Several MFD child drivers register their class devices directly under the parent device. This means you cannot blindly do devres conversions so that deregistration ends up being tied to the parent device, something which leads to use-after-free on driver unbind when the class device is released while still being registered.
Fixes: 8d3b6a4001ce ("leds: wm831x-status: Use devm_led_classdev_register") Cc: stable stable@vger.kernel.org # 4.6 Cc: Amitoj Kaur Chawla amitoj1606@gmail.com Signed-off-by: Johan Hovold johan@kernel.org --- drivers/leds/leds-wm831x-status.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/drivers/leds/leds-wm831x-status.c b/drivers/leds/leds-wm831x-status.c index 082df7f1dd90..67f4235cb28a 100644 --- a/drivers/leds/leds-wm831x-status.c +++ b/drivers/leds/leds-wm831x-status.c @@ -269,12 +269,23 @@ static int wm831x_status_probe(struct platform_device *pdev) drvdata->cdev.blink_set = wm831x_status_blink_set; drvdata->cdev.groups = wm831x_status_groups;
- ret = devm_led_classdev_register(wm831x->dev, &drvdata->cdev); + ret = led_classdev_register(wm831x->dev, &drvdata->cdev); if (ret < 0) { dev_err(&pdev->dev, "Failed to register LED: %d\n", ret); return ret; }
+ platform_set_drvdata(pdev, drvdata); + + return 0; +} + +static int wm831x_status_remove(struct platform_device *pdev) +{ + struct wm831x_status *drvdata = platform_get_drvdata(pdev); + + led_classdev_unregister(&drvdata->cdev); + return 0; }
@@ -283,6 +294,7 @@ static struct platform_driver wm831x_status_driver = { .name = "wm831x-status", }, .probe = wm831x_status_probe, + .remove = wm831x_status_remove, };
module_platform_driver(wm831x_status_driver);