[PATCH] USB: serial: bus: fix const issue in usb_serial_device_match()

[PATCH] USB: serial: bus: fix const issue in usb_serial_device_match()

[Greg Kroah-Hartman]

usb_serial_device_match() takes a const pointer, and then decides to
cast it away into a non-const one, which is not a good thing to do
overall.  Fix this up by properly setting the pointers to be const to
preserve that attribute.

Cc: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/serial/bus.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/serial/bus.c b/drivers/usb/serial/bus.c
index 2fea1b1db4a2..9e2a18c0b218 100644
--- a/drivers/usb/serial/bus.c
+++ b/drivers/usb/serial/bus.c
@@ -17,7 +17,7 @@ static int usb_serial_device_match(struct device *dev,
 				   const struct device_driver *drv)
 {
 	const struct usb_serial_port *port = to_usb_serial_port(dev);
-	struct usb_serial_driver *driver = to_usb_serial_driver(drv);
+	const struct usb_serial_driver *driver = to_usb_serial_driver(drv);
 
 	/*
 	 * drivers are already assigned to ports in serial_probe so it's
-- 
2.49.0

Re: [PATCH] USB: serial: bus: fix const issue in usb_serial_device_match()

[Johan Hovold]

On Wed, May 21, 2025 at 03:41:34PM +0200, Greg Kroah-Hartman wrote:
> usb_serial_device_match() takes a const pointer, and then decides to
> cast it away into a non-const one, which is not a good thing to do
> overall.  Fix this up by properly setting the pointers to be const to
> preserve that attribute.

I think this deserves a Fixes tag as this is a recent issue introduced
by commit d69d80484598 ("driver core: have match() callback in struct
bus_type take a const *") (even if we only use the address of the
pointer).

> Cc: Johan Hovold <johan@kernel.org>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

> @@ -17,7 +17,7 @@ static int usb_serial_device_match(struct device *dev,
>  				   const struct device_driver *drv)
>  {
>  	const struct usb_serial_port *port = to_usb_serial_port(dev);
> -	struct usb_serial_driver *driver = to_usb_serial_driver(drv);
> +	const struct usb_serial_driver *driver = to_usb_serial_driver(drv);
>  
>  	/*
>  	 * drivers are already assigned to ports in serial_probe so it's

Now applied with a Fixes tag added.

Johan

Re: [PATCH] USB: serial: bus: fix const issue in usb_serial_device_match()

[Greg Kroah-Hartman]

On Wed, May 21, 2025 at 05:09:23PM +0200, Johan Hovold wrote:
> On Wed, May 21, 2025 at 03:41:34PM +0200, Greg Kroah-Hartman wrote:
> > usb_serial_device_match() takes a const pointer, and then decides to
> > cast it away into a non-const one, which is not a good thing to do
> > overall.  Fix this up by properly setting the pointers to be const to
> > preserve that attribute.
> 
> I think this deserves a Fixes tag as this is a recent issue introduced
> by commit d69d80484598 ("driver core: have match() callback in struct
> bus_type take a const *") (even if we only use the address of the
> pointer).

Oops, yes, that is needed, sorry about that.

> > Cc: Johan Hovold <johan@kernel.org>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> 
> > @@ -17,7 +17,7 @@ static int usb_serial_device_match(struct device *dev,
> >  				   const struct device_driver *drv)
> >  {
> >  	const struct usb_serial_port *port = to_usb_serial_port(dev);
> > -	struct usb_serial_driver *driver = to_usb_serial_driver(drv);
> > +	const struct usb_serial_driver *driver = to_usb_serial_driver(drv);
> >  
> >  	/*
> >  	 * drivers are already assigned to ports in serial_probe so it's
> 
> Now applied with a Fixes tag added.

Great, thanks!

greg k-h