Re: [PATCH net-next 11/15] mptcp: pm: add id parameter for get_addr

[Matthieu Baerts <matttbe@kernel.org>]

Hi Simon,

On 17/01/2025 11:43, Simon Horman wrote:
> On Thu, Jan 16, 2025 at 05:51:33PM +0100, Matthieu Baerts (NGI0) wrote:
>> From: Geliang Tang <tanggeliang@kylinos.cn>
>>
>> The address id is parsed both in mptcp_pm_nl_get_addr() and
>> mptcp_userspace_pm_get_addr(), this makes the code somewhat repetitive.
>>
>> So this patch adds a new parameter 'id' for all get_addr() interfaces.
>> The address id is only parsed in mptcp_pm_nl_get_addr_doit(), then pass
>> it to both mptcp_pm_nl_get_addr() and mptcp_userspace_pm_get_addr().
>>
>> Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
>> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
>> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
> 
> ...
> 
>> diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
>> index 853b1ea8680ae753fcb882d8b8f4486519798503..392f91dd21b4ce07efb5f44c701f2261afcdc37e 100644
>> --- a/net/mptcp/pm_netlink.c
>> +++ b/net/mptcp/pm_netlink.c
>> @@ -1773,23 +1773,15 @@ int mptcp_nl_fill_addr(struct sk_buff *skb,
>>  	return -EMSGSIZE;
>>  }
>>  
>> -int mptcp_pm_nl_get_addr(struct genl_info *info)
>> +int mptcp_pm_nl_get_addr(u8 id, struct genl_info *info)
>>  {
>>  	struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
>> -	struct mptcp_pm_addr_entry addr, *entry;
>> +	struct mptcp_pm_addr_entry *entry;
>>  	struct sk_buff *msg;
>>  	struct nlattr *attr;
>>  	void *reply;
>>  	int ret;
>>  
>> -	if (GENL_REQ_ATTR_CHECK(info, MPTCP_PM_ENDPOINT_ADDR))
>> -		return -EINVAL;
>> -
>> -	attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR];
>> -	ret = mptcp_pm_parse_entry(attr, info, false, &addr);
>> -	if (ret < 0)
>> -		return ret;
>> -
> 
> Hi Matthieu and Geliang,
> 
> This hunk removes the initialisation of attr...
> 
>>  	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
>>  	if (!msg)
>>  		return -ENOMEM;
>> @@ -1803,7 +1795,7 @@ int mptcp_pm_nl_get_addr(struct genl_info *info)
>>  	}
>>  
>>  	rcu_read_lock();
>> -	entry = __lookup_addr_by_id(pernet, addr.addr.id);
>> +	entry = __lookup_addr_by_id(pernet, id);
>>  	if (!entry) {
>>  		NL_SET_ERR_MSG_ATTR(info->extack, attr, "address not found");
> 
> ... but attr is still used here.
> 
> Flagged by clang-19 W=1 builds and Smatch.

Thank you for having looked at that!

Indeed, I missed that when rebasing and fixing conflicts, my bad, sorry.

This part of the code is moved in the patch to pm.c, where 'attr' is
initialised properly. What's a shame is that, just before sending the
series, I thought about squashing this patch with the next one :)

Anyway, I will fix that in a v2.

I hope that's OK if I add an extra patch in the same series or in parallel.

Cheers,
Matt
-- 
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