From: Johan Hovold johan@kernel.org
commit 6f4aa35744f69ed9b0bf5a736c9ca9b44bc1dcea upstream.
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: eed16255d66b ("leds: da903x: 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 Signed-off-by: Pavel Machek pavel@ucw.cz Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/leds/leds-da903x.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-)
--- a/drivers/leds/leds-da903x.c +++ b/drivers/leds/leds-da903x.c @@ -113,12 +113,23 @@ static int da903x_led_probe(struct platf led->flags = pdata->flags; led->master = pdev->dev.parent;
- ret = devm_led_classdev_register(led->master, &led->cdev); + ret = led_classdev_register(led->master, &led->cdev); if (ret) { dev_err(&pdev->dev, "failed to register LED %d\n", id); return ret; }
+ platform_set_drvdata(pdev, led); + + return 0; +} + +static int da903x_led_remove(struct platform_device *pdev) +{ + struct da903x_led *led = platform_get_drvdata(pdev); + + led_classdev_unregister(&led->cdev); + return 0; }
@@ -127,6 +138,7 @@ static struct platform_driver da903x_led .name = "da903x-led", }, .probe = da903x_led_probe, + .remove = da903x_led_remove, };
module_platform_driver(da903x_led_driver);