From: Junhao He <hejunhao3@huawei.com> Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- 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 HISI_PCIE_MAX_COUNTERS, 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: 8404b0fbc7fb ("drivers/perf: hisi: Add driver for HiSilicon PCIe PMU") Signed-off-by: Junhao He <hejunhao3@huawei.com> Reviewed-by: Jijie Shao <shaojijie@huawei.com> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/20240425124627.13764-2-hejunhao3@huawei.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Luo Gengkun <luogengkun2@huawei.com> --- drivers/perf/hisilicon/hisi_pcie_pmu.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/perf/hisilicon/hisi_pcie_pmu.c b/drivers/perf/hisilicon/hisi_pcie_pmu.c index 26a63e7539c0..4018bdca0a36 100644 --- a/drivers/perf/hisilicon/hisi_pcie_pmu.c +++ b/drivers/perf/hisilicon/hisi_pcie_pmu.c @@ -356,15 +356,27 @@ static bool hisi_pcie_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 (hisi_pcie_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 == HISI_PCIE_MAX_COUNTERS) + return false; + if (num == counters) event_group[counters++] = sibling; } - return counters <= HISI_PCIE_MAX_COUNTERS; + return true; } static int hisi_pcie_pmu_event_init(struct perf_event *event) -- 2.34.1