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

Sean Christopherson
2025-02-14T21:07:40Z

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.

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