From patchwork Mon Jul 20 15:35:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 237549 Delivered-To: patch@linaro.org Received: by 2002:a92:d244:0:0:0:0:0 with SMTP id v4csp2132675ilg; Mon, 20 Jul 2020 09:31:32 -0700 (PDT) X-Google-Smtp-Source: ABdhPJy54QrqtNoj3g52NMf6VgeXHGQkMv1TVnezT8YlLS1cmll0V20amMOfkEkB+gDhqJ5gWJYa X-Received: by 2002:a05:6402:203c:: with SMTP id ay28mr22772829edb.271.1595262692327; Mon, 20 Jul 2020 09:31:32 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1595262692; cv=none; d=google.com; s=arc-20160816; b=MbL4TZ+YEYQXiJWPnT1NEQxkkmlw8H8cYCpTtc3NXWQ4N0LhHF/ZJH25+qI4unEyVn 3ZZ10r9nyjhmXJaLV7jSlHjEN+XAL6jTqOqgDXy8W7GooqFFUcoT3BVwAkaK7znmt+L9 STIS5OfsyYHO91+qEm6Rh1K06pJcCPtRR1gIG4GjR+T05oaG1HCeMuH9vIsmLOGOt6kn l3Ih6quK58PREdJniJfaqJirwRpVP5KshsN6s8tj6tR3z5mQHqyHNPzDRxyFOfwyYviJ YOPy8/cxxc7Mjkq9ujp+j2u4mRetdsWFW1C3dEPiBRydmj5HXfU6VjG23w74mXHJubSb f1Dg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=l8KnzwoKf7gRZ0Fx41brVh3Q/lLjum33UsNQCpM7H/I=; b=iRXBL5eUKeEtLSBa1GpMnSJbU7yX68oq9CHjLBhfaOZStK6MY4vJ3lEb1CpQ1CrYq9 JL+YfnrHBtoEm0tF/yoiE+lNFUd3gkzz6VYDXddONQ79KhAF0M6hvHLVdZGrBjy4UMZq wnaRUedhNmaCmBbElfu4N+Dqhci6UL43+jRTkQU46I2eS/XFVG756fGx7QiAFY/WlA28 ZVWpHB1H7hc0CoFTRs42qRLhnVxn+3DRBMzDy4UsQodTYyoYK1tleW1UC1LdCA3iTD2c JVY3QTCwoPp5SCPPf5XLt6fb6Apb9UwWNLOzoSmsH1v+ByyM9V3AMedLc7NGShBC7Z5V Kp8w== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=VWZVSjHT; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id a1si11610097edb.90.2020.07.20.09.31.18; Mon, 20 Jul 2020 09:31:32 -0700 (PDT) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=VWZVSjHT; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731472AbgGTP5h (ORCPT + 15 others); Mon, 20 Jul 2020 11:57:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:57516 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731931AbgGTP5f (ORCPT ); Mon, 20 Jul 2020 11:57:35 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 975402065E; Mon, 20 Jul 2020 15:57:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595260655; bh=bYcsp+lTAjYQXjg17ZAbSyfn2+pSwrVpblngizYvBnQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VWZVSjHT+Ox6f8Qrs/+/CsGP1r6Ly9IMKzL3mimIB3eDE/50fqiIQo6fMMTnsH6SE v+nk37paGQ0MNhHb4qPZ4n9RNY3V7uoADGCu1F3VNDttEi9hQpRII4UXBYOV4mTEr0 cxlOpIAsUzkVLi4+qCz+0mIYgqMuMPekt7jf6f0U= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lars-Peter Clausen , Matt Ranostay , Alison Schofield , Jonathan Cameron , Stable@vger.kernel.org Subject: [PATCH 5.4 047/215] iio:humidity:hdc100x Fix alignment and data leak issues Date: Mon, 20 Jul 2020 17:35:29 +0200 Message-Id: <20200720152822.437100100@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200720152820.122442056@linuxfoundation.org> References: <20200720152820.122442056@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jonathan Cameron commit ea5e7a7bb6205d24371373cd80325db1bc15eded upstream. One of a class of bugs pointed out by Lars in a recent review. iio_push_to_buffers_with_timestamp assumes the buffer used is aligned to the size of the timestamp (8 bytes). This is not guaranteed in this driver which uses an array of smaller elements on the stack. As Lars also noted this anti pattern can involve a leak of data to userspace and that indeed can happen here. We close both issues by moving to a suitable structure in the iio_priv() data. This data is allocated with kzalloc so no data can leak apart from previous readings. Fixes: 16bf793f86b2 ("iio: humidity: hdc100x: add triggered buffer support for HDC100X") Reported-by: Lars-Peter Clausen Acked-by: Matt Ranostay Cc: Alison Schofield Signed-off-by: Jonathan Cameron Cc: Signed-off-by: Greg Kroah-Hartman --- drivers/iio/humidity/hdc100x.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) --- a/drivers/iio/humidity/hdc100x.c +++ b/drivers/iio/humidity/hdc100x.c @@ -38,6 +38,11 @@ struct hdc100x_data { /* integration time of the sensor */ int adc_int_us[2]; + /* Ensure natural alignment of timestamp */ + struct { + __be16 channels[2]; + s64 ts __aligned(8); + } scan; }; /* integration time in us */ @@ -319,7 +324,6 @@ static irqreturn_t hdc100x_trigger_handl struct i2c_client *client = data->client; int delay = data->adc_int_us[0] + data->adc_int_us[1]; int ret; - s16 buf[8]; /* 2x s16 + padding + 8 byte timestamp */ /* dual read starts at temp register */ mutex_lock(&data->lock); @@ -330,13 +334,13 @@ static irqreturn_t hdc100x_trigger_handl } usleep_range(delay, delay + 1000); - ret = i2c_master_recv(client, (u8 *)buf, 4); + ret = i2c_master_recv(client, (u8 *)data->scan.channels, 4); if (ret < 0) { dev_err(&client->dev, "cannot read sensor data\n"); goto err; } - iio_push_to_buffers_with_timestamp(indio_dev, buf, + iio_push_to_buffers_with_timestamp(indio_dev, &data->scan, iio_get_time_ns(indio_dev)); err: mutex_unlock(&data->lock);