From: Keir Fraser <keir.fraser@citrix.com>
Date: Fri, 5 Dec 2008 15:22:21 +0000 (+0000)
Subject: powernow: implement struct cpufreq_driver.verify
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~14026^2~64
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=a886bbd1ef6360a71bbb65b6b7d67bc992e09c6e;p=xen.git

powernow: implement struct cpufreq_driver.verify

Without this, under rare conditions hypervisor crashes are possible
due to this method being called without checking against NULL.

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

diff --git a/xen/arch/x86/acpi/cpufreq/powernow.c b/xen/arch/x86/acpi/cpufreq/powernow.c
index b43de6a5cf..f69b425a0c 100644
--- a/xen/arch/x86/acpi/cpufreq/powernow.c
+++ b/xen/arch/x86/acpi/cpufreq/powernow.c
@@ -129,6 +129,16 @@ static int powernow_cpufreq_target(struct cpufreq_policy *policy,
     return result;
 }
 
+static int powernow_cpufreq_verify(struct cpufreq_policy *policy)
+{
+    struct powernow_cpufreq_data *data;
+
+    if (!policy || !(data = drv_data[policy->cpu]))
+        return -EINVAL;
+
+    return cpufreq_frequency_table_verify(policy, data->freq_table);
+}
+
 static int powernow_cpufreq_cpu_init(struct cpufreq_policy *policy)
 {
     unsigned int i;
@@ -243,6 +253,7 @@ static int powernow_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 }
 
 static struct cpufreq_driver powernow_cpufreq_driver = {
+    .verify = powernow_cpufreq_verify,
     .target = powernow_cpufreq_target,
     .init   = powernow_cpufreq_cpu_init,
     .exit   = powernow_cpufreq_cpu_exit