linux-iio.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jonathan Cameron <jic23@kernel.org>
To: linux-iio@vger.kernel.org
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>,
	Lars-Peter Clausen <lars@metafoo.de>,
	Peter Meerwald <pmeerw@pmeerw.net>,
	Jonathan Cameron <Jonathan.Cameron@huawei.com>
Subject: Re: [PATCH v3 04/27] iio:accel:mma7455: Fix timestamp alignment and prevent data leak.
Date: Sun, 9 Aug 2020 18:19:12 +0100	[thread overview]
Message-ID: <20200809181912.59839046@archlinux> (raw)
In-Reply-To: <20200722155103.979802-5-jic23@kernel.org>

On Wed, 22 Jul 2020 16:50:40 +0100
Jonathan Cameron <jic23@kernel.org> wrote:

> From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> 
> 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 16 byte u8 array 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
> ensured by use of an explicit c structure.  This data is allocated
> with kzalloc so no data can leak appart from previous readings.
> 
> The force alignment of ts is not strictly necessary in this particularly
> case but does make the code less fragile.
> 
> Fixes: a84ef0d181d9 ("iio: accel: add Freescale MMA7455L/MMA7456L 3-axis accelerometer driver")
> Reported-by: Lars-Peter Clausen <lars@metafoo.de>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Applied to the fixes-togreg branch of iio.git and marked for stable.

Thanks,

Jonathan

> ---
>  drivers/iio/accel/mma7455_core.c | 16 ++++++++++++----
>  1 file changed, 12 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/iio/accel/mma7455_core.c b/drivers/iio/accel/mma7455_core.c
> index 7e99bcb3398d..922bd38ff6ea 100644
> --- a/drivers/iio/accel/mma7455_core.c
> +++ b/drivers/iio/accel/mma7455_core.c
> @@ -52,6 +52,14 @@
>  
>  struct mma7455_data {
>  	struct regmap *regmap;
> +	/*
> +	 * Used to reorganize data.  Will ensure correct alignment of
> +	 * the timestamp if present
> +	 */
> +	struct {
> +		__le16 channels[3];
> +		s64 ts __aligned(8);
> +	} scan;
>  };
>  
>  static int mma7455_drdy(struct mma7455_data *mma7455)
> @@ -82,19 +90,19 @@ static irqreturn_t mma7455_trigger_handler(int irq, void *p)
>  	struct iio_poll_func *pf = p;
>  	struct iio_dev *indio_dev = pf->indio_dev;
>  	struct mma7455_data *mma7455 = iio_priv(indio_dev);
> -	u8 buf[16]; /* 3 x 16-bit channels + padding + ts */
>  	int ret;
>  
>  	ret = mma7455_drdy(mma7455);
>  	if (ret)
>  		goto done;
>  
> -	ret = regmap_bulk_read(mma7455->regmap, MMA7455_REG_XOUTL, buf,
> -			       sizeof(__le16) * 3);
> +	ret = regmap_bulk_read(mma7455->regmap, MMA7455_REG_XOUTL,
> +			       mma7455->scan.channels,
> +			       sizeof(mma7455->scan.channels));
>  	if (ret)
>  		goto done;
>  
> -	iio_push_to_buffers_with_timestamp(indio_dev, buf,
> +	iio_push_to_buffers_with_timestamp(indio_dev, &mma7455->scan,
>  					   iio_get_time_ns(indio_dev));
>  
>  done:


  reply	other threads:[~2020-08-09 17:19 UTC|newest]

