Re: [kvm-unit-tests patch v6 07/18] x86: pmu: Fix potential out of bound access for fixed events

Mi, Dapeng
2025-02-18T09:34:15Z

On 2/15/2025 5:07 AM, Sean Christopherson wrote:
> On Sat, Sep 14, 2024, Dapeng Mi wrote:
>> @@ -744,6 +753,12 @@ int main(int ac, char **av)
>> printf("Fixed counters: %d\n", pmu.nr_fixed_counters);
>> printf("Fixed counter width: %d\n", pmu.fixed_counter_width);
>>
>> + fixed_counters_num = MIN(pmu.nr_fixed_counters, ARRAY_SIZE(fixed_events));
>> + if (pmu.nr_fixed_counters > ARRAY_SIZE(fixed_events))
>> + report_info("Fixed counters number %d > defined fixed events %ld. "
> Doesn't compile on 32-bit builds. Easiest thing is to cast ARRAY_SIZE, because
> size_t is different between 32-bit and 64-bit.

But ARRAY_SIZE() should return same value regardless of 32-bit or 64-bit,
right?

>
>> + "Please update test case.", pmu.nr_fixed_counters,
>> + ARRAY_SIZE(fixed_events));
>> +
>> apic_write(APIC_LVTPC, PMI_VECTOR);
>>
>> check_counters();
>> --
>> 2.40.1
>>