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Date: Fri, 24 Jan 2025 17:29:53 -0800
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Subject: Re: [RFC PATCH net-next v6 08/13] net-timestamp: support hw
 SCM_TSTAMP_SND for bpf extension
To: Jason Xing <kerneljasonxing@gmail.com>
Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
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References: <20250121012901.87763-1-kerneljasonxing@gmail.com>
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From: Martin KaFai Lau <martin.lau@linux.dev>
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On 1/24/25 5:18 PM, Jason Xing wrote:
>>> @@ -5577,9 +5578,9 @@ static void skb_tstamp_tx_bpf(struct sk_buff *skb, struct sock *sk,
>>>                op = BPF_SOCK_OPS_TS_SCHED_OPT_CB;
>>>                break;
>>>        case SCM_TSTAMP_SND:
>>> +             op = sw ? BPF_SOCK_OPS_TS_SW_OPT_CB : BPF_SOCK_OPS_TS_HW_OPT_CB;
>>>                if (!sw)
>>> -                     return;
>>> -             op = BPF_SOCK_OPS_TS_SW_OPT_CB;
>>> +                     *skb_hwtstamps(skb) = *hwtstamps;
>> hwtstamps may still be NULL, no?
> Right, it can be zero if something wrong happens.

Then it needs a NULL check, no?