From patchwork Thu May 20 11:15:52 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Colin King X-Patchwork-Id: 445286 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, USER_AGENT_GIT autolearn=unavailable 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 F3998C43470 for ; Thu, 20 May 2021 11:18:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D6B0C613AD for ; Thu, 20 May 2021 11:18:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239566AbhETLUJ (ORCPT ); Thu, 20 May 2021 07:20:09 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:34531 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240136AbhETLRQ (ORCPT ); Thu, 20 May 2021 07:17:16 -0400 Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.93) (envelope-from ) id 1ljgee-0006Fj-BN; Thu, 20 May 2021 11:15:52 +0000 From: Colin King To: Greg Kroah-Hartman Cc: kernel-janitors@vger.kernel.org, Stable@vger.kernel.org, Nobuhiro Iwamatsu Subject: [PATCH][4.9.y] iio: tsl2583: Fix division by a zero lux_val Date: Thu, 20 May 2021 12:15:52 +0100 Message-Id: <20210520111552.27409-1-colin.king@canonical.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Colin Ian King commit af0e1871d79cfbb91f732d2c6fa7558e45c31038 upstream. The lux_val returned from tsl2583_get_lux can potentially be zero, so check for this to avoid a division by zero and an overflowed gain_trim_val. Fixes clang scan-build warning: drivers/iio/light/tsl2583.c:345:40: warning: Either the condition 'lux_val<0' is redundant or there is division by zero at line 345. [zerodivcond] Fixes: ac4f6eee8fe8 ("staging: iio: TAOS tsl258x: Device driver") Signed-off-by: Colin Ian King Cc: Signed-off-by: Jonathan Cameron [iwamatsu: Change file path.] [Colin Ian King: minor context adjustments for 4.9.y] Signed-off-by: Nobuhiro Iwamatsu --- drivers/staging/iio/light/tsl2583.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/staging/iio/light/tsl2583.c b/drivers/staging/iio/light/tsl2583.c index 08f1583ee34e..fb3ec56d45b6 100644 --- a/drivers/staging/iio/light/tsl2583.c +++ b/drivers/staging/iio/light/tsl2583.c @@ -382,6 +382,15 @@ static int taos_als_calibrate(struct iio_dev *indio_dev) dev_err(&chip->client->dev, "taos_als_calibrate failed to get lux\n"); return lux_val; } + + /* Avoid division by zero of lux_value later on */ + if (lux_val == 0) { + dev_err(&chip->client->dev, + "%s: lux_val of 0 will produce out of range trim_value\n", + __func__); + return -ENODATA; + } + gain_trim_val = (unsigned int)(((chip->taos_settings.als_cal_target) * chip->taos_settings.als_gain_trim) / lux_val);