From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2D935C433EF for ; Tue, 21 Jun 2022 00:58:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239840AbiFUA6J (ORCPT ); Mon, 20 Jun 2022 20:58:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33148 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242106AbiFUA5k (ORCPT ); Mon, 20 Jun 2022 20:57:40 -0400 Received: from alexa-out.qualcomm.com (alexa-out.qualcomm.com [129.46.98.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 16EDC186F0 for ; Mon, 20 Jun 2022 17:57:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1655773060; x=1687309060; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=25vqwF/B0JGw7RtSnJn5GZoy7OaZTGmwTWDmcGboL0c=; b=uNiKZwOMqFmHBC/d2KKg4R0bhTf1uBMjyn1Et1iuZIziW0dhlXm+v/bV yIIq+8NlqBlVtcy5g0hMKaiUUIvHA3hMKyNQZHjhlzHXqjzMk9tY1xD3Y 9Afs/+MN5RIxnAhZ87R7euGBWMLkmpYkNHGB/dXHm2h6IODiZU1z1zdFh U=; Received: from ironmsg-lv-alpha.qualcomm.com ([10.47.202.13]) by alexa-out.qualcomm.com with ESMTP; 20 Jun 2022 17:57:40 -0700 X-QCInternal: smtphost Received: from nasanex01c.na.qualcomm.com ([10.47.97.222]) by ironmsg-lv-alpha.qualcomm.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jun 2022 17:57:39 -0700 Received: from nalasex01b.na.qualcomm.com (10.47.209.197) by nasanex01c.na.qualcomm.com (10.47.97.222) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.22; Mon, 20 Jun 2022 17:56:59 -0700 Received: from [10.253.10.101] (10.80.80.8) by nalasex01b.na.qualcomm.com (10.47.209.197) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.22; Mon, 20 Jun 2022 17:56:57 -0700 Message-ID: <2f1555ac-709f-8b8b-4a54-cbb653189f30@quicinc.com> Date: Tue, 21 Jun 2022 08:56:55 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [PATCH v4 1/3] tracing: eprobe: remove duplicate is_good_name() operation Content-Language: en-US To: Tom Zanussi , Steven Rostedt , Masami Hiramatsu , Ingo Molnar CC: References: <1654171861-24014-1-git-send-email-quic_linyyuan@quicinc.com> <1654171861-24014-2-git-send-email-quic_linyyuan@quicinc.com> <9a7e0b6087540c9f868d60cbfc88ccefa8070a1b.camel@kernel.org> From: Linyu Yuan In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nalasex01b.na.qualcomm.com (10.47.209.197) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org hi Tom, On 6/21/2022 2:38 AM, Tom Zanussi wrote: > Hi Linyu, > > On Tue, 2022-06-14 at 08:48 +0800, Linyu Yuan wrote: >> hi Tom, >> >> On 6/14/2022 5:01 AM, Tom Zanussi wrote: >>> Hi Linhu, >>> >>> On Thu, 2022-06-02 at 20:10 +0800, Linyu Yuan wrote: >>>> traceprobe_parse_event_name() already validate group and event >>>> name, >>>> there is no need to call is_good_name() after it. >>>> >>>> Signed-off-by: Linyu Yuan >>>> --- >>>> 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 >>>> >>>>   kernel/trace/trace_eprobe.c | 4 ---- >>>>   1 file changed, 4 deletions(-) >>>> >>>> diff --git a/kernel/trace/trace_eprobe.c >>>> b/kernel/trace/trace_eprobe.c >>>> index 7d44785..17d64e3 100644 >>>> --- a/kernel/trace/trace_eprobe.c >>>> +++ b/kernel/trace/trace_eprobe.c >>>> @@ -878,16 +878,12 @@ static int __trace_eprobe_create(int argc, >>>> const char *argv[]) >>>>                  sanitize_event_name(buf1); >>>>                  event = buf1; >>>>          } >>>> -       if (!is_good_name(event) || !is_good_name(group)) >>>> -               goto parse_error; >>> traceprobe_parse_event_name() is only called if (event).  In the >>> !event case, wouldn't the is_good_name() checks still be needed >>> (since >>> in that case buf1 is assigned to event)? >> when user input no  event name, it will generate event name from >> second >> SYSTEM.EVENT, >> >> and it will validate with following traceprobe_parse_event_name(). >> >> > Right, but that happens in your second patch '[PATCH v5 2/3] tracing: > auto generate event name when create a group of events', not this one. > > So if you apply only this patch, the !event case will assign event but > it will remain unchecked when used later in this function. > > It would make more sense to remove this check in patch 2/3 along with > the code that does the generating... thanks, will do like this. > >> ( >> >> if you agree, i will send a new version to update a minor issue in >> second patch, >> >> >>          sys_event = argv[1]; >> -       ret = traceprobe_parse_event_name(&sys_event, &sys_name, >> buf2, >> -                                         sys_event - argv[1]); >> -       if (ret || !sys_name) >> +       ret = traceprobe_parse_event_name(&sys_event, &sys_name, >> buf2, 0); >> +       if (!sys_event || !sys_name) >>                  goto parse_error; >> >> ) >> >>>> >>>>          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; >>> I agree this one isn't needed. > But keep this one in this patch, since it's useful on its own as a > standalone cleanup regardless of whether or not patch 2/3 gets merged. > > Tom > >>> Thanks, >>> >>> Tom >>> >>>> >>>>          mutex_lock(&event_mutex); >>>>          event_call = find_and_get_event(sys_name, sys_event);