From: Aleksandr Mishin <amishin@t-argos.ru> stable inclusion from stable-v6.6.33 commit f84b9b25d045e67a7eee5e73f21278c8ab06713c category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IA74DQ Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit cf7de25878a1f4508c69dc9f6819c21ba177dbfe ] cppc_cpufreq_get_rate() and hisi_cppc_cpufreq_get_rate() can be called from different places with various parameters. So cpufreq_cpu_get() can return null as 'policy' in some circumstances. Fix this bug by adding null return check. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: a28b2bfc099c ("cppc_cpufreq: replace per-cpu data array with a list") Signed-off-by: Aleksandr Mishin <amishin@t-argos.ru> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Conflicts: drivers/cpufreq/cppc_cpufreq.c [Context conflict] Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Signed-off-by: Liu Mingrui <liumingrui@huawei.com> --- drivers/cpufreq/cppc_cpufreq.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c index 321a9dc9484d..0d60699ad63e 100644 --- a/drivers/cpufreq/cppc_cpufreq.c +++ b/drivers/cpufreq/cppc_cpufreq.c @@ -865,10 +865,15 @@ static unsigned int cppc_cpufreq_get_rate(unsigned int cpu) { struct fb_ctr_pair fb_ctrs = { .cpu = cpu, }; struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); - struct cppc_cpudata *cpu_data = policy->driver_data; + struct cppc_cpudata *cpu_data; u64 delivered_perf; int ret; + if (!policy) + return -ENODEV; + + cpu_data = policy->driver_data; + cpufreq_cpu_put(policy); if (cpu_has_amu_feat(cpu)) @@ -948,10 +953,15 @@ static struct cpufreq_driver cppc_cpufreq_driver = { static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu) { struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); - struct cppc_cpudata *cpu_data = policy->driver_data; + struct cppc_cpudata *cpu_data; u64 desired_perf; int ret; + if (!policy) + return -ENODEV; + + cpu_data = policy->driver_data; + cpufreq_cpu_put(policy); ret = cppc_get_desired_perf(cpu, &desired_perf); -- 2.25.1