lkml.org 
[lkml]   [2021]   [Jun]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH V3 1/4] cpufreq: cppc: Fix potential memleak in cppc_cpufreq_cpu_init
Hi,

On Monday 21 Jun 2021 at 14:49:34 (+0530), Viresh Kumar wrote:
> It's a classic example of memleak, we allocate something, we fail and
> never free the resources.
>
> Make sure we free all resources on policy ->init() failures.
>
> Fixes: a28b2bfc099c ("cppc_cpufreq: replace per-cpu data array with a list")

This is on me, thanks for the fix!

Might be better for this to be separate from the series, but I suppose
all will be going in 5.14 anyway.

> Tested-by: Vincent Guittot <vincent.guittot@linaro.org>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
> drivers/cpufreq/cppc_cpufreq.c | 30 ++++++++++++++++++++----------
> 1 file changed, 20 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
> index be4f62e2c5f1..35b8ae66d1fb 100644
> --- a/drivers/cpufreq/cppc_cpufreq.c
> +++ b/drivers/cpufreq/cppc_cpufreq.c
> @@ -256,6 +256,16 @@ static struct cppc_cpudata *cppc_cpufreq_get_cpu_data(unsigned int cpu)
> return NULL;
> }
>
> +static void cppc_cpufreq_put_cpu_data(struct cpufreq_policy *policy)
> +{
> + struct cppc_cpudata *cpu_data = policy->driver_data;
> +
> + list_del(&cpu_data->node);
> + free_cpumask_var(cpu_data->shared_cpu_map);
> + kfree(cpu_data);
> + policy->driver_data = NULL;
> +}
> +
> static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
> {
> unsigned int cpu = policy->cpu;
> @@ -309,7 +319,8 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
> default:
> pr_debug("Unsupported CPU co-ord type: %d\n",
> policy->shared_type);
> - return -EFAULT;
> + ret = -EFAULT;
> + goto out;
> }
>
> /*
> @@ -324,10 +335,14 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
> cpu_data->perf_ctrls.desired_perf = caps->highest_perf;
>
> ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
> - if (ret)
> - pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",
> - caps->highest_perf, cpu, ret);
> + if (!ret)
> + return 0;
>
> + pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",
> + caps->highest_perf, cpu, ret);
> +

Nit: I would have preferred the more traditional:

if (ret) {
pr_debug();
goto out;
}

return 0;

It's always easier to read.

Thanks,
Ionela.

> +out:
> + cppc_cpufreq_put_cpu_data(policy);
> return ret;
> }
>
> @@ -345,12 +360,7 @@ static int cppc_cpufreq_cpu_exit(struct cpufreq_policy *policy)
> pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n",
> caps->lowest_perf, cpu, ret);
>
> - /* Remove CPU node from list and free driver data for policy */
> - free_cpumask_var(cpu_data->shared_cpu_map);
> - list_del(&cpu_data->node);
> - kfree(policy->driver_data);
> - policy->driver_data = NULL;
> -
> + cppc_cpufreq_put_cpu_data(policy);
> return 0;
> }
>
> --
> 2.31.1.272.g89b43f80a514
>

\
 
 \ /
  Last update: 2021-06-23 15:45    [W:0.270 / U:0.292 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site