From patchwork Wed Mar 24 13:19:54 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 12161161 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=-19.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 617AEC433E1 for ; Wed, 24 Mar 2021 13:20:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2509161A14 for ; Wed, 24 Mar 2021 13:20:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234802AbhCXNUS (ORCPT ); Wed, 24 Mar 2021 09:20:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:45452 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234844AbhCXNUD (ORCPT ); Wed, 24 Mar 2021 09:20:03 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id F2FD961A01; Wed, 24 Mar 2021 13:20:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616592003; bh=mGh+44Zfv/STwMBai++b5B0xWcfoJzMizF1R245Y8sI=; h=From:To:Cc:Subject:Date:From; b=YDi0CBM5oo7klqsbp9Ce6UHJoraBrwd9JSr492FtnM3WC19t60MaTVxwLc5EQbVD9 +6aT12A8x5ohAi15GJjwMTaF9IXsNUcbEmdgsJ3TDB7E0m2aa7aKvzRQqXuFxJ4lIn wFRuOVioLNX21EqFm+Y7+l0mTg0qEAaQgFnMXfCe+Nkuijcn9Qwt005luWKnrTRgad AnlC8jMJWs6tZl9fcL226YK1pClMXUz9nUlxSrh0DtjOIGdWqVRd2C/5CNmL8OYOwO 6l/Y9yXk9twcRN+2faAiXR5MJiDGnRTdLP1Q6nZPNiV8mD0TCiFC23zmnBDEuC4YOh xkPJnroTL5AOA== From: Arnd Bergmann To: Dmitry Torokhov Cc: Arnd Bergmann , Rasmus Villemoes , Zhang Qilong , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] [v2] Input: analog - fix invalid snprintf() call Date: Wed, 24 Mar 2021 14:19:54 +0100 Message-Id: <20210324131959.2089129-1-arnd@kernel.org> X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org From: Arnd Bergmann Overlapping input and output arguments to snprintf() are undefined behavior in C99: drivers/input/joystick/analog.c: In function 'analog_name': drivers/input/joystick/analog.c:428:3: error: 'snprintf' argument 4 overlaps destination object 'analog' [-Werror=restrict] 428 | snprintf(analog->name, sizeof(analog->name), "%s %d-hat", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 429 | analog->name, hweight16(analog->mask & ANALOG_HATS_ALL)); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/input/joystick/analog.c:420:40: note: destination object referenced by 'restrict'-qualified argument 1 was declared here 420 | static void analog_name(struct analog *analog) | ~~~~~~~~~~~~~~~^~~~~~ Change this function to use the simpler seq_buf interface instead. Cc: Rasmus Villemoes Signed-off-by: Arnd Bergmann --- v2: use seq_buf instead of rolling my own --- drivers/input/joystick/analog.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/drivers/input/joystick/analog.c b/drivers/input/joystick/analog.c index f798922a4598..087b65ae7585 100644 --- a/drivers/input/joystick/analog.c +++ b/drivers/input/joystick/analog.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include @@ -419,23 +420,24 @@ static void analog_calibrate_timer(struct analog_port *port) static void analog_name(struct analog *analog) { - snprintf(analog->name, sizeof(analog->name), "Analog %d-axis %d-button", + struct seq_buf s; + + seq_buf_init(&s, analog->name, sizeof(analog->name)); + seq_buf_printf(&s, "Analog %d-axis %d-button", hweight8(analog->mask & ANALOG_AXES_STD), hweight8(analog->mask & ANALOG_BTNS_STD) + !!(analog->mask & ANALOG_BTNS_CHF) * 2 + hweight16(analog->mask & ANALOG_BTNS_GAMEPAD) + !!(analog->mask & ANALOG_HBTN_CHF) * 4); if (analog->mask & ANALOG_HATS_ALL) - snprintf(analog->name, sizeof(analog->name), "%s %d-hat", - analog->name, hweight16(analog->mask & ANALOG_HATS_ALL)); + seq_buf_printf(&s, " %d-hat", + hweight16(analog->mask & ANALOG_HATS_ALL)); if (analog->mask & ANALOG_HAT_FCS) - strlcat(analog->name, " FCS", sizeof(analog->name)); + seq_buf_printf(&s, " FCS"); if (analog->mask & ANALOG_ANY_CHF) - strlcat(analog->name, (analog->mask & ANALOG_SAITEK) ? " Saitek" : " CHF", - sizeof(analog->name)); + seq_buf_printf(&s, (analog->mask & ANALOG_SAITEK) ? " Saitek" : " CHF"); - strlcat(analog->name, (analog->mask & ANALOG_GAMEPAD) ? " gamepad": " joystick", - sizeof(analog->name)); + seq_buf_printf(&s, (analog->mask & ANALOG_GAMEPAD) ? " gamepad": " joystick"); } /*