[PATCH] iommu/amd: Fix PCI device reference leak in iommu_call_iopf_notifier()

[Wentao Liang]

pci_get_domain_bus_and_slot() returns a PCI device with an elevated
reference count, but iommu_call_iopf_notifier() never drops it, neither
when the page request has been reported nor on the abort path.

Put the device reference on both exits.

Fixes: 978d626b8f1a ("iommu/amd: Add IO page fault notifier handler")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Wentao Liang <vulab@xxxxxxxxxxx>
---
 drivers/iommu/amd/ppr.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iommu/amd/ppr.c b/drivers/iommu/amd/ppr.c
index 1f8d2823bea4..1e4392b17bd8 100644
--- a/drivers/iommu/amd/ppr.c
+++ b/drivers/iommu/amd/ppr.c
@@ -151,6 +151,7 @@ static void iommu_call_iopf_notifier(struct amd_iommu *iommu, u64 *raw)
 
 	/* Submit event */
 	iommu_report_device_fault(&pdev->dev, &event);
+	pci_dev_put(pdev);
 
 	return;
 
@@ -159,6 +160,7 @@ static void iommu_call_iopf_notifier(struct amd_iommu *iommu, u64 *raw)
 	amd_iommu_complete_ppr(&pdev->dev, PPR_PASID(raw[0]),
 			       IOMMU_PAGE_RESP_FAILURE,
 			       PPR_TAG(raw[0]) & 0x1FF);
+	pci_dev_put(pdev);
 }
 
 void amd_iommu_poll_ppr_log(struct amd_iommu *iommu)
-- 
2.34.1