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=-18.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 82E98C4361B for ; Sat, 5 Dec 2020 18:40:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5EAB722E00 for ; Sat, 5 Dec 2020 18:40:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726863AbgLESjn (ORCPT ); Sat, 5 Dec 2020 13:39:43 -0500 Received: from mail.kernel.org ([198.145.29.99]:33370 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726868AbgLESj1 (ORCPT ); Sat, 5 Dec 2020 13:39:27 -0500 Subject: patch "iio:imu:bmi160: Fix alignment and data leak issues" added to staging-next DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1607183281; bh=VWNITlaYuDthc+BL1rv4Xr19W4f+toMoLtt8taoaSSA=; h=To:From:Date:From; b=hsxU2UCa6WKSntpjSPczrURl9AM0JhsoNJKPcDWSbxb5qmI3uQwfV/VB9jHqPjZDh LXzUEz0BMHN4+SemFD4GhXHAgkaiwl1+vykGFcYbrHWlDgXKsd2bN5+uas1e+15bXW i3dkUlb342XcPHHgzEZAm3dIIu65J5cM7SUxBI/Q= To: Jonathan.Cameron@huawei.com, Stable@vger.kernel.org, alexandru.ardelean@analog.com, daniel.baluta@gmail.com, daniel.baluta@oss.nxp.com, lars@metafoo.de From: Date: Sat, 05 Dec 2020 16:46:04 +0100 Message-ID: <160718316415195@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is a note to let you know that I've just added the patch titled iio:imu:bmi160: Fix alignment and data leak issues to my staging git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git in the staging-next branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will also be merged in the next major kernel release during the merge window. If you have any questions about this process, please let me know. >From 7b6b51234df6cd8b04fe736b0b89c25612d896b8 Mon Sep 17 00:00:00 2001 From: Jonathan Cameron Date: Sun, 20 Sep 2020 12:27:39 +0100 Subject: iio:imu:bmi160: Fix alignment and data leak issues 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 array in the iio_priv() data with alignment explicitly requested. This data is allocated with kzalloc() so no data can leak apart from previous readings. In this driver, depending on which channels are enabled, the timestamp can be in a number of locations. Hence we cannot use a structure to specify the data layout without it being misleading. Fixes: 77c4ad2d6a9b ("iio: imu: Add initial support for Bosch BMI160") Reported-by: Lars-Peter Clausen Signed-off-by: Jonathan Cameron Reviewed-by: Alexandru Ardelean Cc: Daniel Baluta Cc: Daniel Baluta Cc: Link: https://lore.kernel.org/r/20200920112742.170751-6-jic23@kernel.org --- drivers/iio/imu/bmi160/bmi160.h | 7 +++++++ drivers/iio/imu/bmi160/bmi160_core.c | 6 ++---- 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/iio/imu/bmi160/bmi160.h b/drivers/iio/imu/bmi160/bmi160.h index a82e040bd109..32c2ea2d7112 100644 --- a/drivers/iio/imu/bmi160/bmi160.h +++ b/drivers/iio/imu/bmi160/bmi160.h @@ -10,6 +10,13 @@ struct bmi160_data { struct iio_trigger *trig; struct regulator_bulk_data supplies[2]; struct iio_mount_matrix orientation; + /* + * Ensure natural alignment for timestamp if present. + * Max length needed: 2 * 3 channels + 4 bytes padding + 8 byte ts. + * If fewer channels are enabled, less space may be needed, as + * long as the timestamp is still aligned to 8 bytes. + */ + __le16 buf[12] __aligned(8); }; extern const struct regmap_config bmi160_regmap_config; diff --git a/drivers/iio/imu/bmi160/bmi160_core.c b/drivers/iio/imu/bmi160/bmi160_core.c index c8e131c29043..290b5ef83f77 100644 --- a/drivers/iio/imu/bmi160/bmi160_core.c +++ b/drivers/iio/imu/bmi160/bmi160_core.c @@ -427,8 +427,6 @@ static irqreturn_t bmi160_trigger_handler(int irq, void *p) struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct bmi160_data *data = iio_priv(indio_dev); - __le16 buf[12]; - /* 2 sens x 3 axis x __le16 + 2 x __le16 pad + 4 x __le16 tstamp */ int i, ret, j = 0, base = BMI160_REG_DATA_MAGN_XOUT_L; __le16 sample; @@ -438,10 +436,10 @@ static irqreturn_t bmi160_trigger_handler(int irq, void *p) &sample, sizeof(sample)); if (ret) goto done; - buf[j++] = sample; + data->buf[j++] = sample; } - iio_push_to_buffers_with_timestamp(indio_dev, buf, pf->timestamp); + iio_push_to_buffers_with_timestamp(indio_dev, data->buf, pf->timestamp); done: iio_trigger_notify_done(indio_dev->trig); return IRQ_HANDLED; -- 2.29.2