Re: [PATCH v2] ath10k: Fix the parsing error in service available event

[Kalle Valo]

Doug Anderson <dianders@xxxxxxxxxxxx> writes:

>>  static int ath10k_wmi_tlv_op_pull_svc_avail(struct ath10k *ar,
>> diff --git a/drivers/net/wireless/ath/ath10k/wmi.c b/drivers/net/wireless/ath/ath10k/wmi.c
>> index 1fa7107..2e4b561 100644
>> --- a/drivers/net/wireless/ath/ath10k/wmi.c
>> +++ b/drivers/net/wireless/ath/ath10k/wmi.c
>> @@ -5751,8 +5751,9 @@ void ath10k_wmi_event_service_available(struct ath10k *ar, struct sk_buff *skb)
>>                             ret);
>>         }
>>
>> -       ath10k_wmi_map_svc_ext(ar, arg.service_map_ext, ar->wmi.svc_map,
>> -                              __le32_to_cpu(arg.service_map_ext_len));
>> +       if (arg.service_map_ext_valid)
>> +               ath10k_wmi_map_svc_ext(ar, arg.service_map_ext, ar->wmi.svc_map,
>> +                                      __le32_to_cpu(arg.service_map_ext_len));
>
> Your new patch still requires the caller to init the
> "service_map_ext_valid" to false before calling, but I guess there's
> not a whole lot more we can do because we might be parsing more than
> one tag.  It does seem nice that at least we now have a validity bit
> instead of just relying on a non-zero length to be valid.
>
> It might be nice to have a comment saying that it's up to us to init
> "arg.service_map_ext_valid" to false before calling
> ath10k_wmi_pull_svc_avail(), but I won't insist.  Maybe that's obvious
> to everyone but me...

It's not obvious to me either. Please add that comment.

BTW, for some reason Doug's response didn't get to patchwork:

https://patchwork.kernel.org/project/linux-wireless/patch/1603904469-598-1-git-send-email-pillair@xxxxxxxxxxxxxx/

Though I do see it in linux-wireless, so most likely this was a
temporary glitch in patchwork. But it's just worrisome as nowadays I
only check the comments in patchwork before I apply the patch.

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