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Date:   Sat, 10 Jun 2023 12:01:06 +0800
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Subject: Re: [PATCH net-next] net: ethtool: Fix out-of-bounds copy to user
From:   Ding Hui <dinghui@sangfor.com.cn>
To:     Alexander Duyck <alexander.duyck@gmail.com>,
        Jakub Kicinski <kuba@kernel.org>
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On 2023/6/10 11:47, Ding Hui wrote:
> On 2023/6/10 1:59, Alexander Duyck wrote:
>> On Fri, Jun 9, 2023 at 10:13 AM Jakub Kicinski <kuba@kernel.org> wrote:
>>>
>>> On Fri, 9 Jun 2023 23:25:34 +0800 Ding Hui wrote:
>>>> drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c: .get_sset_count         = nfp_net_get_sset_count,
>>>> drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c: .get_sset_count         = nfp_port_get_sset_count,
>>>
>>> Not sure if your research is accurate, NFP does not change the number
>>> of stats. The number depends on the device and the FW loaded, but those
>>> are constant during a lifetime of a netdevice.
> 
> Sorry, my research is rough indeed.
> 
>>
>> Yeah, the value doesn't need to be a constant, it just need to be constant.
>>
>> So for example in the ixgbe driver I believe we were using the upper
>> limits on the Tx and Rx queues which last I recall are stored in the
>> netdev itself.
>>
> Thanks to point that, the examples NFP and ixgbe do help me.

The commit f8ba7db85035 ("ice: Report stats for allocated queues via ethtool stats")
also helps a lot.

-- 
Thanks,
-dinghui