From: Schspa Shi schspa@gmail.com
mainline inclusion from mainline-v5.19-rc1 commit d4627a287e251efed59f2b4bda82c5950768c963 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8EI9L?from=project-issue CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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If policy initialization fails after the sysfs files are created, there is a possibility to end up running show()/store() callbacks for half-initialized policies, which may have unpredictable outcomes.
Abort show()/store() in such a case by making sure the policy is active.
Also dectivate the policy on such failures.
Signed-off-by: Schspa Shi schspa@gmail.com Acked-by: Viresh Kumar viresh.kumar@linaro.org [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com
Conflicts: drivers/cpufreq/cpufreq.c
Signed-off-by: Jinjie Ruan ruanjinjie@huawei.com --- drivers/cpufreq/cpufreq.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 58342390966b..9897d842c8a4 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -946,13 +946,14 @@ static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) { struct cpufreq_policy *policy = to_policy(kobj); struct freq_attr *fattr = to_attr(attr); - ssize_t ret; + ssize_t ret = -EBUSY;
if (!fattr->show) return -EIO;
down_read(&policy->rwsem); - ret = fattr->show(policy, buf); + if (likely(!policy_is_inactive(policy))) + ret = fattr->show(policy, buf); up_read(&policy->rwsem);
return ret; @@ -963,7 +964,7 @@ static ssize_t store(struct kobject *kobj, struct attribute *attr, { struct cpufreq_policy *policy = to_policy(kobj); struct freq_attr *fattr = to_attr(attr); - ssize_t ret = -EINVAL; + ssize_t ret = -EBUSY;
if (!fattr->store) return -EIO; @@ -977,7 +978,8 @@ static ssize_t store(struct kobject *kobj, struct attribute *attr,
if (cpu_online(policy->cpu)) { down_write(&policy->rwsem); - ret = fattr->store(policy, buf, count); + if (likely(!policy_is_inactive(policy))) + ret = fattr->store(policy, buf, count); up_write(&policy->rwsem); }
@@ -1515,6 +1517,7 @@ static int cpufreq_online(unsigned int cpu) for_each_cpu(j, policy->real_cpus) remove_cpu_dev_symlink(policy, get_cpu_device(j));
+ cpumask_clear(policy->cpus); up_write(&policy->rwsem);
out_offline_policy: