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authorAaron Ma <aaron.ma@canonical.com>2019-03-13 21:53:24 +0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-12-05 09:21:18 +0100
commitaa1844c9137e7fae79b94ad87017167320419dee (patch)
treeaa45b87dbb4d3791f8a3391cb7e0ccc73ca2fecc
parent320ab115caf10ce500fbdd9ae9b2d322dc80d744 (diff)
iommu/amd: Fix NULL dereference bug in match_hid_uid
[ Upstream commit bb6bccba390c7d743c1e4427de4ef284c8cc6869 ] Add a non-NULL check to fix potential NULL pointer dereference Cleanup code to call function once. Signed-off-by: Aaron Ma <aaron.ma@canonical.com> Fixes: 2bf9a0a12749b ('iommu/amd: Add iommu support for ACPI HID devices') Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r--drivers/iommu/amd_iommu.c8
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 1f2ed44de243..fe18804a5008 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -139,10 +139,14 @@ 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;