From: Henry Martin <bsdhenrymartin@gmail.com>
Date: Tue, 8 Apr 2025 15:03:54 +0000 (+0800)
Subject: cpufreq: scpi: Fix null-ptr-deref in scpi_cpufreq_get_rate()
X-Git-Tag: v6.15-rc4~20^2^2~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=73b24dc731731edf762f9454552cb3a5b7224949;p=thirdparty%2Fkernel%2Flinux.git

cpufreq: scpi: Fix null-ptr-deref in scpi_cpufreq_get_rate()

cpufreq_cpu_get_raw() can return NULL when the target CPU is not present
in the policy->cpus mask. scpi_cpufreq_get_rate() does not check for
this case, which results in a NULL pointer dereference.

Fixes: 343a8d17fa8d ("cpufreq: scpi: remove arm_big_little dependency")
Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---

diff --git a/drivers/cpufreq/scpi-cpufreq.c b/drivers/cpufreq/scpi-cpufreq.c
index 17cda84f00dfb..dcbb0ae7dd476 100644
--- a/drivers/cpufreq/scpi-cpufreq.c
+++ b/drivers/cpufreq/scpi-cpufreq.c
@@ -29,9 +29,16 @@ static struct scpi_ops *scpi_ops;
 
 static unsigned int scpi_cpufreq_get_rate(unsigned int cpu)
 {
-	struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu);
-	struct scpi_data *priv = policy->driver_data;
-	unsigned long rate = clk_get_rate(priv->clk);
+	struct cpufreq_policy *policy;
+	struct scpi_data *priv;
+	unsigned long rate;
+
+	policy = cpufreq_cpu_get_raw(cpu);
+	if (unlikely(!policy))
+		return 0;
+
+	priv = policy->driver_data;
+	rate = clk_get_rate(priv->clk);
 
 	return rate / 1000;
 }