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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,USER_AGENT_GIT 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 CAD8FC4321A for ; Tue, 11 Jun 2019 19:01:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A6C6B21841 for ; Tue, 11 Jun 2019 19:01:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560279696; bh=/8nzzgTpLpo7FUdm6nCfC8NOHzv5gXsTv6CLp9XYgAc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=RIBEQhj0rJgxZ8o7TiJ0xfjB4GSxM8CHxP8og+E5ByQEG1PS23EpX5B6XxcUmlDIF 5V7JnRn6urMxS1z2vkQk+QeXkEqpySPtn1KSipm/PYUBiPxVvvVJIsKKVRxX4+MzPL xbBL4z567l+Rj/rsW7gTeRNj9utYr6Pu+nvUSmHc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391926AbfFKTBg (ORCPT ); Tue, 11 Jun 2019 15:01:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:37896 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390751AbfFKTBf (ORCPT ); Tue, 11 Jun 2019 15:01:35 -0400 Received: from quaco.ghostprotocols.net (unknown [179.97.35.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D4368217D6; Tue, 11 Jun 2019 19:01:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560279694; bh=/8nzzgTpLpo7FUdm6nCfC8NOHzv5gXsTv6CLp9XYgAc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=F475fBXZhtqFUmOdgEFuz5LsdXRGjlEdV9hnOX3u0q4zffKd40aw1WHSsEmRebGL0 ENXqU8qMVoqNdhKrYLtup5joiLUi4xOE1KnCDNFQ3tQ7mDMou+TTaGafh3Jkxf8i7+ u/MSMSMqiIZqKPe8drScC5RC9xOhhhWb5bQSdY3I= From: Arnaldo Carvalho de Melo To: Ingo Molnar , Thomas Gleixner Cc: Jiri Olsa , Namhyung Kim , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Jiri Olsa , Arnaldo Carvalho de Melo , Alexander Shishkin , Ben Gainey , Peter Zijlstra , Stephane Eranian Subject: [PATCH 30/85] perf jvmti: Address gcc string overflow warning for strncpy() Date: Tue, 11 Jun 2019 15:58:16 -0300 Message-Id: <20190611185911.11645-31-acme@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190611185911.11645-1-acme@kernel.org> References: <20190611185911.11645-1-acme@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jiri Olsa We are getting false positive gcc warning when we compile with gcc9 (9.1.1): CC jvmti/libjvmti.o In file included from /usr/include/string.h:494, from jvmti/libjvmti.c:5: In function ‘strncpy’, inlined from ‘copy_class_filename.constprop’ at jvmti/libjvmti.c:166:3: /usr/include/bits/string_fortified.h:106:10: error: ‘__builtin_strncpy’ specified bound depends on the length of the source argument [-Werror=stringop-overflow=] 106 | return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ jvmti/libjvmti.c: In function ‘copy_class_filename.constprop’: jvmti/libjvmti.c:165:26: note: length computed here 165 | size_t file_name_len = strlen(file_name); | ^~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors As per Arnaldo's suggestion use strlcpy(), which does the same thing and keeps gcc silent. Suggested-by: Arnaldo Carvalho de Melo Signed-off-by: Jiri Olsa Cc: Alexander Shishkin Cc: Ben Gainey Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/20190531131321.GB1281@krava Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/jvmti/libjvmti.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/perf/jvmti/libjvmti.c b/tools/perf/jvmti/libjvmti.c index aea7b1fe85aa..c441a34cb1c0 100644 --- a/tools/perf/jvmti/libjvmti.c +++ b/tools/perf/jvmti/libjvmti.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #include +#include #include #include #include @@ -162,8 +163,7 @@ copy_class_filename(const char * class_sign, const char * file_name, char * resu result[i] = '\0'; } else { /* fallback case */ - size_t file_name_len = strlen(file_name); - strncpy(result, file_name, file_name_len < max_length ? file_name_len : max_length); + strlcpy(result, file_name, max_length); } } -- 2.20.1