| Message ID | 20221230075159.1482626-1-linmq006@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | powercap/dtpm_cpu: Fix refcount leak in __dtpm_cpu_setup | expand |
On Fri, Dec 30, 2022 at 8:52 AM Miaoqian Lin <linmq006@gmail.com> wrote: > > The policy return by cpufreq_cpu_get() should be released with > cpufreq_cpu_put() to balance the reference counter. > Add missing cpufreq_cpu_put() to fix this. > > Fixes: 0e8f68d7f048 ("powercap/drivers/dtpm: Add CPU energy model based support") > Signed-off-by: Miaoqian Lin <linmq006@gmail.com> > --- > drivers/powercap/dtpm_cpu.c | 17 ++++++++++++----- > 1 file changed, 12 insertions(+), 5 deletions(-) > > diff --git a/drivers/powercap/dtpm_cpu.c b/drivers/powercap/dtpm_cpu.c > index 2ff7717530bf..3083c6b45c90 100644 > --- a/drivers/powercap/dtpm_cpu.c > +++ b/drivers/powercap/dtpm_cpu.c > @@ -195,12 +195,16 @@ static int __dtpm_cpu_setup(int cpu, struct dtpm *parent) > return 0; > > pd = em_cpu_get(cpu); > - if (!pd || em_is_artificial(pd)) > - return -EINVAL; > + if (!pd || em_is_artificial(pd)) { > + ret = -EINVAL; > + goto out_put_policy; > + } > > dtpm_cpu = kzalloc(sizeof(*dtpm_cpu), GFP_KERNEL); > - if (!dtpm_cpu) > - return -ENOMEM; > + if (!dtpm_cpu) { > + ret = -ENOMEM; > + goto out_put_policy; > + } > > dtpm_init(&dtpm_cpu->dtpm, &dtpm_ops); > dtpm_cpu->cpu = cpu; > @@ -220,6 +224,8 @@ static int __dtpm_cpu_setup(int cpu, struct dtpm *parent) > if (ret) > goto out_dtpm_unregister; The part of the patch above is valid, but I don't think that the policy reference counter can be dropped below, because that may allow the policy to go away and this driver will be still using it, won't it? > > + cpufreq_cpu_put(policy); > + > return 0; > > out_dtpm_unregister: > @@ -230,7 +236,8 @@ static int __dtpm_cpu_setup(int cpu, struct dtpm *parent) > for_each_cpu(cpu, policy->related_cpus) > per_cpu(dtpm_per_cpu, cpu) = NULL; > kfree(dtpm_cpu); > - > +out_put_policy: > + cpufreq_cpu_put(policy); > return ret; > } > > -- > 2.25.1 >
diff --git a/drivers/powercap/dtpm_cpu.c b/drivers/powercap/dtpm_cpu.c index 2ff7717530bf..3083c6b45c90 100644 --- a/drivers/powercap/dtpm_cpu.c +++ b/drivers/powercap/dtpm_cpu.c @@ -195,12 +195,16 @@ static int __dtpm_cpu_setup(int cpu, struct dtpm *parent) return 0; pd = em_cpu_get(cpu); - if (!pd || em_is_artificial(pd)) - return -EINVAL; + if (!pd || em_is_artificial(pd)) { + ret = -EINVAL; + goto out_put_policy; + } dtpm_cpu = kzalloc(sizeof(*dtpm_cpu), GFP_KERNEL); - if (!dtpm_cpu) - return -ENOMEM; + if (!dtpm_cpu) { + ret = -ENOMEM; + goto out_put_policy; + } dtpm_init(&dtpm_cpu->dtpm, &dtpm_ops); dtpm_cpu->cpu = cpu; @@ -220,6 +224,8 @@ static int __dtpm_cpu_setup(int cpu, struct dtpm *parent) if (ret) goto out_dtpm_unregister; + cpufreq_cpu_put(policy); + return 0; out_dtpm_unregister: @@ -230,7 +236,8 @@ static int __dtpm_cpu_setup(int cpu, struct dtpm *parent) for_each_cpu(cpu, policy->related_cpus) per_cpu(dtpm_per_cpu, cpu) = NULL; kfree(dtpm_cpu); - +out_put_policy: + cpufreq_cpu_put(policy); return ret; }
The policy return by cpufreq_cpu_get() should be released with cpufreq_cpu_put() to balance the reference counter. Add missing cpufreq_cpu_put() to fix this. Fixes: 0e8f68d7f048 ("powercap/drivers/dtpm: Add CPU energy model based support") Signed-off-by: Miaoqian Lin <linmq006@gmail.com> --- drivers/powercap/dtpm_cpu.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-)