ACPI / processor_thermal: avoid null pointer deference error
Fix a null pointer deference by acpi_driver_data() if device is
null. We should only set pr and check this is OK after we are
sure device is not null.
Smatch analysis:
drivers/acpi/processor_thermal.c:223 processor_get_max_state() warn:
variable dereferenced before check 'device' (see line 221)
drivers/acpi/processor_thermal.c:237 processor_get_cur_state() warn:
variable dereferenced before check 'device' (see line 235)
drivers/acpi/processor_thermal.c:255 processor_set_cur_state() warn:
variable dereferenced before check 'device' (see line 251)
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/processor_thermal.c b/drivers/acpi/processor_thermal.c
index 641b545..e8e6527 100644
--- a/drivers/acpi/processor_thermal.c
+++ b/drivers/acpi/processor_thermal.c
@@ -218,9 +218,13 @@
unsigned long *state)
{
struct acpi_device *device = cdev->devdata;
- struct acpi_processor *pr = acpi_driver_data(device);
+ struct acpi_processor *pr;
- if (!device || !pr)
+ if (!device)
+ return -EINVAL;
+
+ pr = acpi_driver_data(device);
+ if (!pr)
return -EINVAL;
*state = acpi_processor_max_state(pr);
@@ -232,9 +236,13 @@
unsigned long *cur_state)
{
struct acpi_device *device = cdev->devdata;
- struct acpi_processor *pr = acpi_driver_data(device);
+ struct acpi_processor *pr;
- if (!device || !pr)
+ if (!device)
+ return -EINVAL;
+
+ pr = acpi_driver_data(device);
+ if (!pr)
return -EINVAL;
*cur_state = cpufreq_get_cur_state(pr->id);
@@ -248,11 +256,15 @@
unsigned long state)
{
struct acpi_device *device = cdev->devdata;
- struct acpi_processor *pr = acpi_driver_data(device);
+ struct acpi_processor *pr;
int result = 0;
int max_pstate;
- if (!device || !pr)
+ if (!device)
+ return -EINVAL;
+
+ pr = acpi_driver_data(device);
+ if (!pr)
return -EINVAL;
max_pstate = cpufreq_get_max_state(pr->id);