From 385c1ae9ddb936033cf76a9ed62d8e3e5a5a85e6 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Mon, 1 Jun 2020 15:39:46 +0200 Subject: [PATCH] leds: da903x: fix use-after-free on unbind 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 # 4.6 Cc: Amitoj Kaur Chawla Signed-off-by: Johan Hovold Signed-off-by: Pavel Machek Signed-off-by: Greg Kroah-Hartman --- drivers/leds/leds-da903x.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/leds/leds-da903x.c b/drivers/leds/leds-da903x.c index ed1b303f699f..2b5fb00438a2 100644 --- a/drivers/leds/leds-da903x.c +++ b/drivers/leds/leds-da903x.c @@ -110,12 +110,23 @@ static int da903x_led_probe(struct platform_device *pdev) 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; } @@ -124,6 +135,7 @@ static struct platform_driver da903x_led_driver = { .name = "da903x-led", }, .probe = da903x_led_probe, + .remove = da903x_led_remove, }; module_platform_driver(da903x_led_driver);