Re: [PATCHv4]Checks for Null value in function *get_skub

[Levente Kurusa <levex@linux.com>]

On 06/16/2014 05:30 PM, Steve Wise wrote:
> On 6/16/2014 10:25 AM, Nicholas Krause wrote:
>> Signed-off-by: Nicholas Krause <xerofoify@gmail.com>
>> ---
>>   drivers/infiniband/hw/cxgb4/cm.c | 8 +++-----
>>   1 file changed, 3 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
>> index f9477e2..2d56983 100644
>> --- a/drivers/infiniband/hw/cxgb4/cm.c
>> +++ b/drivers/infiniband/hw/cxgb4/cm.c
>> @@ -340,15 +340,13 @@ static int status2errno(int status)
>>    */
>>   static struct sk_buff *get_skb(struct sk_buff *skb, int len, gfp_t gfp)
>>   {
>>   if (skb && !skb_is_nonlinear(skb) && !skb_cloned(skb)) {
>>                  skb_trim(skb, 0);
>>                  skb_get(skb);
>>                  skb_reset_transport_header(skb);
>>       } else {
>> +        if (skb)
>> +            kfree_skb (skb);
>>           skb = alloc_skb(len, gfp);
>>       }
>>       t4_set_arp_err_handler(skb, NULL, NULL);
>
> Can you change the comment?  This patch is now fixing a potential skb leak.
> Also, kfree_sb() will ignore NULL ptrs, so we could just always call it.
 > But I'd add a comment like /* NULL is ignored */.

AFAIK, checkpatch.pl will show you a message if it detects this:

if (x)
     kfree(x);

so I guess it is not really needed.

Thanks,
     Levente Kurusa.