x86/cpufreq: check array index before use

... rather than after.

Signed-off-by: Jan Beulich <jbeulich@novell.com>

diff --git a/xen/arch/x86/acpi/cpufreq/cpufreq.c b/xen/arch/x86/acpi/cpufreq/cpufreq.c
index a9b1d239a227f08a58729cc5ac065741e066e3ab..d9697ddf3229d2367e4eeec3a6d9926f1fe02e7d 100644 (file)
--- a/xen/arch/x86/acpi/cpufreq/cpufreq.c
+++ b/xen/arch/x86/acpi/cpufreq/cpufreq.c
@@ -210,9 +210,11 @@ static u32 get_cur_val(cpumask_t mask)
 
     if (!cpu_isset(cpu, mask))
         cpu = first_cpu(mask);
-    policy = cpufreq_cpu_policy[cpu];
+    if (cpu >= NR_CPUS)
+        return 0;
 
-    if (cpu >= NR_CPUS || !policy || !drv_data[policy->cpu])
+    policy = cpufreq_cpu_policy[cpu];
+    if (!policy || !drv_data[policy->cpu])
         return 0;    
 
     switch (drv_data[policy->cpu]->cpu_feature) {