Hi Andi,
On Sat, Sep 30, 2017 at 05:38:28AM +0900, Andi Shyti wrote:
> Commit 57b8ff070f98 ("driver core: add devm_device_add_group()
> and friends") has added the the managed version for creating
> sysfs group files.
>
> Use devm_device_add_group instead of sysfs_create_group and
> remove the relative sysfs_remove_group and goto label.
>
> CC: Michael Hennerich <michael.henner...@analog.com>
> Signed-off-by: Andi Shyti <a...@etezian.org>
> ---
> drivers/input/touchscreen/ad7877.c | 8 ++------
> 1 file changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/input/touchscreen/ad7877.c
> b/drivers/input/touchscreen/ad7877.c
> index 9c250ae780d9..677ba38b4d1c 100644
> --- a/drivers/input/touchscreen/ad7877.c
> +++ b/drivers/input/touchscreen/ad7877.c
> @@ -783,18 +783,16 @@ static int ad7877_probe(struct spi_device *spi)
> goto err_free_mem;
> }
>
> - err = sysfs_create_group(&spi->dev.kobj, &ad7877_attr_group);
> + err = devm_device_add_group(&spi->dev, &ad7877_attr_group);
This changes order of operations and ultimately may cause use-after-free
as memory for ad7877 structure will be freed before we remove
attributes.
> if (err)
> goto err_free_irq;
>
> err = input_register_device(input_dev);
> if (err)
> - goto err_remove_attr_group;
> + goto err_free_irq;
>
> return 0;
>
> -err_remove_attr_group:
> - sysfs_remove_group(&spi->dev.kobj, &ad7877_attr_group);
> err_free_irq:
> free_irq(spi->irq, ts);
> err_free_mem:
> @@ -807,8 +805,6 @@ static int ad7877_remove(struct spi_device *spi)
> {
> struct ad7877 *ts = spi_get_drvdata(spi);
>
> - sysfs_remove_group(&spi->dev.kobj, &ad7877_attr_group);
> -
> ad7877_disable(ts);
> free_irq(ts->spi->irq, ts);
>
> --
> 2.14.2
>
Thanks.
--
Dmitry
