[PATCH] intel_menlow: avoid null pointer deference error

From: Young Xiao
Date: Tue May 28 2019 - 21:58:21 EST


Fix a null pointer deference by acpi_driver_data() if device is
null (dereference before check). We should only set cdev and check
this is OK after we are sure device is not null.

Signed-off-by: Young Xiao <92siuyang@xxxxxxxxx>
---
drivers/platform/x86/intel_menlow.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/x86/intel_menlow.c b/drivers/platform/x86/intel_menlow.c
index 77eb870..28feb5c 100644
--- a/drivers/platform/x86/intel_menlow.c
+++ b/drivers/platform/x86/intel_menlow.c
@@ -180,9 +180,13 @@ static int intel_menlow_memory_add(struct acpi_device *device)

static int intel_menlow_memory_remove(struct acpi_device *device)
{
- struct thermal_cooling_device *cdev = acpi_driver_data(device);
+ struct thermal_cooling_device *cdev;
+
+ if (!device)
+ return -EINVAL;

- if (!device || !cdev)
+ cdev = acpi_driver_data(device);
+ if (!cdev)
return -EINVAL;

sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
--
2.7.4