Merge tag 'iommu-fix-v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU fix from Joerg Roedel:
"Fix a NULL-pointer dereference issue in the ACPI device matching code
of the AMD IOMMU driver"
* tag 'iommu-fix-v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/amd: Fix NULL dereference bug in match_hid_uid
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 6b0760d..b319e51 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -140,10 +140,14 @@ static struct lock_class_key reserved_rbtree_key;
static inline int match_hid_uid(struct device *dev,
struct acpihid_map_entry *entry)
{
+ struct acpi_device *adev = ACPI_COMPANION(dev);
const char *hid, *uid;
- 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;
