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Date:   Tue, 27 Jul 2021 15:37:56 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     Salah Triki <salah.triki@gmail.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Fabio Aiuto <fabioaiuto83@gmail.com>,
        Ross Schmidt <ross.schm.dev@gmail.com>,
        Marco Cesati <marcocesati@gmail.com>,
        Brother Matthew De Angelis <matthew.v.deangelis@gmail.com>,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        Ivan Safonov <insafonov@gmail.com>,
        linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] tablet: acecad: update the reference count of the usb
 interface structure
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On Sat, Jul 24, 2021 at 09:55:42PM +0100, Salah Triki wrote:
> Use usb_get_intf() and usb_put_intf() in order to update the reference
> count of the usb interface structure.
> 

This commit message doesn't say what the user visible effects are.  If
you encountered this bug at runtime then please put the stack trace in
the commit mesage.

Add a Fixes tag.

> Signed-off-by: Salah Triki <salah.triki@gmail.com>
> ---
>  drivers/input/tablet/acecad.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/input/tablet/acecad.c b/drivers/input/tablet/acecad.c
> index a38d1fe97334..85fe134a30ee 100644
> --- a/drivers/input/tablet/acecad.c
> +++ b/drivers/input/tablet/acecad.c
> @@ -151,7 +151,7 @@ static int usb_acecad_probe(struct usb_interface *intf, const struct usb_device_
>  		goto fail2;
>  	}
>  
> -	acecad->intf = intf;
> +	acecad->intf = usb_get_intf(intf);
>  	acecad->input = input_dev;
>  
>  	if (dev->manufacturer)

You need to call usb_put_intf() if input_register_device() fails.

regards,
dan carpenter