2024-04-25 12:49:09

by Junhao He

Subject: [PATCH 2/3] drivers/perf: hisi: hns3: Fix out-of-bound access when valid event group

The perf tool allows users to create event groups through following
cmd [1], but the driver does not check whether the array index is out
of bounds when writing data to the event_group array. If the number of
events in an event_group is greater than HNS3_PMU_MAX_HW_EVENTS, the
memory write overflow of event_group array occurs.

Add array index check to fix the possible array out of bounds violation,
and return directly when write new events are written to array bounds.

There are 9 different events in an event_group.
[1] perf stat -e '{pmu/event1/, ... ,pmu/event9/}

Fixes: 66637ab137b4 ("drivers/perf: hisi: add driver for HNS3 PMU")
Signed-off-by: Junhao He <[email protected]>
Signed-off-by: Hao Chen <[email protected]>
---
drivers/perf/hisilicon/hns3_pmu.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/perf/hisilicon/hns3_pmu.c b/drivers/perf/hisilicon/hns3_pmu.c
index 16869bf5bf4c..cbdd53b0a034 100644
--- a/drivers/perf/hisilicon/hns3_pmu.c
+++ b/drivers/perf/hisilicon/hns3_pmu.c
@@ -1085,15 +1085,27 @@ static bool hns3_pmu_validate_event_group(struct perf_event *event)
return false;

for (num = 0; num < counters; num++) {
+ /*
+ * If we find a related event, then it's a valid group
+ * since we don't need to allocate a new counter for it.
+ */
if (hns3_pmu_cmp_event(event_group[num], sibling))
break;
}

+ /*
+ * Otherwise it's a new event but if there's no available counter,
+ * fail the check since we cannot schedule all the events in
+ * the group simultaneously.
+ */
+ if (num == HNS3_PMU_MAX_HW_EVENTS)
+ return false;
+
if (num == counters)
event_group[counters++] = sibling;
}

- return counters <= HNS3_PMU_MAX_HW_EVENTS;
+ return true;
}

static u32 hns3_pmu_get_filter_condition(struct perf_event *event)
--
2.33.0

2024-04-26 10:20:21

by Jijie Shao

Subject: Re: [PATCH 2/3] drivers/perf: hisi: hns3: Fix out-of-bound access when valid event group

Reviewed-by: Jijie Shao<[email protected]>

on 2024/4/25 20:46, Junhao He wrote:
> The perf tool allows users to create event groups through following
> cmd [1], but the driver does not check whether the array index is out
> of bounds when writing data to the event_group array. If the number of
> events in an event_group is greater than HNS3_PMU_MAX_HW_EVENTS, the
> memory write overflow of event_group array occurs.
>
> Add array index check to fix the possible array out of bounds violation,
> and return directly when write new events are written to array bounds.
>
> There are 9 different events in an event_group.
> [1] perf stat -e '{pmu/event1/, ... ,pmu/event9/}
>
> Fixes: 66637ab137b4 ("drivers/perf: hisi: add driver for HNS3 PMU")
> Signed-off-by: Junhao He <[email protected]>
> Signed-off-by: Hao Chen <[email protected]>
> ---
> drivers/perf/hisilicon/hns3_pmu.c | 14 +++++++++++++-
> 1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/perf/hisilicon/hns3_pmu.c b/drivers/perf/hisilicon/hns3_pmu.c
> index 16869bf5bf4c..cbdd53b0a034 100644
> --- a/drivers/perf/hisilicon/hns3_pmu.c
> +++ b/drivers/perf/hisilicon/hns3_pmu.c
> @@ -1085,15 +1085,27 @@ static bool hns3_pmu_validate_event_group(struct perf_event *event)
> return false;
>
> for (num = 0; num < counters; num++) {
> + /*
> + * If we find a related event, then it's a valid group
> + * since we don't need to allocate a new counter for it.
> + */
> if (hns3_pmu_cmp_event(event_group[num], sibling))
> break;
> }
>
> + /*
> + * Otherwise it's a new event but if there's no available counter,
> + * fail the check since we cannot schedule all the events in
> + * the group simultaneously.
> + */
> + if (num == HNS3_PMU_MAX_HW_EVENTS)
> + return false;
> +
> if (num == counters)
> event_group[counters++] = sibling;
> }
>
> - return counters <= HNS3_PMU_MAX_HW_EVENTS;
> + return true;
> }
>
> static u32 hns3_pmu_get_filter_condition(struct perf_event *event)

2024-04-26 16:07:20

by Jonathan Cameron

Subject: Re: [PATCH 2/3] drivers/perf: hisi: hns3: Fix out-of-bound access when valid event group

On Thu, 25 Apr 2024 20:46:26 +0800
Junhao He <[email protected]> wrote:

> The perf tool allows users to create event groups through following
> cmd [1], but the driver does not check whether the array index is out
> of bounds when writing data to the event_group array. If the number of
> events in an event_group is greater than HNS3_PMU_MAX_HW_EVENTS, the
> memory write overflow of event_group array occurs.
>
> Add array index check to fix the possible array out of bounds violation,
> and return directly when write new events are written to array bounds.
>
> There are 9 different events in an event_group.
> [1] perf stat -e '{pmu/event1/, ... ,pmu/event9/}
>
> Fixes: 66637ab137b4 ("drivers/perf: hisi: add driver for HNS3 PMU")
> Signed-off-by: Junhao He <[email protected]>
> Signed-off-by: Hao Chen <[email protected]>

Acked-by: Jonathan Cameron <[email protected]>

> ---
> drivers/perf/hisilicon/hns3_pmu.c | 14 +++++++++++++-
> 1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/perf/hisilicon/hns3_pmu.c b/drivers/perf/hisilicon/hns3_pmu.c
> index 16869bf5bf4c..cbdd53b0a034 100644
> --- a/drivers/perf/hisilicon/hns3_pmu.c
> +++ b/drivers/perf/hisilicon/hns3_pmu.c
> @@ -1085,15 +1085,27 @@ static bool hns3_pmu_validate_event_group(struct perf_event *event)
> return false;
>
> for (num = 0; num < counters; num++) {
> + /*
> + * If we find a related event, then it's a valid group
> + * since we don't need to allocate a new counter for it.
> + */
> if (hns3_pmu_cmp_event(event_group[num], sibling))
> break;
> }
>
> + /*
> + * Otherwise it's a new event but if there's no available counter,
> + * fail the check since we cannot schedule all the events in
> + * the group simultaneously.
> + */
> + if (num == HNS3_PMU_MAX_HW_EVENTS)
> + return false;
> +
> if (num == counters)
> event_group[counters++] = sibling;
> }
>
> - return counters <= HNS3_PMU_MAX_HW_EVENTS;
> + return true;
> }
>
> static u32 hns3_pmu_get_filter_condition(struct perf_event *event)