cpufreq: davinci: Fix clk use after free

[ Upstream commit 5d8f384a9b4fc50f6a18405f1c08e5a87a77b5b3 ]

The remove function first frees the clks and only then calls
cpufreq_unregister_driver(). If one of the cpufreq callbacks is called
just before cpufreq_unregister_driver() is run, the freed clks might be
used.

Fixes: 6601b8030de3 ("davinci: add generic CPUFreq driver for DaVinci")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/cpufreq/davinci-cpufreq.c b/drivers/cpufreq/davinci-cpufreq.c
index d54a27c9912188f472705ade364574e63a90780e..3dacfc53a80da5640c094f368f365e6ba757702b 100644 (file)
--- a/drivers/cpufreq/davinci-cpufreq.c
+++ b/drivers/cpufreq/davinci-cpufreq.c
@@ -138,12 +138,14 @@ static int __init davinci_cpufreq_probe(struct platform_device *pdev)
 
 static int __exit davinci_cpufreq_remove(struct platform_device *pdev)
 {
+       cpufreq_unregister_driver(&davinci_driver);
+
        clk_put(cpufreq.armclk);
 
        if (cpufreq.asyncclk)
                clk_put(cpufreq.asyncclk);
 
-       return cpufreq_unregister_driver(&davinci_driver);
+       return 0;
 }
 
 static struct platform_driver davinci_cpufreq_driver = {