Hi Javier,
On Fri, Aug 31, 2018 at 05:19:06PM +0200, Javier Martinez Canillas wrote:
> The driver registers the subdev async in the middle of the probe function
> but this has to be done at the very end of the probe function to prevent
> registering a device whose probe function could fail (i.e: the clock and
> regulators enable can fail, the I2C transfers could return errors, etc).
>
> It could also lead to a media device driver that is waiting to bound the
> v4l2 subdevice to incorrectly expose its media device to userspace, since
> the subdev is registered but later its media entity is cleaned up on error.
>
> Fixes: 3ee47cad3e69 ("media: ov2680: Add Omnivision OV2680 sensor driver")
> Signed-off-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
>
> ---
>
> drivers/media/i2c/ov2680.c | 9 ++++-----
> 1 file changed, 4 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/media/i2c/ov2680.c b/drivers/media/i2c/ov2680.c
> index f753a1c333ef..2ef920a17278 100644
> --- a/drivers/media/i2c/ov2680.c
> +++ b/drivers/media/i2c/ov2680.c
> @@ -983,10 +983,6 @@ static int ov2680_v4l2_init(struct ov2680_dev *sensor)
>
> sensor->sd.ctrl_handler = hdl;
>
> - ret = v4l2_async_register_subdev(&sensor->sd);
> - if (ret < 0)
> - goto cleanup_entity;
> -
> return 0;
>
> cleanup_entity:
> @@ -1096,6 +1092,10 @@ static int ov2680_probe(struct i2c_client *client)
> if (ret < 0)
> goto error_cleanup;
How about instead moving ov2680_check_id() call earlier in probe()? That
would seem to be a better fix: the driver should check the device is around
before registering anything.
>
> + ret = v4l2_async_register_subdev(&sensor->sd);
> + if (ret < 0)
> + goto error_cleanup;
> +
> dev_info(dev, "ov2680 init correctly\n");
>
> return 0;
> @@ -1104,7 +1104,6 @@ static int ov2680_probe(struct i2c_client *client)
> dev_err(dev, "ov2680 init fail: %d\n", ret);
>
> media_entity_cleanup(&sensor->sd.entity);
> - v4l2_async_unregister_subdev(&sensor->sd);
> v4l2_ctrl_handler_free(&sensor->ctrls.handler);
>
> lock_destroy:
--
Regards,
Sakari Ailus
e-mail: sakari.ailus@xxxxxx
