[PATCH 1/1] iommu: Fix potential memory leak in iopf_queue_remove_device()

[Lu Baolu]

The iopf_queue_remove_device() helper removes a device from the per-iommu
iopf queue when PRI is disabled on the device. It responds to all
outstanding iopf's with an IOMMU_PAGE_RESP_INVALID code and detaches the
device from the queue.

However, it fails to release the group structure that represents a group
of iopf's awaiting for a response after responding to the hardware. This
can cause a memory leak if iopf_queue_remove_device() is called with
pending iopf's.

Fix it by calling iopf_free_group() after the iopf group is responded.

Fixes: 199112327135 ("iommu: Track iopf group instead of last fault")
Cc: stable@xxxxxxxxxxxxxxx
Suggested-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
 drivers/iommu/io-pgfault.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/iommu/io-pgfault.c b/drivers/iommu/io-pgfault.c
index 4674e618797c..8b5926c1452e 100644
--- a/drivers/iommu/io-pgfault.c
+++ b/drivers/iommu/io-pgfault.c
@@ -478,6 +478,7 @@ void iopf_queue_remove_device(struct iopf_queue *queue, struct device *dev)
 
 		ops->page_response(dev, iopf, &resp);
 		list_del_init(&group->pending_node);
+		iopf_free_group(group);
 	}
 	mutex_unlock(&fault_param->lock);
 
-- 
2.43.0