Messages in this thread Patch in this message | | | From | Viacheslav Mitrofanov <> | Subject | [PATCH 1/1] perf: RISC-V: Limit the number of counters returned from SBI. | Date | Fri, 28 Apr 2023 11:02:56 +0000 |
| |
Perf gets the number of supported counters from SBI. If it happens that the number of returned counters more than RISCV_MAX_COUNTERS the code trusts it. It does not lead to an immediate problem but can potentially lead to it. Prevent getting more than RISCV_MAX_COUNTERS from SBI.
Signed-off-by: Viacheslav Mitrofanov <v.v.mitrofanov@yadro.com> --- drivers/perf/riscv_pmu_sbi.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c index 70cb50fd41c2..0183bf911bfb 100644 --- a/drivers/perf/riscv_pmu_sbi.c +++ b/drivers/perf/riscv_pmu_sbi.c @@ -867,6 +867,11 @@ static int pmu_sbi_device_probe(struct platform_device *pdev) pr_err("SBI PMU extension doesn't provide any counters\n"); goto out_free; } + /* It is possible to get from SBI more than max number of counters */ + if (num_counters > RISCV_MAX_COUNTERS) { + pr_warn("SBI returned more than maximum number of counters\n"); + num_counters = RISCV_MAX_COUNTERS; + } /* cache all the information about counters now */ if (pmu_sbi_get_ctrinfo(num_counters, &cmask)) -- 2.37.2
| |