2022-05-27 07:11:15

by Miaoqian Lin

[permalink] [raw]
Subject: [PATCH] devfreq: exynos-ppmu: Fix refcount leak in of_get_devfreq_events

of_get_child_by_name() returns a node pointer with refcount
incremented, we should use of_node_put() on it when done.
This function only calls of_node_put() in normal path,
missing it in error paths.
Add missing of_node_put() to avoid refcount leak.

Fixes: f262f28c1470 ("PM / devfreq: event: Add devfreq_event class")
Signed-off-by: Miaoqian Lin <[email protected]>
---
drivers/devfreq/event/exynos-ppmu.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/devfreq/event/exynos-ppmu.c b/drivers/devfreq/event/exynos-ppmu.c
index 9b849d781116..a443e7c42daf 100644
--- a/drivers/devfreq/event/exynos-ppmu.c
+++ b/drivers/devfreq/event/exynos-ppmu.c
@@ -519,15 +519,19 @@ static int of_get_devfreq_events(struct device_node *np,

count = of_get_child_count(events_np);
desc = devm_kcalloc(dev, count, sizeof(*desc), GFP_KERNEL);
- if (!desc)
+ if (!desc) {
+ of_node_put(events_np);
return -ENOMEM;
+ }
info->num_events = count;

of_id = of_match_device(exynos_ppmu_id_match, dev);
if (of_id)
info->ppmu_type = (enum exynos_ppmu_type)of_id->data;
- else
+ else {
+ of_node_put(events_np);
return -EINVAL;
+ }

j = 0;
for_each_child_of_node(events_np, node) {
--
2.25.1



2022-06-18 14:14:18

by Chanwoo Choi

[permalink] [raw]
Subject: Re: [PATCH] devfreq: exynos-ppmu: Fix refcount leak in of_get_devfreq_events

On 22. 5. 26. 17:28, Miaoqian Lin wrote:
> of_get_child_by_name() returns a node pointer with refcount
> incremented, we should use of_node_put() on it when done.
> This function only calls of_node_put() in normal path,
> missing it in error paths.
> Add missing of_node_put() to avoid refcount leak.
>
> Fixes: f262f28c1470 ("PM / devfreq: event: Add devfreq_event class")
> Signed-off-by: Miaoqian Lin <[email protected]>
> ---
> drivers/devfreq/event/exynos-ppmu.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/devfreq/event/exynos-ppmu.c b/drivers/devfreq/event/exynos-ppmu.c
> index 9b849d781116..a443e7c42daf 100644
> --- a/drivers/devfreq/event/exynos-ppmu.c
> +++ b/drivers/devfreq/event/exynos-ppmu.c
> @@ -519,15 +519,19 @@ static int of_get_devfreq_events(struct device_node *np,
>
> count = of_get_child_count(events_np);
> desc = devm_kcalloc(dev, count, sizeof(*desc), GFP_KERNEL);
> - if (!desc)
> + if (!desc) {
> + of_node_put(events_np);
> return -ENOMEM;
> + }
> info->num_events = count;
>
> of_id = of_match_device(exynos_ppmu_id_match, dev);
> if (of_id)
> info->ppmu_type = (enum exynos_ppmu_type)of_id->data;
> - else
> + else {
> + of_node_put(events_np);
> return -EINVAL;
> + }
>
> j = 0;
> for_each_child_of_node(events_np, node) {


Applied it. Thanks.

--
Best Regards,
Samsung Electronics
Chanwoo Choi

2022-06-18 14:21:10

by Chanwoo Choi

[permalink] [raw]
Subject: Re: [PATCH] devfreq: exynos-ppmu: Fix refcount leak in of_get_devfreq_events

On 22. 5. 26. 17:28, Miaoqian Lin wrote:
> of_get_child_by_name() returns a node pointer with refcount
> incremented, we should use of_node_put() on it when done.
> This function only calls of_node_put() in normal path,
> missing it in error paths.
> Add missing of_node_put() to avoid refcount leak.
>
> Fixes: f262f28c1470 ("PM / devfreq: event: Add devfreq_event class")
> Signed-off-by: Miaoqian Lin <[email protected]>
> ---
> drivers/devfreq/event/exynos-ppmu.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/devfreq/event/exynos-ppmu.c b/drivers/devfreq/event/exynos-ppmu.c
> index 9b849d781116..a443e7c42daf 100644
> --- a/drivers/devfreq/event/exynos-ppmu.c
> +++ b/drivers/devfreq/event/exynos-ppmu.c
> @@ -519,15 +519,19 @@ static int of_get_devfreq_events(struct device_node *np,
>
> count = of_get_child_count(events_np);
> desc = devm_kcalloc(dev, count, sizeof(*desc), GFP_KERNEL);
> - if (!desc)
> + if (!desc) {
> + of_node_put(events_np);
> return -ENOMEM;
> + }
> info->num_events = count;
>
> of_id = of_match_device(exynos_ppmu_id_match, dev);
> if (of_id)
> info->ppmu_type = (enum exynos_ppmu_type)of_id->data;
> - else
> + else {
> + of_node_put(events_np);
> return -EINVAL;
> + }
>
> j = 0;
> for_each_child_of_node(events_np, node) {

I edited the patch title with 'PM / ' prefix
in order to keep the consistent style of title as following:

PM / devfreq: exynos-ppmu: Fix refcount leak in of_get_devfreq_events


--
Best Regards,
Samsung Electronics
Chanwoo Choi