On Sat, Jan 18, 2025 at 04:36:15PM +0100, Greg KH wrote:
> On Sat, Jan 18, 2025 at 03:50:45PM +0100, Dave Penkler wrote:
> > When the detach function is called after a failed attach
> > the usb_dev initialization can cause a NULL pointer
> > dereference. This happens when the usb device is not found
> > in the attach procedure.
> >
> > Remove the usb_dev variable and initialization and change the dev
> > in the dev_info message from the usb_dev to the gpib_dev.
> >
> > Fixes: fbae7090f30c ("staging: gpib: Update messaging and usb_device refs in agilent_usb")
> > Signed-off-by: Dave Penkler <dpenkler@xxxxxxxxx>
> > ---
> > drivers/staging/gpib/agilent_82357a/agilent_82357a.c | 4 +---
> > 1 file changed, 1 insertion(+), 3 deletions(-)
> >
> > diff --git a/drivers/staging/gpib/agilent_82357a/agilent_82357a.c b/drivers/staging/gpib/agilent_82357a/agilent_82357a.c
> > index 34d85a1bdb37..2aaccebc3c7b 100644
> > --- a/drivers/staging/gpib/agilent_82357a/agilent_82357a.c
> > +++ b/drivers/staging/gpib/agilent_82357a/agilent_82357a.c
> > @@ -1442,12 +1442,10 @@ static int agilent_82357a_go_idle(gpib_board_t *board)
> > static void agilent_82357a_detach(gpib_board_t *board)
> > {
> > struct agilent_82357a_priv *a_priv;
> > - struct usb_device *usb_dev;
> >
> > mutex_lock(&agilent_82357a_hotplug_lock);
> >
> > a_priv = board->private_data;
> > - usb_dev = interface_to_usbdev(a_priv->bus_interface);
> > if (a_priv) {
> > if (a_priv->bus_interface) {
> > agilent_82357a_go_idle(board);
> > @@ -1459,7 +1457,7 @@ static void agilent_82357a_detach(gpib_board_t *board)
> > agilent_82357a_cleanup_urbs(a_priv);
> > agilent_82357a_free_private(a_priv);
> > }
> > - dev_info(&usb_dev->dev, "%s: detached\n", __func__);
> > + dev_info(board->gpib_dev, "%s: detached\n", __func__);
>
> In the future, these dev_info() lines all need to go away as when
> drivers work properly, they should be quiet. I'll take this fix for now
> as it's needed, just something to plan on for the future cleanups here.
>
> thanks,
>
> greg k-h
OK
thanks,
-dave
