Re: [PATCH v2] scsi: fcoe: add missed kfree() in an error path

From: Jing Xiangfeng <jingxiangfeng@huawei.com>
To: "Ewan D. Milne" <emilne@redhat.com>, <hare@suse.de>,
	<jejb@linux.ibm.com>, <martin.petersen@oracle.com>,
	<robert.w.love@intel.com>, <Neerav.Parikh@intel.com>,
	<Markus.Elfring@web.de>
Cc: <linux-scsi@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] scsi: fcoe: add missed kfree() in an error path
Date: Thu, 16 Jul 2020 16:13:45 +0800	[thread overview]
Message-ID: <5F100C39.5070503@huawei.com> (raw)
In-Reply-To: <d1fa9e60b559b6bf3a37ef5a6aef2bd7bd6e1681.camel@redhat.com>

On 2020/7/14 1:53, Ewan D. Milne wrote:
> See below.
>
> On Thu, 2020-07-09 at 20:05 +0800, Jing Xiangfeng wrote:
>> fcoe_fdmi_info() misses to call kfree() in an error path.
>> Add a label 'free_fdmi' and jump to it.
>>
>> Fixes: f07d46bbc9ba ("fcoe: Fix smatch warning in fcoe_fdmi_info
>> function")
>> Signed-off-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
>> ---
>>   drivers/scsi/fcoe/fcoe.c | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
>> index 25dae9f0b205..a63057a03772 100644
>> --- a/drivers/scsi/fcoe/fcoe.c
>> +++ b/drivers/scsi/fcoe/fcoe.c
>> @@ -830,7 +830,7 @@ static void fcoe_fdmi_info(struct fc_lport
>> *lport, struct net_device *netdev)
>>   		if (rc) {
>>   			printk(KERN_INFO "fcoe: Failed to retrieve FDMI
>> "
>>   					"information from netdev.\n");
>> -			return;
>> +			goto free_fdmi;
>>   		}
>>
>>   		snprintf(fc_host_serial_number(lport->host),
>> @@ -868,6 +868,7 @@ static void fcoe_fdmi_info(struct fc_lport
>> *lport, struct net_device *netdev)
>>
>>   		/* Enable FDMI lport states */
>>   		lport->fdmi_enabled = 1;
>> +free_fdmi:
>>   		kfree(fdmi);
>>   	} else {
>>   		lport->fdmi_enabled = 0;
>
> Normally I would like to see goto labels for error paths outside
> conditionals and at the end of the function.

I agree.

  In this case it would
> seem to be cleaner to put an else { } clause in the if (rc) above
> around the snprintf() calls.

It is ok with me. v1 is also a simpler way.

+Hannes, Which is preferable?

Thanks

>
> -Ewan
>
> .
>