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 C5CA0C433F5 for ; Thu, 28 Apr 2022 18:33:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351095AbiD1Sgj (ORCPT ); Thu, 28 Apr 2022 14:36:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351025AbiD1Sgh (ORCPT ); Thu, 28 Apr 2022 14:36:37 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DEBBCBC857; Thu, 28 Apr 2022 11:33:21 -0700 (PDT) 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 8AA76B82F54; Thu, 28 Apr 2022 18:33:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1B5DDC385A0; Thu, 28 Apr 2022 18:33:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1651170799; bh=dM6SoIhKU87s7JyFiu8ZaRPnKv0+Vb1zN0hW0z5OG5U=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=kBe2CEqMcaaLxZcAjYt6vzZWMJD+jUyZPbBKlES+nEdUFKobJonRu4HypAsL/Tt8h 4iWPDrRlh/zcEIttBC8kAdR91hyTxH61nHkw1asz5tA9OsMuTW1fiFTWXSkIqVYSjY j0MB3+LuXlxmAQa+teNK532AqlqUWSHb00p6Bq94kNSCEB50i4vToMcgi9WIuc4NeV I9yzYD+YSAcl7JU0F/hLUqf1ZXsMdtHH24Cv/aNhFBlvfF6g4I/qOD6JGrwOq+UYvi dD+u993ZT3OOJR4ICzWlr2/9HU7fVSkq4X6UjwinMGwO/tDl4U3rYnI5Dsl/HnEbGN B6iT8jqh7bPQg== Date: Thu, 28 Apr 2022 19:41:32 +0100 From: Jonathan Cameron To: Haowen Bai Cc: Lars-Peter Clausen , , Subject: Re: [PATCH V3] iio: gp2ap020a00f: Fix signedness bug Message-ID: <20220428194132.5a02555c@jic23-huawei> In-Reply-To: <1650248375-6334-1-git-send-email-baihaowen@meizu.com> References: <20220415185205.26a3d352@jic23-huawei> <1650248375-6334-1-git-send-email-baihaowen@meizu.com> X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 18 Apr 2022 10:19:35 +0800 Haowen Bai wrote: > function gp2ap020a00f_get_thresh_reg() is unsigned but returning -EINVAL > errcode, and thresh_reg_l is unsigned but receiving -EINVAL errcode. so > we have to change u8 -> int. Also we need to do index bound check at > gp2ap020a00f_read_event_val(). > > Signed-off-by: Haowen Bai Please add a Fixes tag if possible. > --- > V1->V2: s8 is not enough to hold an (arbitrary) error code. To be on the safe > side we need to use int. > V2->V3: add bound check at gp2ap020a00f_read_event_val(). > > > drivers/iio/light/gp2ap020a00f.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/iio/light/gp2ap020a00f.c b/drivers/iio/light/gp2ap020a00f.c > index b820041159f7..f80d30786035 100644 > --- a/drivers/iio/light/gp2ap020a00f.c > +++ b/drivers/iio/light/gp2ap020a00f.c > @@ -994,7 +994,7 @@ static irqreturn_t gp2ap020a00f_trigger_handler(int irq, void *data) > return IRQ_HANDLED; > } > > -static u8 gp2ap020a00f_get_thresh_reg(const struct iio_chan_spec *chan, > +static int gp2ap020a00f_get_thresh_reg(const struct iio_chan_spec *chan, > enum iio_event_direction event_dir) > { > switch (chan->type) { > @@ -1025,7 +1025,7 @@ static int gp2ap020a00f_write_event_val(struct iio_dev *indio_dev, > struct gp2ap020a00f_data *data = iio_priv(indio_dev); > bool event_en = false; > u8 thresh_val_id; > - u8 thresh_reg_l; > + int thresh_reg_l; You need to check this val after the function call, but before it is used. > int err = 0; > > mutex_lock(&data->lock); > @@ -1082,14 +1082,14 @@ static int gp2ap020a00f_read_event_val(struct iio_dev *indio_dev, > int *val, int *val2) > { > struct gp2ap020a00f_data *data = iio_priv(indio_dev); > - u8 thresh_reg_l; > + int thresh_reg_l; > int err = IIO_VAL_INT; > > mutex_lock(&data->lock); > > thresh_reg_l = gp2ap020a00f_get_thresh_reg(chan, dir); > > - if (thresh_reg_l > GP2AP020A00F_PH_L_REG) { > + if (thresh_reg_l < 0 || thresh_reg_l > GP2AP020A00F_PH_L_REG) { > err = -EINVAL; If a function returns an error we should pass that on unchanged Here the value is the same, but none the less we should have this look something like. if (thresh_reg_l < 0) return thresh_reg_l; if (thresh_reg_l > GP2AP020A00F_PH_L_REG) ... > goto error_unlock; > }