Re: [PATCH] cpufreq: CPPC: Fix possible null-ptr-deref for cppc_get_cpu_cost()
From: Viresh Kumar
Date: Wed Oct 30 2024 - 05:09:12 EST
On 30-10-24, 16:24, Jinjie Ruan wrote:
> 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>
> ---
> drivers/cpufreq/cppc_cpufreq.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
> index 2b8708475ac7..67fa97bbeae7 100644
> --- a/drivers/cpufreq/cppc_cpufreq.c
> +++ b/drivers/cpufreq/cppc_cpufreq.c
> @@ -487,6 +487,9 @@ 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);
Applied. Thanks.
--
viresh