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From:   Brian Norris <briannorris@chromium.org>
To:     MyungJoo Ham <myungjoo.ham@samsung.com>,
        Kyungmin Park <kyungmin.park@samsung.com>,
        Chanwoo Choi <cw00.choi@samsung.com>,
        Rob Herring <robh+dt@kernel.org>
Cc:     Lin Huang <hl@rock-chips.com>, Heiko Stuebner <heiko@sntech.de>,
        Derek Basehore <dbasehore@chromium.org>,
        linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-pm@vger.kernel.org, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        Brian Norris <briannorris@chromium.org>
Subject: [PATCH v3 15/15] PM / devfreq: rk3399_dmc: Avoid static (reused) profile
Date:   Mon,  7 Mar 2022 16:09:45 -0800
Message-Id: <20220307160918.v3.15.I8d71e9555aca1fa7e532d22dd1ef27976f21799d@changeid>
In-Reply-To: <20220308000945.706701-1-briannorris@chromium.org>
References: <20220308000945.706701-1-briannorris@chromium.org>
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Precedence: bulk

This static struct can get reused if the device gets removed/reprobed,
and that causes use-after-free in its ->freq_table.

Let's just move the struct to our dynamic allocation.

Signed-off-by: Brian Norris <briannorris@chromium.org>
---

(no changes since v2)

Changes in v2:
 * New patch

 drivers/devfreq/rk3399_dmc.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/devfreq/rk3399_dmc.c b/drivers/devfreq/rk3399_dmc.c
index 9615658d04ae..e494d1497d60 100644
--- a/drivers/devfreq/rk3399_dmc.c
+++ b/drivers/devfreq/rk3399_dmc.c
@@ -38,6 +38,7 @@
 struct rk3399_dmcfreq {
 	struct device *dev;
 	struct devfreq *devfreq;
+	struct devfreq_dev_profile profile;
 	struct devfreq_simple_ondemand_data ondemand_data;
 	struct clk *dmc_clk;
 	struct devfreq_event_dev *edev;
@@ -228,13 +229,6 @@ static int rk3399_dmcfreq_get_cur_freq(struct device *dev, unsigned long *freq)
 	return 0;
 }
 
-static struct devfreq_dev_profile rk3399_devfreq_dmc_profile = {
-	.polling_ms	= 200,
-	.target		= rk3399_dmcfreq_target,
-	.get_dev_status	= rk3399_dmcfreq_get_dev_status,
-	.get_cur_freq	= rk3399_dmcfreq_get_cur_freq,
-};
-
 static __maybe_unused int rk3399_dmcfreq_suspend(struct device *dev)
 {
 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
@@ -422,10 +416,16 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
 	data->volt = dev_pm_opp_get_voltage(opp);
 	dev_pm_opp_put(opp);
 
-	rk3399_devfreq_dmc_profile.initial_freq = data->rate;
+	data->profile = (struct devfreq_dev_profile) {
+		.polling_ms	= 200,
+		.target		= rk3399_dmcfreq_target,
+		.get_dev_status	= rk3399_dmcfreq_get_dev_status,
+		.get_cur_freq	= rk3399_dmcfreq_get_cur_freq,
+		.initial_freq	= data->rate,
+	};
 
 	data->devfreq = devm_devfreq_add_device(dev,
-					   &rk3399_devfreq_dmc_profile,
+					   &data->profile,
 					   DEVFREQ_GOV_SIMPLE_ONDEMAND,
 					   &data->ondemand_data);
 	if (IS_ERR(data->devfreq)) {
-- 
2.35.1.616.g0bdcbb4464-goog