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 X-Spam-Level: X-Spam-Status: No, score=-13.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 906FFC04AB6 for ; Tue, 28 May 2019 13:04:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 62D0C208CB for ; Tue, 28 May 2019 13:04:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="J8H0J62x" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727521AbfE1NE1 (ORCPT ); Tue, 28 May 2019 09:04:27 -0400 Received: from mail-qk1-f196.google.com ([209.85.222.196]:35575 "EHLO mail-qk1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726867AbfE1NE1 (ORCPT ); Tue, 28 May 2019 09:04:27 -0400 Received: by mail-qk1-f196.google.com with SMTP id l128so9670005qke.2; Tue, 28 May 2019 06:04:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=egUCFMOxotUyHIdIWxsbEKKLZ6dJOCt5AUpAksGL1lg=; b=J8H0J62x8W8HGq14K2pJGI1+GA51ibXL/47coBaf5N/guzHKGxJEOTEcLlc3YisQM9 JOadIZe3jD4L4eo3HECB/M9w51QNl1T75+F1ULBk6ITNXXsepWRd9h7mP7CuS9aUtyxV abD/7z8EizLvxrceUJfc4gcygvJWW24mLUy/rjCJcoBzarsN3BAwAMk5Xvfs+/BTtD7l cbFOw3MxgZqxPqId80CnBtXxbjP6GMPYq1EIR8bkASIn0Mr2aVaEzsK/Ksq3xGG+wcni jUmT3ImfsyOlPQN+jDBMPncuaDJC0ho6K69GXtEfDJLWMmG0W981GnFRUY2Tg9zy1LrX t+Ag== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=egUCFMOxotUyHIdIWxsbEKKLZ6dJOCt5AUpAksGL1lg=; b=KJU/hDHo6O7AlHBBzWtT4XSt/CTx8i6YDJVzG1pig2sXRIffPtiblClCmybMMiZJUj dW4DIhhsqx2naj570D08eSjR/8KqC98mWZOkoDZ+ezIYO92ZNY1hIp+E82sbF28yAUMN Qkt1VDdHFZRqjT7KRGXYtVDfIjan4EOFtrnC12Y/+bvpPC8h42OgVoZPbSHVYdiazaFF k4/KIm89z87css6TMP6+8S6uLJ9Qj6AxqZQyq9RwvtMX9SihZtn0+otu2CvicxRm8ZGC ZVRDUAOQ73HROMroAhcEKYJ5ASBZRt+hHn2DlYPlz4MORnSBZcZvh/0c2dPBBgxwe8It r2KQ== X-Gm-Message-State: APjAAAV18Yraw+Kp0J8E02FdXa0x6o6/TRLr4lnPyFRhee1uvKI3ituK XDFa04FgQvUd0fgQM1OXIZQ= X-Google-Smtp-Source: APXvYqzbcD2ludIojGHX3Bbl+vGO/Mj/I4IVRYIfy3ktIje4Rx3G5QQNc6a+74tazkHgneOlG6OHnQ== X-Received: by 2002:ac8:27fb:: with SMTP id x56mr64343242qtx.14.1559048666178; Tue, 28 May 2019 06:04:26 -0700 (PDT) Received: from quaco.ghostprotocols.net ([179.97.35.11]) by smtp.gmail.com with ESMTPSA id k5sm1465865qtj.40.2019.05.28.06.04.25 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Tue, 28 May 2019 06:04:25 -0700 (PDT) From: Arnaldo Carvalho de Melo X-Google-Original-From: Arnaldo Carvalho de Melo Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id F1CAE41149; Tue, 28 May 2019 10:04:21 -0300 (-03) Date: Tue, 28 May 2019 10:04:21 -0300 To: Shawn Landden Cc: Ingo Molnar , Thomas Gleixner , Jiri Olsa , Namhyung Kim , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Adrian Hunter , Jiri Olsa , Wang Nan , Arnaldo Carvalho de Melo Subject: Re: [PATCH 05/44] perf data: Fix 'strncat may truncate' build failure with recent gcc Message-ID: <20190528130421.GB13830@kernel.org> References: <20190527223730.11474-1-acme@kernel.org> <20190527223730.11474-6-acme@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.11.3 (2019-02-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Mon, May 27, 2019 at 05:46:26PM -0500, Shawn Landden escreveu: > On Mon, May 27, 2019 at 5:38 PM Arnaldo Carvalho de Melo > wrote: > > > > From: Shawn Landden > > > > This strncat() is safe because the buffer was allocated with zalloc(), > > however gcc doesn't know that. Since the string always has 4 non-null > > bytes, just use memcpy() here. > > > > CC /home/shawn/linux/tools/perf/util/data-convert-bt.o > > In file included from /usr/include/string.h:494, > > from /home/shawn/linux/tools/lib/traceevent/event-parse.h:27, > > from util/data-convert-bt.c:22: > > In function ‘strncat’, > > inlined from ‘string_set_value’ at util/data-convert-bt.c:274:4: > > /usr/include/powerpc64le-linux-gnu/bits/string_fortified.h:136:10: error: ‘__builtin_strncat’ output may be truncated copying 4 bytes from a string of length 4 [-Werror=stringop-truncation] > > 136 | return __builtin___strncat_chk (__dest, __src, __len, __bos (__dest)); > > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > Signed-off-by: Shawn Landden > > Cc: Adrian Hunter > > Cc: Jiri Olsa > > Cc: Namhyung Kim > > Cc: Wang Nan > > LPU-Reference: 20190518183238.10954-1-shawn@git.icu > > Link: https://lkml.kernel.org/n/tip-289f1jice17ta7tr3tstm9jm@git.kernel.org > > Signed-off-by: Arnaldo Carvalho de Melo > > --- > > tools/perf/util/data-convert-bt.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/tools/perf/util/data-convert-bt.c b/tools/perf/util/data-convert-bt.c > > index e0311c9750ad..9097543a818b 100644 > > --- a/tools/perf/util/data-convert-bt.c > > +++ b/tools/perf/util/data-convert-bt.c > > @@ -271,7 +271,7 @@ static int string_set_value(struct bt_ctf_field *field, const char *string) > > if (i > 0) > > strncpy(buffer, string, i); > > } > > - strncat(buffer + p, numstr, 4); > > + memcpy(buffer + p, numstr, 4); > I took care to have enough context in my patch that you could see what > was going on. I wonder if there is a way to make that care > propate when people add Signed-off-by: lines. I just checked and the patch is the same, the description I only changed the subject line, so that when one uses: git log --oneline we can know what is the component and what kind of build failure was that. - Arnaldo > > p += 3; > > } > > } > > -- > > 2.20.1 > > -- - Arnaldo