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Message-ID: <7272ff00-fa24-8f05-2a5e-bd6fcb8acc45@gmail.com>
Date:   Wed, 21 Sep 2022 17:08:44 +0800
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Subject: Re: [PATCH] net: sched: fix possible refcount leak in
 tc_new_tfilter()
Content-Language: en-US
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     jhs@mojatatu.com, xiyou.wangcong@gmail.com, jiri@resnulli.us,
        davem@davemloft.net, edumazet@google.com, pabeni@redhat.com,
        vladbu@mellanox.com, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20220915085804.20894-1-hbh25y@gmail.com>
 <20220920085006.32c743be@kernel.org>
From:   Hangyu Hua <hbh25y@gmail.com>
In-Reply-To: <20220920085006.32c743be@kernel.org>
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On 20/9/2022 23:50, Jakub Kicinski wrote:
> On Thu, 15 Sep 2022 16:58:04 +0800 Hangyu Hua wrote:
>> tfilter_put need to be called to put the refount got by tp->ops->get to
> 
> s/refount/refcount/
> 
>> avoid possible refcount leak when chain->tmplt_ops == NULL or
>> chain->tmplt_ops != tp->ops.
> 
> This should say:
> 
>    when cain->tmplt_ops != NULL and ...
> 
> otherwise the commit message does not match the code.
> 

My bad. I will submit a v2.

Thanks,
Hangyu

>> Fixes: 7d5509fa0d3d ("net: sched: extend proto ops with 'put' callback")
>> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
>> ---
>>   net/sched/cls_api.c | 1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
>> index 790d6809be81..51d175f3fbcb 100644
>> --- a/net/sched/cls_api.c
>> +++ b/net/sched/cls_api.c
>> @@ -2137,6 +2137,7 @@ static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
>>   	}
>>   
>>   	if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) {
>> +		tfilter_put(tp, fh);
>>   		NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind");
>>   		err = -EINVAL;
>>   		goto errout;
>