From 3564cddefb5bd0de65510cd17da2253808eef6e7 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Mon, 1 Jun 2020 15:39:47 +0200 Subject: [PATCH] leds: lm3533: fix use-after-free on unbind commit d584221e683bbd173738603b83a315f27d27d043 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: 50154e29e5cc ("leds: lm3533: 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-lm3533.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/leds/leds-lm3533.c b/drivers/leds/leds-lm3533.c index 9504ad405aef..b3edee703193 100644 --- a/drivers/leds/leds-lm3533.c +++ b/drivers/leds/leds-lm3533.c @@ -694,7 +694,7 @@ static int lm3533_led_probe(struct platform_device *pdev) platform_set_drvdata(pdev, led); - ret = devm_led_classdev_register(pdev->dev.parent, &led->cdev); + ret = led_classdev_register(pdev->dev.parent, &led->cdev); if (ret) { dev_err(&pdev->dev, "failed to register LED %d\n", pdev->id); return ret; @@ -704,13 +704,18 @@ static int lm3533_led_probe(struct platform_device *pdev) ret = lm3533_led_setup(led, pdata); if (ret) - return ret; + goto err_deregister; ret = lm3533_ctrlbank_enable(&led->cb); if (ret) - return ret; + goto err_deregister; return 0; + +err_deregister: + led_classdev_unregister(&led->cdev); + + return ret; } static int lm3533_led_remove(struct platform_device *pdev) @@ -720,6 +725,7 @@ static int lm3533_led_remove(struct platform_device *pdev) dev_dbg(&pdev->dev, "%s\n", __func__); lm3533_ctrlbank_disable(&led->cb); + led_classdev_unregister(&led->cdev); return 0; }