examples/power: fix buffer overrun

[ upstream commit 3f1fc5f ]

The freqs array in freq_info struct has RTE_MAX_LCORE_FREQS elements,
yet the code can attempt to look at the index at  RTE_MAX_LCORE,
which may be greater than RTE_MAX_LCORE_FREQS. Fix to limit index to
RTE_MAX_LCORE_FREQS.

Coverity issue: 337660
Fixes: d26c18c ("examples/vm_power: cpu frequency in host")

Signed-off-by: David Hunt <david.hunt@intel.com>
Acked-by: Reshma Pattan <reshma.pattan@intel.com>

examples/vm_power_manager/power_manager.c

@@ -157,7 +157,7 @@ power_manager_get_current_frequency(unsigned core_num)
 	rte_spinlock_lock(&global_core_freq_info[core_num].power_sl);
 	index = rte_power_get_freq(core_num);
 	rte_spinlock_unlock(&global_core_freq_info[core_num].power_sl);
-	if (index >= POWER_MGR_MAX_CPUS)
+	if (index >= RTE_MAX_LCORE_FREQS)
 		freq = 0;
 	else
 		freq = global_core_freq_info[core_num].freqs[index];