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Subject: Re: [PATCH v2] USB: cdc-acm: fix minor-number release
To:     Johan Hovold <johan@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org, Jaejoong Kim <climbbb.kim@gmail.com>
References: <20210907082318.7757-1-johan@kernel.org>
From:   Oliver Neukum <oneukum@suse.com>
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Date:   Tue, 7 Sep 2021 10:53:18 +0200
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On 07.09.21 10:23, Johan Hovold wrote:
> If the driver runs out of minor numbers it would release minor 0 and
> allow another device to claim the minor while still in use.
>
> Fortunately, registering the tty class device of the second device would
> fail (with a stack dump) due to the sysfs name collision so no memory is
> leaked.
>
> Fixes: cae2bc768d17 ("usb: cdc-acm: Decrement tty port's refcount if probe() fail")
> Cc: stable@vger.kernel.org      # 4.19
> Cc: Jaejoong Kim <climbbb.kim@gmail.com>
> Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Oliver Neukum <oneukum@suse.com>