[PATCH 5.10/5.15] cpufreq: davinci: Fix clk use after free

[PATCH 5.10/5.15] cpufreq: davinci: Fix clk use after free

[Vasiliy Kovalev]

From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

[ 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>
(cherry picked from commit a5f024d0e6f91e05c816ad4ee8837173369dd5cb)
[ kovalev: bp to fix CVE-2023-53544 ]
Signed-off-by: Vasiliy Kovalev <kovalev@altlinux.org>
---
 drivers/cpufreq/davinci-cpufreq.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/davinci-cpufreq.c b/drivers/cpufreq/davinci-cpufreq.c
index 91f477a6cbc4..62380f05aec8 100644
--- a/drivers/cpufreq/davinci-cpufreq.c
+++ b/drivers/cpufreq/davinci-cpufreq.c
@@ -133,12 +133,14 @@ 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 = {
-- 
2.50.1