linux-kernel - Re: [PATCH v2 1/5] iio:accel:bma180: rearrange iio trigger get and register

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAHp75Vdyk0228iPX+-D12DcogS0mDBNzUmjAaO=VGT6brH0eyQ@mail.gmail.com>
Date:   Tue, 24 May 2022 21:53:32 +0200
From:   Andy Shevchenko <andy.shevchenko@...il.com>
To:     Dmitry Rokosov <DDRokosov@...rdevices.ru>
Cc:     "robh+dt@...nel.org" <robh+dt@...nel.org>,
        "jic23@...nel.org" <jic23@...nel.org>,
        "lars@...afoo.de" <lars@...afoo.de>,
        "lorenzo.bianconi83@...il.com" <lorenzo.bianconi83@...il.com>,
        "srinivas.pandruvada@...ux.intel.com" 
        <srinivas.pandruvada@...ux.intel.com>,
        "teodora.baluta@...el.com" <teodora.baluta@...el.com>,
        "narcisaanamaria12@...il.com" <narcisaanamaria12@...il.com>,
        "linux-iio@...r.kernel.org" <linux-iio@...r.kernel.org>,
        kernel <kernel@...rdevices.ru>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2 1/5] iio:accel:bma180: rearrange iio trigger get and register

On Tue, May 24, 2022 at 8:14 PM Dmitry Rokosov <DDRokosov@...rdevices.ru> wrote:
>
> IIO trigger interface function iio_trigger_get() should be called after
> iio_trigger_register() (or its devm analogue) strictly, because of
> iio_trigger_get() acquires module refcnt based on the trigger->owner
> pointer, which is initialized inside iio_trigger_register() to
> THIS_MODULE.
> If this call order is wrong, the next iio_trigger_put() (from sysfs
> callback or "delete module" path) will dereference "default" module
> refcnt, which is incorrect behaviour.

Reviewed-by: Andy Shevchenko <andy.shevchenko@...il.com>

> Fixes: 0668a4e4d297 ("iio: accel: bma180: Fix indio_dev->trig assignment")
> Signed-off-by: Dmitry Rokosov <ddrokosov@...rdevices.ru>
> ---
>  drivers/iio/accel/bma180.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iio/accel/bma180.c b/drivers/iio/accel/bma180.c
> index d8a454c266d5..5d0bd0fc3018 100644
> --- a/drivers/iio/accel/bma180.c
> +++ b/drivers/iio/accel/bma180.c
> @@ -1006,11 +1006,12 @@ static int bma180_probe(struct i2c_client *client,
>
>                 data->trig->ops = &bma180_trigger_ops;
>                 iio_trigger_set_drvdata(data->trig, indio_dev);
> -               indio_dev->trig = iio_trigger_get(data->trig);
>
>                 ret = iio_trigger_register(data->trig);
>                 if (ret)
>                         goto err_trigger_free;
> +
> +               indio_dev->trig = iio_trigger_get(data->trig);
>         }
>
>         ret = iio_triggered_buffer_setup(indio_dev, NULL,
> --
> 2.36.0



-- 
With Best Regards,
Andy Shevchenko