Add a non-NULL check to fix potential NULL pointer dereference
Cleanup code to call function once.
Signed-off-by: Aaron Ma <aaron...@canonical.com>
---
drivers/iommu/amd_iommu.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 2a7b78bb98b4..dbda5b86f979 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -140,9 +140,14 @@ static inline int match_hid_uid(struct device *dev,
struct acpihid_map_entry *entry)
{
const char *hid, *uid;
+ struct acpi_device *adev = ACPI_COMPANION(dev);
- hid = acpi_device_hid(ACPI_COMPANION(dev));
- uid = acpi_device_uid(ACPI_COMPANION(dev));
+ if (!adev) {
+ return -ENODEV;
+ }
+
+ hid = acpi_device_hid(adev);
+ uid = acpi_device_uid(adev);
if (!hid || !(*hid))
return -ENODEV;
--
2.20.1
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
