Re: [PATCH v2] Bluetooth: Add NULL check for tiocmget() and tiocmset()

From: Myungho Jung
Date: Sun Feb 03 2019 - 01:39:14 EST


On Thu, Jan 31, 2019 at 04:40:00PM +0100, Johan Hovold wrote:
> On Tue, Jan 29, 2019 at 09:39:28PM -0800, Myungho Jung wrote:
> > tiocmget() and tiocmset() operations are optional and some tty drivers
> > like pty miss the operations. We need NULL check to prevent from
> > dereference.
> >
> > Signed-off-by: Myungho Jung <mhjungk@xxxxxxxxx>
> > ---
> > drivers/bluetooth/hci_ath.c | 6 ++++++
> > drivers/bluetooth/hci_ldisc.c | 4 ++++
> > 2 files changed, 10 insertions(+)
>
> Ah, you had already submitted a v2.
>
> I still suggest splitting this one in two patches and that you add a
> Fixes and stable tag to each so that they both get backported to stable.
>
> Also, when resubmitting, make sure to include a short changelog here
> below the cut-off line (---).
>
> >
> > diff --git a/drivers/bluetooth/hci_ath.c b/drivers/bluetooth/hci_ath.c
> > index d568fbd94d6c..fb9f6323a911 100644
> > --- a/drivers/bluetooth/hci_ath.c
> > +++ b/drivers/bluetooth/hci_ath.c
> > @@ -185,8 +185,14 @@ static int ath_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
> >
> > static int ath_setup(struct hci_uart *hu)
> > {
> > + struct tty_struct *tty = hu->tty;
> > +
> > BT_DBG("hu %p", hu);
> >
> > + /* tty driver should support operations to set RTS */
> > + if (!tty->driver->ops->tiocmget || !tty->driver->ops->tiocmset)
> > + return -EOPNOTSUPP;
>
> -ENODEV might be more appropriate.
>
> Johan

I'll split into 2 seperate patches. So, do I need to add stable tag on each
patch like below to be cherry-picked?

Cc: <stable@xxxxxxxxxxxxxxx> # <hash>: <summary>

I looked for a good example from mailing list but didn't find one.

Thanks,
Myungho