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

[Mi, Dapeng]

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
>>