Wcast-function-type in the top-level Makefile to
> > support Control Flow Integrity builds, remove all the function callback
> > casts.
> >
> > To do this modify the function prototypes accordingly.
> >
> > Signed-off-by: Oscar Carter <oscar.carter@xxxxxxx>
>
> Oh yes, the tasklets! I'd love to see this fixed correctly. (Which is to
> say, modernize the API.) Romain hasn't had time to continue the work:
> https://lore.kernel.org/kernel-hardening/20190929163028.9665-1-romain.perier@xxxxxxxxx/
>
> Is this something you'd want to tackle?

Yes, of course. It will be a pleasure to work on this. But without forgetting
the work to remove all the function cast mismatches.

> > ---
> >  drivers/s390/char/tty3270.c | 12 ++++++------
> >  1 file changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/s390/char/tty3270.c b/drivers/s390/char/tty3270.c
> > index 98d7fc152e32..aec996de44d9 100644
> > --- a/drivers/s390/char/tty3270.c
> > +++ b/drivers/s390/char/tty3270.c
> > @@ -556,8 +556,9 @@ tty3270_scroll_backward(struct kbd_data *kbd)
> >   * Pass input line to tty.
> >   */
> >  static void
> > -tty3270_read_tasklet(struct raw3270_request *rrq)
> > +tty3270_read_tasklet(unsigned long data)
> >  {
> > +	struct raw3270_request *rrq = (struct raw3270_request *)data;
>
> Regardless, this is correct as far as fixing the prototype.
>
> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
>
> --
> Kees Cook

Regards,
Oscar Carter