Thread overview: 72+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-22 15:50 [PATCH v3 00/27] IIO: Fused set 1 and 2 of timestamp alignment fixes Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 01/27] iio: accel: kxsd9: Fix alignment of local buffer Jonathan Cameron
2020-08-09 17:07   ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 02/27] iio:accel:mma8452: Fix timestamp alignment and prevent data leak Jonathan Cameron
2020-08-09 17:14   ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 03/27] iio:accel:bmc150-accel: " Jonathan Cameron
2020-07-29 17:12   ` Srinivas Pandruvada
2020-08-09 17:18     ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 04/27] iio:accel:mma7455: " Jonathan Cameron
2020-08-09 17:19   ` Jonathan Cameron [this message]
2020-07-22 15:50 ` [PATCH v3 05/27] iio:gyro:itg3200: " Jonathan Cameron
2020-09-19 15:41   ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 06/27] iio:proximity:mb1232: " Jonathan Cameron
2020-08-09 17:20   ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 07/27] iio:chemical:ccs811: " Jonathan Cameron
2020-08-09 17:23   ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 08/27] iio:light:si1145: " Jonathan Cameron
2020-07-22 19:43   ` Andy Shevchenko
2020-07-22 19:45     ` Andy Shevchenko
2020-07-23 11:25       ` Jonathan Cameron
2020-09-19 15:46         ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 09/27] iio:light:max44000 " Jonathan Cameron
2020-08-09 17:24   ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 10/27] iio:light:rpr0521 " Jonathan Cameron
2020-07-22 19:47   ` Andy Shevchenko
2020-07-23 11:29     ` Jonathan Cameron
2020-09-19 16:31       ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 11/27] iio:light:st_uvis25 " Jonathan Cameron
2020-07-22 19:48   ` Andy Shevchenko
2020-07-22 15:50 ` [PATCH v3 12/27] iio:light:ltr501 Fix timestamp alignment issue Jonathan Cameron
2020-08-09 17:27   ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 13/27] iio:magnetometer:ak8975 Fix alignment and data leak issues Jonathan Cameron
2020-08-09 17:30   ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 14/27] iio:magnetometer:mag3110 " Jonathan Cameron
2020-07-23 12:13   ` Andy Shevchenko
2020-07-22 15:50 ` [PATCH v3 15/27] iio:imu:bmi160 " Jonathan Cameron
2020-09-19 15:58   ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 16/27] iio:imu:st_lsm6dsx " Jonathan Cameron
2020-09-19 16:09   ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 17/27] iio:imu:inv_mpu6050 Fix dma and ts " Jonathan Cameron
2020-07-24  8:27   ` Jean-Baptiste Maneyrol
2020-09-19 16:51     ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 18/27] iio:imu:inv_mpu6050: Use regmap_noinc_read for fifo reads Jonathan Cameron
2020-07-23 12:15   ` Andy Shevchenko
2020-07-23 12:28     ` Jonathan Cameron
2020-07-24  8:29   ` Jean-Baptiste Maneyrol
2020-09-19 16:55     ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 19/27] iio:pressure:mpl3115 Force alignment of buffer Jonathan Cameron
2020-07-23 12:17   ` Andy Shevchenko
2020-07-23 12:31     ` Jonathan Cameron
2020-09-19 17:02       ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 20/27] iio:adc:ti-adc081c Fix alignment and data leak issues Jonathan Cameron
2020-08-09 17:34   ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 21/27] iio:adc:ti-adc084s021 " Jonathan Cameron
2020-08-09 17:36   ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 22/27] iio:adc:ti-adc084s021 Tidy up endian types Jonathan Cameron
2020-08-09 17:47   ` Jonathan Cameron
2020-09-13 12:01     ` Jonathan Cameron
2020-09-13 12:06       ` Jonathan Cameron
2020-11-29 13:28         ` Jonathan Cameron
2020-07-22 15:50 ` [PATCH v3 23/27] iio:adc:ti-ads124s08 Fix alignment and data leak issues Jonathan Cameron
2020-07-22 20:54   ` Andy Shevchenko
2020-07-23 11:23     ` Jonathan Cameron
2020-07-22 15:51 ` [PATCH v3 24/27] iio:adc:ti-adc0832 Fix alignment issue with timestamp Jonathan Cameron
2020-09-19 16:18   ` Jonathan Cameron
2020-07-22 15:51 ` [PATCH v3 25/27] iio:adc:ti-adc12138 " Jonathan Cameron
2020-09-19 16:21   ` Jonathan Cameron
2020-07-22 15:51 ` [PATCH v3 26/27] iio:adc:ina2xx Fix timestamp alignment issue Jonathan Cameron
2020-08-09 17:38   ` Jonathan Cameron
2020-07-22 15:51 ` [PATCH v3 27/27] iio:adc:max1118 Fix alignment of timestamp and data leak issues Jonathan Cameron
2020-08-09 17:39   ` Jonathan Cameron
2020-07-23 12:23 ` [PATCH v3 00/27] IIO: Fused set 1 and 2 of timestamp alignment fixes Andy Shevchenko

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200809181912.59839046@archlinux \
    --to=jic23@kernel.org \
    --cc=Jonathan.Cameron@huawei.com \
    --cc=andy.shevchenko@gmail.com \
    --cc=lars@metafoo.de \
    --cc=linux-iio@vger.kernel.org \
    --cc=pmeerw@pmeerw.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).