Re: [PATCH 2/3] iio: adc: xilinx: fix potential use-after-free on probe

From: Jonathan Cameron
Date: Sat Mar 16 2019 - 11:49:31 EST


On Sun, 10 Mar 2019 14:58:25 -0400
Sven Van Asbroeck <thesven73@xxxxxxxxx> wrote:

> If probe errors out after request_irq(), its error path
> does not explicitly cancel the delayed work, which may
> have been scheduled by the interrupt handler.
>
> This means the delayed work may still be running when
> the core frees the private structure (struct xadc).
> This is a potential use-after-free.
>
> Fix by inserting cancel_delayed_work_sync() in the probe
> error path.
>
> Signed-off-by: Sven Van Asbroeck <TheSven73@xxxxxxxxx>
Again, seems fine to me.

Applied to the fixes-togreg branch of iio.git.

thanks,

Jonathan

> ---
> drivers/iio/adc/xilinx-xadc-core.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/iio/adc/xilinx-xadc-core.c b/drivers/iio/adc/xilinx-xadc-core.c
> index 1960694e8007..15e1a103f37d 100644
> --- a/drivers/iio/adc/xilinx-xadc-core.c
> +++ b/drivers/iio/adc/xilinx-xadc-core.c
> @@ -1290,6 +1290,7 @@ static int xadc_probe(struct platform_device *pdev)
>
> err_free_irq:
> free_irq(xadc->irq, indio_dev);
> + cancel_delayed_work_sync(&xadc->zynq_unmask_work);
> err_clk_disable_unprepare:
> clk_disable_unprepare(xadc->clk);
> err_free_samplerate_trigger: