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From:   Robert Foss <robert.foss@linaro.org>
Date:   Fri, 22 Jan 2021 10:24:47 +0100
Message-ID: <CAG3jFythAY8AqANV6PiQOus0Nhf0M8kdD-0Pneg5EN5BeE=wkQ@mail.gmail.com>
Subject: Re: [PATCH 1/2] media: dvb-usb: Fix memory leak at error in dvb_usb_device_init()
To:     Takashi Iwai <tiwai@suse.de>
Cc:     Mauro Carvalho Chehab <mchehab@kernel.org>,
        linux-media <linux-media@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Stefan Seyfried <seife+kernel@b1-systems.com>
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Hey Takashi,

Thanks for the patch. It looks good to me, feel free to add my r-b.
Reviewed-by: Robert Foss <robert.foss@linaro.org>


On Wed, 20 Jan 2021 at 12:51, Takashi Iwai <tiwai@suse.de> wrote:
>
> dvb_usb_device_init() allocates a dvb_usb_device object, but it
> doesn't release it even when returning an error.  The callers don't
> seem caring it as well, hence those memories are leaked.
>
> This patch assures releasing the memory at the error path in
> dvb_usb_device_init().  Also it makes sure that USB intfdata is reset
> and don't return the bogus pointer to the caller at the error path,
> too.
>
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Takashi Iwai <tiwai@suse.de>
> ---
>  drivers/media/usb/dvb-usb/dvb-usb-init.c | 18 ++++++++++++------
>  1 file changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/media/usb/dvb-usb/dvb-usb-init.c b/drivers/media/usb/dvb-usb/dvb-usb-init.c
> index c1a7634e27b4..5befec87f26a 100644
> --- a/drivers/media/usb/dvb-usb/dvb-usb-init.c
> +++ b/drivers/media/usb/dvb-usb/dvb-usb-init.c
> @@ -281,15 +281,21 @@ int dvb_usb_device_init(struct usb_interface *intf,
>
>         usb_set_intfdata(intf, d);
>
> -       if (du != NULL)
> +       ret = dvb_usb_init(d, adapter_nums);
> +       if (ret) {
> +               info("%s error while loading driver (%d)", desc->name, ret);
> +               goto error;
> +       }
> +
> +       if (du)
>                 *du = d;
>
> -       ret = dvb_usb_init(d, adapter_nums);
> +       info("%s successfully initialized and connected.", desc->name);
> +       return 0;
>
> -       if (ret == 0)
> -               info("%s successfully initialized and connected.", desc->name);
> -       else
> -               info("%s error while loading driver (%d)", desc->name, ret);
> + error:
> +       usb_set_intfdata(intf, NULL);
> +       kfree(d);
>         return ret;
>  }
>  EXPORT_SYMBOL(dvb_usb_device_init);
> --
> 2.26.2
>