Re: [PATCH v2 1/2] iio: sca3000: Fix an error handling path in 'sca3000_probe()'

From: Jonathan Cameron
Date: Sun Apr 15 2018 - 15:18:07 EST


On Sun, 8 Apr 2018 21:44:01 +0200
Christophe JAILLET <christophe.jaillet@xxxxxxxxxx> wrote:

> Use 'devm_iio_kfifo_allocate()' instead of 'iio_kfifo_allocate()' in order
> to simplify code and avoid a memory leak in an error path in
> 'sca3000_probe()'. A call to 'sca3000_unconfigure_ring()' was missing.
>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Applied to the togreg branch of iio.git and pushed out as testing
for the autobuilders to play with it.

I thought about queueing this up as a fix, but as it is unlikely
to be hit and there is another patch (which isn't a fix) dependent
on it I went with the worst of both worlds and took it for the next
merge window whilst marking it for stable.

I added a note to the description to say why for when people see
it next cycle

Thanks,

Jonathan

> ---
> v2: Use a devm_ function to fix the leak reported in v1.
> This makes 'sca3000_unconfigure_ring()' useless and simplify code.
> ---
> drivers/iio/accel/sca3000.c | 9 +--------
> 1 file changed, 1 insertion(+), 8 deletions(-)
>
> diff --git a/drivers/iio/accel/sca3000.c b/drivers/iio/accel/sca3000.c
> index f33dadf7b262..562f125235db 100644
> --- a/drivers/iio/accel/sca3000.c
> +++ b/drivers/iio/accel/sca3000.c
> @@ -1277,7 +1277,7 @@ static int sca3000_configure_ring(struct iio_dev *indio_dev)
> {
> struct iio_buffer *buffer;
>
> - buffer = iio_kfifo_allocate();
> + buffer = devm_iio_kfifo_allocate(&indio_dev->dev);
> if (!buffer)
> return -ENOMEM;
>
> @@ -1287,11 +1287,6 @@ static int sca3000_configure_ring(struct iio_dev *indio_dev)
> return 0;
> }
>
> -static void sca3000_unconfigure_ring(struct iio_dev *indio_dev)
> -{
> - iio_kfifo_free(indio_dev->buffer);
> -}
> -
> static inline
> int __sca3000_hw_ring_state_set(struct iio_dev *indio_dev, bool state)
> {
> @@ -1546,8 +1541,6 @@ static int sca3000_remove(struct spi_device *spi)
> if (spi->irq)
> free_irq(spi->irq, indio_dev);
>
> - sca3000_unconfigure_ring(indio_dev);
> -
> return 0;
> }
>