Re: [PATCH net-next] rocker: fix a neigh entry leak issue

[David Miller <davem@davemloft.net>]

From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 14 May 2015 07:06:22 -0700

> On Thu, 2015-05-14 at 15:06 +0800, Ying Xue wrote:
>> Once we get a neighbour through looking up arp cache or creating a
>> new one in rocker_port_ipv4_resolve(), the neighbour's refcount is
>> already taken. But we don't put the refcount again after it's used,
>> which make the neighbour entry leaked.
>> 
>> Signed-off-by: Ying Xue <ying.xue@windriver.com>
>> ---
>>  drivers/net/ethernet/rocker/rocker.c |    1 +
>>  1 file changed, 1 insertion(+)
>> 
>> diff --git a/drivers/net/ethernet/rocker/rocker.c b/drivers/net/ethernet/rocker/rocker.c
>> index 1fc006b..7504540 100644
>> --- a/drivers/net/ethernet/rocker/rocker.c
>> +++ b/drivers/net/ethernet/rocker/rocker.c
>> @@ -3053,6 +3053,7 @@ static int rocker_port_ipv4_resolve(struct rocker_port *rocker_port,
>>  	else
>>  		neigh_event_send(n, NULL);
>>  
>> +	neigh_release(n);
>>  	return err;
>>  }
>>  
> 
> I do not think this fix is complete.
> 
> neigh_create() can return an error, and we'll crash.

Correct, neigh_create() return values must be checked with IS_ERR().