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Date:   Sun, 3 Sep 2023 12:49:20 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Yi Yang <yiyang13@huawei.com>
Cc:     davem@davemloft.net, jirislaby@kernel.org, jag.raman@oracle.com,
        linux-serial@vger.kernel.org
Subject: Re: [PATCH] tty: vcc: Add check for kstrdup() in vcc_probe()
Message-ID: <2023090321-conch-stopper-51c7@gregkh>
References: <20230903101322.205537-1-yiyang13@huawei.com>
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On Sun, Sep 03, 2023 at 06:13:22PM +0800, Yi Yang wrote:
> Add check for the return value of kstrdup() and return the error, if it
> fails in order to avoid NULL pointer dereference.
> 
> Fixes: 5d171050e28f ("sparc64: vcc: Enable VCC port probe and removal")
> Signed-off-by: Yi Yang <yiyang13@huawei.com>
> ---
>  drivers/tty/vcc.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/tty/vcc.c b/drivers/tty/vcc.c
> index a39ed981bfd3..420d334f6077 100644
> --- a/drivers/tty/vcc.c
> +++ b/drivers/tty/vcc.c
> @@ -579,6 +579,10 @@ static int vcc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
>  		return -ENOMEM;
>  
>  	name = kstrdup(dev_name(&vdev->dev), GFP_KERNEL);
> +	if (!name) {
> +		kfree(port);
> +		return -ENOMEM;

Please just add another goto target later in the function like the rest
of the error paths follow.

And how did you test this patch?

thanks,

greg k-h