This is a note to let you know that I've just added the patch titled
cpufreq: CPPC: Fix possible null-ptr-deref for cppc_get_cpu_cost()
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
cpufreq-cppc-fix-possible-null-ptr-deref-for-cppc_ge.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9cee8fb4b6628a7865b9c8569f5885ba5fdaa1db
Author: Jinjie Ruan <ruanjinjie@xxxxxxxxxx>
Date: Wed Oct 30 16:24:49 2024 +0800
cpufreq: CPPC: Fix possible null-ptr-deref for cppc_get_cpu_cost()
[ Upstream commit 1a1374bb8c5926674973d849feed500bc61ad535 ]
cpufreq_cpu_get_raw() may return NULL if the cpu is not in
policy->cpus cpu mask and it will cause null pointer dereference,
so check NULL for cppc_get_cpu_cost().
Fixes: 740fcdc2c20e ("cpufreq: CPPC: Register EM based on efficiency class information")
Signed-off-by: Jinjie Ruan <ruanjinjie@xxxxxxxxxx>
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index 284c328a1d3d1..866a0538ca896 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -498,6 +498,9 @@ static int cppc_get_cpu_cost(struct device *cpu_dev, unsigned long KHz,
int step;
policy = cpufreq_cpu_get_raw(cpu_dev->id);
+ if (!policy)
+ return 0;
+
cpu_data = policy->driver_data;
perf_caps = &cpu_data->perf_caps;
max_cap = arch_scale_cpu_capacity(cpu_dev->id);
