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 EBC1DC433F5 for ; Sat, 12 Mar 2022 23:26:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232578AbiCLX1g (ORCPT ); Sat, 12 Mar 2022 18:27:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37670 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231277AbiCLX1D (ORCPT ); Sat, 12 Mar 2022 18:27:03 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 358699398A for ; Sat, 12 Mar 2022 15:25:55 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 0A144B80B36 for ; Sat, 12 Mar 2022 23:25:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A36D0C340F6; Sat, 12 Mar 2022 23:25:52 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.95) (envelope-from ) id 1nTB7P-000WhR-NR; Sat, 12 Mar 2022 18:25:51 -0500 Message-ID: <20220312232551.559953567@goodmis.org> User-Agent: quilt/0.66 Date: Sat, 12 Mar 2022 18:25:34 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , kernel test robot , Tom Zanussi Subject: [for-next][PATCH 09/12] tracing: Fix strncpy warning in trace_events_synth.c References: <20220312232525.234705244@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tom Zanussi 0-day reported the strncpy error below: ../kernel/trace/trace_events_synth.c: In function 'last_cmd_set': ../kernel/trace/trace_events_synth.c:65:9: warning: 'strncpy' specified bound depends on the length o\ f the source argument [-Wstringop-truncation] 65 | strncpy(last_cmd, str, strlen(str) + 1); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ../kernel/trace/trace_events_synth.c:65:32: note: length computed here 65 | strncpy(last_cmd, str, strlen(str) + 1); | ^~~~~~~~~~~ There's no reason to use strncpy here, in fact there's no reason to do anything but a simple kstrdup() (note we don't even need to check for failure since last_cmod is expected to be either the last cmd string or NULL, and the containing function is a void return). Link: https://lkml.kernel.org/r/77deca8cbfd226981b3f1eab203967381e9b5bd9.camel@kernel.org Fixes: 27c888da9867 ("tracing: Remove size restriction on synthetic event cmd error logging") Reported-by: kernel test robot Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_events_synth.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index fdd79e07e2fc..5e8c07aef071 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -58,11 +58,8 @@ static void last_cmd_set(const char *str) return; kfree(last_cmd); - last_cmd = kzalloc(strlen(str) + 1, GFP_KERNEL); - if (!last_cmd) - return; - strncpy(last_cmd, str, strlen(str) + 1); + last_cmd = kstrdup(str, GFP_KERNEL); } static void synth_err(u8 err_type, u16 err_pos) -- 2.35.1