From: Yongqiang Liu <liuyongqiang13@xxxxxxxxxx>
commit 5c51054896bcce1d33d39fead2af73fec24f40b6 upstream.
In cpufreq_policy_alloc(), it will call uninitialed completion in
cpufreq_sysfs_release() when kobject_init_and_add() fails. And
that will cause a crash such as the following page fault in complete:
BUG: unable to handle page fault for address: fffffffffffffff8
[..]
RIP: 0010:complete+0x98/0x1f0
[..]
Call Trace:
kobject_put+0x1be/0x4c0
cpufreq_online.cold+0xee/0x1fd
cpufreq_add_dev+0x183/0x1e0
subsys_interface_register+0x3f5/0x4e0
cpufreq_register_driver+0x3b7/0x670
acpi_cpufreq_init+0x56c/0x1000 [acpi_cpufreq]
do_one_initcall+0x13d/0x780
do_init_module+0x1c3/0x630
load_module+0x6e67/0x73b0
__do_sys_finit_module+0x181/0x240
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Fixes: 4ebe36c94aed ("cpufreq: Fix kobject memleak")
Signed-off-by: Yongqiang Liu <liuyongqiang13@xxxxxxxxxx>
Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Cc: 5.2+ <stable@xxxxxxxxxxxxxxx> # 5.2+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/cpufreq/cpufreq.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1204,6 +1204,7 @@ static struct cpufreq_policy *cpufreq_po
if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL))
goto err_free_rcpumask;
+ init_completion(&policy->kobj_unregister);
ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq,
cpufreq_global_kobject, "policy%u", cpu);
if (ret) {
@@ -1242,7 +1243,6 @@ static struct cpufreq_policy *cpufreq_po
init_rwsem(&policy->rwsem);
spin_lock_init(&policy->transition_lock);
init_waitqueue_head(&policy->transition_wait);
- init_completion(&policy->kobj_unregister);
INIT_WORK(&policy->update, handle_update);
policy->cpu = cpu;
