Re: [PATCH net] net: hso: check for allocation failure in hso_create_bulk_serial_device()

[Johan Hovold <johan@kernel.org>]

On Wed, May 12, 2021 at 01:09:04PM +0300, Dan Carpenter wrote:
> Add a couple checks for if these allocations fail.
> 
> Fixes: 542f54823614 ("tty: Modem functions for the HSO driver")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
>  drivers/net/usb/hso.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c
> index 3ef4b2841402..3b2a868d7a72 100644
> --- a/drivers/net/usb/hso.c
> +++ b/drivers/net/usb/hso.c
> @@ -2618,9 +2618,13 @@ static struct hso_device *hso_create_bulk_serial_device(
>  		num_urbs = 2;
>  		serial->tiocmget = kzalloc(sizeof(struct hso_tiocmget),
>  					   GFP_KERNEL);
> +		if (!serial->tiocmget)
> +			goto exit;

Nice catch; the next assignment would go boom if this ever failed.

This appears to have been introduced by 

	af0de1303c4e ("usb: hso: obey DMA rules in tiocmget")

>  		serial->tiocmget->serial_state_notification
>  			= kzalloc(sizeof(struct hso_serial_state_notification),
>  					   GFP_KERNEL);
> +		if (!serial->tiocmget->serial_state_notification)
> +			goto exit;
>  		/* it isn't going to break our heart if serial->tiocmget
>  		 *  allocation fails don't bother checking this.
>  		 */

You should remove this comment and drop the conditional on the following
line as well now, though.

Johan