From 99aa36386351488d12ad5d302e096a77f22705d9 Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Mon, 25 Mar 2013 10:50:06 +0000 Subject: 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 Signed-off-by: Rafael J. Wysocki 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 @@ processor_get_max_state(struct thermal_cooling_device *cdev, 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 @@ processor_get_cur_state(struct thermal_cooling_device *cdev, 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 @@ processor_set_cur_state(struct thermal_cooling_device *cdev, 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); -- cgit v0.10.2