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Diffstat (limited to 'drivers/cpufreq/cpufreq.c')
-rw-r--r--drivers/cpufreq/cpufreq.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index dd1628192310..0a10cf9d0b1a 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -933,6 +933,9 @@ static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
struct freq_attr *fattr = to_attr(attr);
ssize_t ret;
+ if (!fattr->show)
+ return -EIO;
+
down_read(&policy->rwsem);
ret = fattr->show(policy, buf);
up_read(&policy->rwsem);
@@ -947,6 +950,9 @@ static ssize_t store(struct kobject *kobj, struct attribute *attr,
struct freq_attr *fattr = to_attr(attr);
ssize_t ret = -EINVAL;
+ if (!fattr->store)
+ return -EIO;
+
/*
* cpus_read_trylock() is used here to work around a circular lock
* dependency problem with respect to the cpufreq_register_driver().