6.6-stable review patch. If anyone has any objections, please let me know.
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From: Junhao He hejunhao3@huawei.com
[ Upstream commit 81bdd60a3d1d3b05e6cc6674845afb1694dd3a0e ]
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 hejunhao3@huawei.com Signed-off-by: Hao Chen chenhao418@huawei.com Acked-by: Jonathan Cameron Jonathan.Cameron@huawei.com Reviewed-by: Jijie Shao shaojijie@huawei.com Link: https://lore.kernel.org/r/20240425124627.13764-3-hejunhao3@huawei.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 16869bf5bf4cc..cbdd53b0a0342 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)