Re: [PATCH mptcp-net v7 4/5] mptcp: avoid processing packet if a subflow reset

[Jianguo Wu <wujianguo106@163.com>]

Hi Paolo,

On 2021/6/25 18:45, Paolo Abeni wrote:
> Hi,
> 
> I'm sorry for the partial feedback in my previous reply.
> 
> On Fri, 2021-06-25 at 16:25 +0800, wujianguo106@163.com wrote:
>> @@ -856,7 +856,8 @@ bool mptcp_synack_options(const struct request_sock *req, unsigned int *size,
>>  static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk,
>>  				    struct mptcp_subflow_context *subflow,
>>  				    struct sk_buff *skb,
>> -				    struct mptcp_options_received *mp_opt)
>> +				    struct mptcp_options_received *mp_opt,
>> +				    bool *subflow_is_rst)
> 
> This additional argument is not needed...
> 
> [...]
>> @@ -1053,12 +1057,12 @@ void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb)
>>  			__mptcp_check_push(subflow->conn, sk);
>>  		__mptcp_data_acked(subflow->conn);
>>  		mptcp_data_unlock(subflow->conn);
>> -		return;
>> +		return 1;
>>  	}
>>  
>>  	mptcp_get_options(sk, skb, &mp_opt);
>> -	if (!check_fully_established(msk, sk, subflow, skb, &mp_opt))
>> -		return;
>> +	if (!check_fully_established(msk, sk, subflow, skb, &mp_opt, &subflow_is_rst))
>> +		return subflow_is_rst ? 0 : 1;
> 
> 
> ... here you can simply:
> 
> 		return sk->sk_state != TCP_CLOSE;
> 
> plus some comment above alike:
> 
> """the subflow can be in close state only if check_fully_established()
> just sent a reset. If so, tell the caller to ignore the current
> packet"""
> 

Thank you for all your reviews and suggestions！New version coming soon.

> /P
>