Re: [PATCH] tty: vcc: Add check for kstrdup() in vcc_probe()

["yiyang (D)" <yiyang13@huawei.com>]

On 2023/9/4 14:17, Greg KH wrote:
> On Mon, Sep 04, 2023 at 11:45:11AM +0800, yiyang (D) wrote:
>> On 2023/9/3 18:49, Greg KH wrote:
>>> 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.
>> Ok, i will send v2 patch for this issue.
>>>
>>> And how did you test this patch?
>>>
>> I use crosstool-ng build sparc arch for open CONFIG_VCC.
> 
> That is build-testing, how did you functionally test that this works
> properly?
> 
Sorry, I only passed the build test, and did not perform the works test 
because there was no corresponding hardware.

thanks,

Yi Yang