[PATCH v5 01/18] xen/pmstat: guard perf.states[] access with XEN_PX_INIT

[Penny Zheng <Penny.Zheng@xxxxxxx>]

Accessing to perf.states[] array shall not be only guarded with user-defined
hypercall input, so we add XEN_PX_INIT check to gain safety.

Signed-off-by: Penny Zheng <Penny.Zheng@xxxxxxx>
---
v4 -> v5:
- new commit
---
 xen/drivers/acpi/pmstat.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/xen/drivers/acpi/pmstat.c b/xen/drivers/acpi/pmstat.c
index c51b9ca358..b7fcc02db9 100644
--- a/xen/drivers/acpi/pmstat.c
+++ b/xen/drivers/acpi/pmstat.c
@@ -228,10 +228,13 @@ static int get_cpufreq_para(struct xen_sysctl_pm_op *op)
     ret = copy_to_guest(op->u.get_para.affected_cpus,
                         data, op->u.get_para.cpu_num);
 
-    for ( i = 0; i < op->u.get_para.freq_num; i++ )
-        data[i] = pmpt->perf.states[i].core_frequency * 1000;
-    ret += copy_to_guest(op->u.get_para.scaling_available_frequencies,
-                         data, op->u.get_para.freq_num);
+    if ( pmpt->perf.init & XEN_PX_INIT )
+    {
+        for ( i = 0; i < op->u.get_para.freq_num; i++ )
+            data[i] = pmpt->perf.states[i].core_frequency * 1000;
+        ret += copy_to_guest(op->u.get_para.scaling_available_frequencies,
+                             data, op->u.get_para.freq_num);
+    }
 
     xfree(data);
     if ( ret )
-- 
2.34.1