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From:   "Hans Verkuil (hansverk)" <hansverk@cisco.com>
To:     Wen Yang <yellowriver2010@hotmail.com>,
        Hans Verkuil <hans.verkuil@cisco.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>
CC:     Linux Media Mailing List <linux-media@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/4] media: cec-notifier: fix possible object reference
 leak
Thread-Topic: [PATCH 1/4] media: cec-notifier: fix possible object reference
 leak
Thread-Index: AQHUwCH951ryS7AxYU2IkMLJINPqbQ==
Date:   Mon, 11 Feb 2019 10:38:53 +0000
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On 09/02/2019 03:48, Wen Yang wrote:=0A=
> put_device() should be called in cec_notifier_release(),=0A=
> since the dev is being passed down to cec_notifier_get_conn(),=0A=
> which holds reference. On cec_notifier destruction, it=0A=
> should drop the reference to the device.=0A=
> =0A=
> Fixes: 6917a7b77413 ("[media] media: add CEC notifier support")=0A=
> Signed-off-by: Wen Yang <yellowriver2010@hotmail.com>=0A=
> ---=0A=
>  drivers/media/cec/cec-notifier.c | 1 +=0A=
>  1 file changed, 1 insertion(+)=0A=
> =0A=
> diff --git a/drivers/media/cec/cec-notifier.c b/drivers/media/cec/cec-not=
ifier.c=0A=
> index dd2078b..621d4ae 100644=0A=
> --- a/drivers/media/cec/cec-notifier.c=0A=
> +++ b/drivers/media/cec/cec-notifier.c=0A=
> @@ -66,6 +66,7 @@ static void cec_notifier_release(struct kref *kref)=0A=
>  		container_of(kref, struct cec_notifier, kref);=0A=
>  =0A=
>  	list_del(&n->head);=0A=
> +	put_device(n->dev);=0A=
>  	kfree(n->conn);=0A=
>  	kfree(n);=0A=
>  }=0A=
> =0A=
=0A=
Sorry, no. The dev pointer is just a search key that the notifier code look=
s=0A=
for. It is not the notifier's responsibility to take a reference, that woul=
d=0A=
be the responsibility of the hdmi and cec drivers.=0A=
=0A=
If you can demonstrate that there is an object reference leak, then please=
=0A=
provide the details: it is likely a bug elsewhere and not in the notifier=
=0A=
code.=0A=
=0A=
BTW, your patch series didn't arrive on the linux-media mailinglist for=0A=
some reason.=0A=
=0A=
Regards,=0A=
=0A=
	Hans=0A=