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=-8.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_2 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 EB3DEC352AA for ; Tue, 1 Oct 2019 08:54:57 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BE33F21906 for ; Tue, 1 Oct 2019 08:54:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="JN0aWKE7"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="Dw4H4ZgG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BE33F21906 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=xy58vScJSWMhSpWYamuN2NKUYHpu2rdxemaox3gjGew=; b=JN0aWKE7yd1efJ 02ieUl1FUBajq3tneBJuF5wNuWaj4JsIWGE4N3B5/Esrye1ctuAMnkqCX2bBIqQTxOjZ1DdCwe8Pr W9WU5mDzIZrd/0GgBamJgyzlS3vwRdkICS0CHT3A+HBDMjRaBB0kagGdjLUDJvJ1IOVmZu7sS4clD UCUTSWAs7H0W+fYpXFkOLYqUMkotMAXWC6jOJclMvWviaaXlwsYCHp4AjpcZjVMYHkzdsODuYAFcb 12XBJzHmHsb3qoZ8AgyxbOt2SBM2k4IGSVv2N1qnGuNuM/wa5f7l8MC4myQnOMtNOFK127Ff0ILaR JKWvosX2Dxb6sP+JFIQw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iFDvs-00012i-S2; Tue, 01 Oct 2019 08:54:56 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.2 #3 (Red Hat Linux)) id 1iFDvp-00012M-T5 for linux-arm-kernel@lists.infradead.org; Tue, 01 Oct 2019 08:54:55 +0000 Received: from archlinux (cpc149474-cmbg20-2-0-cust94.5-4.cable.virginm.net [82.4.196.95]) (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 D4E4F2133F; Tue, 1 Oct 2019 08:54:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569920093; bh=szecxbNIyt9fQKdI3mGXWWqH6xc6Il8EeHjy2q22MmE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Dw4H4ZgGHfx/ZI6u+yBi43GwHZD0pDN+dtBIoa/0toBp0bJaCpdYHjNkGLCFAI9sf p885axzz4B5SVa572ab3PX675xVLqnNifp3CrsKEnCpiFERdRAknYwkpPY5g2i7kq1 M36qcriDMmumSxbNIUz0jbiLSTvWluo3nA59W9Xg= Date: Tue, 1 Oct 2019 09:54:46 +0100 From: Jonathan Cameron To: Marco Felsch Subject: Re: [PATCH] iio: adc: imx25-gcq: Variable could be uninitialized if regmap_read() fails Message-ID: <20191001095446.17bc9cd8@archlinux> In-Reply-To: <20190930074412.up4k6zdus4y7u4xb@pengutronix.de> References: <20190928002852.28329-1-yzhai003@ucr.edu> <20190930074412.up4k6zdus4y7u4xb@pengutronix.de> X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191001_015453_979935_5539701E X-CRM114-Status: GOOD ( 24.78 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: csong@cs.ucr.edu, Kate Stewart , Lars-Peter Clausen , Peter Meerwald-Stadler , linux-iio@vger.kernel.org, Greg Kroah-Hartman , Sascha Hauer , zhiyunq@cs.ucr.edu, linux-kernel@vger.kernel.org, Fabio Estevam , Yizhuo , NXP Linux Team , Pengutronix Kernel Team , Hartmut Knaack , Shawn Guo , Thomas Gleixner , Enrico Weigelt , Allison Randal , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, 30 Sep 2019 09:44:12 +0200 Marco Felsch wrote: > Hi Yizhuo, > > thanks for your patch. > > On 19-09-27 17:28, Yizhuo wrote: > > In function mx25_gcq_irq(), local variable "stats" could > > be uninitialized if function regmap_read() returns -EINVAL. > > However, this value is used in if statement, which is > > potentially unsafe. The same case applied to the variable > > "data" in function mx25_gcq_get_raw_value() in the same file. > > IMHO the commit header should be something like: "iio: adc: imx25-gcq: > fix uninitialized variable usage"... > > and please add a fixes tag. As with the others, before adding a fixes tag, please verify there is an actual path to trigger this. In this case it's an mmio regmap with no clock. For those, I'm not sure if there is a failure path. Still a worthwhile hardening / cleanup patch, but shouldn't be called a fix or marked with a fixes tag because we don't want people to think it is necessary to backport it. Thanks, Jonathan > > > > > Signed-off-by: Yizhuo > > --- > > drivers/iio/adc/fsl-imx25-gcq.c | 10 ++++++++-- > > 1 file changed, 8 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/iio/adc/fsl-imx25-gcq.c b/drivers/iio/adc/fsl-imx25-gcq.c > > index df19ecae52f7..dbf3e8e85aba 100644 > > --- a/drivers/iio/adc/fsl-imx25-gcq.c > > +++ b/drivers/iio/adc/fsl-imx25-gcq.c > > @@ -74,7 +74,10 @@ static irqreturn_t mx25_gcq_irq(int irq, void *data) > > struct mx25_gcq_priv *priv = data; > > u32 stats; > > > > - regmap_read(priv->regs, MX25_ADCQ_SR, &stats); > > + int ret = regmap_read(priv->regs, MX25_ADCQ_SR, &stats); > > Please don't do this. First declare the variable and then use it. > > Regards, > Marco > > > + > > + if (ret) > > + return ret; > > > > if (stats & MX25_ADCQ_SR_EOQ) { > > regmap_update_bits(priv->regs, MX25_ADCQ_MR, > > @@ -121,7 +124,10 @@ static int mx25_gcq_get_raw_value(struct device *dev, > > return -ETIMEDOUT; > > } > > > > - regmap_read(priv->regs, MX25_ADCQ_FIFO, &data); > > + int ret = regmap_read(priv->regs, MX25_ADCQ_FIFO, &data); > > + > > + if (ret) > > + return ret; > > > > *val = MX25_ADCQ_FIFO_DATA(data); > > > > -- > > 2.17.1 > > > > > > > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel