Re: [PATCH v6 1/3] tracing: eprobe: remove duplicate is_good_name() operation

[Linyu Yuan <quic_linyyuan@quicinc.com>]

hi Tom,

On 6/26/2022 1:25 AM, Tom Zanussi wrote:
> Hi Linyu,
>
> On Tue, 2022-06-21 at 09:59 +0800, Linyu Yuan wrote:
>> traceprobe_parse_event_name() already validate SYSTEM and EVENT name,
>> there is no need to call is_good_name() after it.
>>
>> Add trace_probe_log_set_index(1) to allow report correct error
>> if user input wrong SYSTEM.EVENT format.
>>
>> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
>> Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
>> ---
>> v2: drop v1 change as it is NACK.
>>      add it to remove duplicate is_good_name().
>> v3: move it as first patch.
>> v4: no change
>> v5: add Acked-by tag
>> v6: keep is_good_name() check for group and event name
>>      add trace_probe_log_set_index(1) to report correct error message.
>>
>>   kernel/trace/trace_eprobe.c | 3 +--
>>   1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/kernel/trace/trace_eprobe.c
>> b/kernel/trace/trace_eprobe.c
>> index 7d44785..8979cb9e 100644
>> --- a/kernel/trace/trace_eprobe.c
>> +++ b/kernel/trace/trace_eprobe.c
>> @@ -881,13 +881,12 @@ static int __trace_eprobe_create(int argc,
>> const char *argv[])
>>          if (!is_good_name(event) || !is_good_name(group))
>>                  goto parse_error;
>>   
>> +       trace_probe_log_set_index(1);
> Is this something that you noticed missing in the original code and are
> adding now?  If so, please make this a separate patch.  Or is this
> something that's needed for the new 'generating event name' code?  If
> that's the case, please move this to the other patch.
>
> This one should only contain the code related to the duplicate
> is_good_name() removal mentioned in the subject.  Or if this really
> does belong here, please provide more explanation of why it's needed if
> you remove the duplicate is_good_name() code.
thanks, the original code should have this setting, i will create a 
separate patch.
>
> Thanks,
>
> Tom
>
>>          sys_event = argv[1];
>>          ret = traceprobe_parse_event_name(&sys_event, &sys_name,
>> buf2,
>>                                            sys_event - argv[1]);
>>          if (ret || !sys_name)
>>                  goto parse_error;
>> -       if (!is_good_name(sys_event) || !is_good_name(sys_name))
>> -               goto parse_error;
>>   
>>          mutex_lock(&event_mutex);
>>          event_call = find_and_get_event(sys_name, sys_event);