Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Jiasheng Jiang <jiasheng@iscas.ac.cn>
To:     jiri@resnulli.us
Cc:     jesse.brandeburg@intel.com, anthony.l.nguyen@intel.com,
        davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
        pabeni@redhat.com, intel-wired-lan@lists.osuosl.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jiasheng Jiang <jiasheng@iscas.ac.cn>
Subject: Re: [PATCH net] ice: Add check for kzalloc
Date:   Wed,  7 Dec 2022 10:20:00 +0800
Message-Id: <20221207022000.44043-1-jiasheng@iscas.ac.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

On Tue, Dec 06, 2022 at 05:47:01PM +0800, Jiri Pirko wrote:
>>As kzalloc may fail and return NULL pointer,
>>it should be better to check the return value
>>in order to avoid the NULL pointer dereference.
> 
> Okay, so? Be imperative to the code base, tell it what to do in your
> patch description.

OK, I will describe the changes by the patch in more details.

>>@@ -462,6 +462,17 @@ static struct tty_driver *ice_gnss_create_tty_driver(struct ice_pf *pf)
>> 					       GFP_KERNEL);
>> 		pf->gnss_serial[i] = NULL;
>> 
>>+		if (!pf->gnss_tty_port[i]) {
>>+			for (j = 0; j < i; j++) {
>>+				tty_port_destroy(pf->gnss_tty_port[j]);
> 
> You are destroying port which you didn't call (pf->gnss_tty_port[i])
> for. Also, you are introducing a code duplication here with the error
> path couple of lines below. Please convert this to goto-label error
> path so the cleanup code is shared.

I will convert this to goto-label in v2.
But I have a question that the j is from 0 to (i - 1), and therefore only
the initialized port will be destroyed.
Is there any wrong?

Thanks,
Jiang