Commit b39c0615 authored Aug 20, 2020 by Hauke Mehrtens Committed by Thierry Reding Sep 24, 2020

pwm: img: Fix null pointer access in probe



dev_get_drvdata() is called in img_pwm_runtime_resume() before the
driver data is set.
When pm_runtime_enabled() returns false in img_pwm_probe() it calls
img_pwm_runtime_resume() which results in a null pointer access.

This patch fixes the problem by setting the driver data earlier in the
img_pwm_probe() function.

This crash was seen when booting the Imagination Technologies Creator
Ci40 (Marduk) with kernel 5.4 in OpenWrt.

Fixes: e690ae52 ("pwm: img: Add runtime PM")
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

parent bce54366

drivers/pwm/pwm-img.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -277,6 +277,8 @@ static int img_pwm_probe(struct platform_device *pdev)
		return PTR_ERR(pwm->pwm_clk);
		}

		platform_set_drvdata(pdev, pwm);

		pm_runtime_set_autosuspend_delay(&pdev->dev, IMG_PWM_PM_TIMEOUT);
		pm_runtime_use_autosuspend(&pdev->dev);
		pm_runtime_enable(&pdev->dev);
		@@ -313,7 +315,6 @@ static int img_pwm_probe(struct platform_device *pdev)
		goto err_suspend;
		}

		platform_set_drvdata(pdev, pwm);
		return 0;

		err_suspend:

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