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=-11.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 4635FC433E0 for ; Wed, 8 Jul 2020 07:21:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 205EE20739 for ; Wed, 8 Jul 2020 07:21:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594192891; bh=ZJukO1xQ7tQO3w5sN4dpFvqDoCTnZ8YNDB767EkqG5g=; h=Subject:To:From:Date:List-ID:From; b=U/dryUXRGaBeIZ3b9V0CYpIBxlpAPC8gh7zMDIRa8j95APqlNsUShqjIVPeDGfoWW En+fWLc+DwlrOMJzEDli74Ohz97SIsl/NTgFcRgUAO7P/jsdPy8QeGSvxFoKD42CmC f57RGxb+i2pB3x/8hOpYvBtmZEI2Cwf/UgXequv8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730049AbgGHHVa (ORCPT ); Wed, 8 Jul 2020 03:21:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:45480 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729340AbgGHHVa (ORCPT ); Wed, 8 Jul 2020 03:21:30 -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 77EFD206E2; Wed, 8 Jul 2020 07:21:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594192890; bh=ZJukO1xQ7tQO3w5sN4dpFvqDoCTnZ8YNDB767EkqG5g=; h=Subject:To:From:Date:From; b=pjcogBGIE/B8z+ozeszhAvqwNlJfNYwxC25kaUNXh4srHh5nnP/voBRX9I/sc+lbC us4dKZ3b19urFBpn8yUMsllS+gZ1tN2G7U5QAGinbpTp3eU2W9PzTpp6B2R/O51mPO b3uWMqc7TnNTzxN2iD6q5CZkm2hNiwAkWKnhh6Bk= Subject: patch "iio:health:afe4403 Fix timestamp alignment and prevent data leak." added to staging-linus To: Jonathan.Cameron@huawei.com, Stable@vger.kernel.org, afd@ti.com, lars@metafoo.de From: Date: Wed, 08 Jul 2020 09:21:26 +0200 Message-ID: <1594192886179106@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org 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:health:afe4403 Fix timestamp alignment and prevent data leak. 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-linus 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 hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From 3f9c6d38797e9903937b007a341dad0c251765d6 Mon Sep 17 00:00:00 2001 From: Jonathan Cameron Date: Sun, 17 May 2020 18:29:56 +0100 Subject: iio:health:afe4403 Fix timestamp alignment and prevent data leak. 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 a 32 byte 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 with alignment explicitly requested. This data is allocated with kzalloc so no data can leak appart from previous readings. Fixes: eec96d1e2d31 ("iio: health: Add driver for the TI AFE4403 heart monitor") Reported-by: Lars-Peter Clausen Signed-off-by: Jonathan Cameron Acked-by: Andrew F. Davis Cc: Signed-off-by: Jonathan Cameron --- drivers/iio/health/afe4403.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/iio/health/afe4403.c b/drivers/iio/health/afe4403.c index e9f87e42ff4f..a3507624b30f 100644 --- a/drivers/iio/health/afe4403.c +++ b/drivers/iio/health/afe4403.c @@ -65,6 +65,7 @@ static const struct reg_field afe4403_reg_fields[] = { * @regulator: Pointer to the regulator for the IC * @trig: IIO trigger for this device * @irq: ADC_RDY line interrupt number + * @buffer: Used to construct data layout to push into IIO buffer. */ struct afe4403_data { struct device *dev; @@ -74,6 +75,8 @@ struct afe4403_data { struct regulator *regulator; struct iio_trigger *trig; int irq; + /* Ensure suitable alignment for timestamp */ + s32 buffer[8] __aligned(8); }; enum afe4403_chan_id { @@ -309,7 +312,6 @@ static irqreturn_t afe4403_trigger_handler(int irq, void *private) struct iio_dev *indio_dev = pf->indio_dev; struct afe4403_data *afe = iio_priv(indio_dev); int ret, bit, i = 0; - s32 buffer[8]; u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ}; u8 rx[3]; @@ -326,7 +328,7 @@ static irqreturn_t afe4403_trigger_handler(int irq, void *private) if (ret) goto err; - buffer[i++] = get_unaligned_be24(&rx[0]); + afe->buffer[i++] = get_unaligned_be24(&rx[0]); } /* Disable reading from the device */ @@ -335,7 +337,8 @@ static irqreturn_t afe4403_trigger_handler(int irq, void *private) if (ret) goto err; - iio_push_to_buffers_with_timestamp(indio_dev, buffer, pf->timestamp); + iio_push_to_buffers_with_timestamp(indio_dev, afe->buffer, + pf->timestamp); err: iio_trigger_notify_done(indio_dev->trig); -- 2.27.0