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Date:   Tue, 29 Aug 2023 11:09:18 +0800
From:   Tzung-Bi Shih <tzungbi@kernel.org>
To:     Jonathan Cameron <jic23@kernel.org>
Cc:     bleung@chromium.org, groeck@chromium.org, lars@metafoo.de,
        chrome-platform@lists.linux.dev, gwendal@chromium.org,
        linux-iio@vger.kernel.org, dianders@chromium.org,
        swboyd@chromium.org, stable@vger.kernel.org
Subject: Re: [PATCH] iio: cros_ec: fix an use-after-free in
 cros_ec_sensors_push_data()
Message-ID: <ZO1hXo7J02w8sv0T@google.com>
References: <20230828094339.1248472-1-tzungbi@kernel.org>
 <20230828115359.054dc13a@jic23-huawei>
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On Mon, Aug 28, 2023 at 11:53:59AM +0100, Jonathan Cameron wrote:
> Can we use iio_device_claim_buffer_mode() here?  I believe that has the right handling
> even though I don't think we've used it to protect iio_push_* before.  Normally it's about
> enforcing we stay in the mode if the read out of a channel needs to be handled differently
> in a read_raw() callback.
> 
> if (iio_device_claim_buffer_mode(indio_dev) < 0) {
> 	/* Not in buffer mode so fine to drop out - we got -EBUSY*/
> 	return 0;
> }
> //Otherwise mlock is held - though that's an implementation detail all we care about is we can't exit buffer mode.
> ...
> iio_push_...
> iio_device_release_buffer_mode(indio_dev);
> return 0;

Ack, fix it in v2(https://patchwork.kernel.org/project/linux-iio/patch/20230829030622.1571852-1-tzungbi@kernel.org/).