[PATCH] DMA mapping leak in error path in __nvme_fc_init_requet()

[wenxiong at linux.ibm.com]

From: Wen Xiong <wenxiong at linux.ibm.com>

In __nvme_fc_init_request(), if the first DMA mapping for cmddma succeeds
but the second DMA mapping for rspdma fails, the function returns an error
without unmapping the first successful DMA mapping. This causes a DMA
resource leak.

Fix this by unmapping cmddma before returning the error when rspdma
mapping fails.

Signed-off-by: Wen Xiong <wenxiong at linux.ibm.com>
---
 drivers/nvme/host/fc.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
index 68a5d971657b..7684fb053963 100644
--- a/drivers/nvme/host/fc.c
+++ b/drivers/nvme/host/fc.c
@@ -2129,6 +2129,8 @@ __nvme_fc_init_request(struct nvme_fc_ctrl *ctrl,
 	if (fc_dma_mapping_error(ctrl->lport->dev, op->fcp_req.rspdma)) {
 		dev_err(ctrl->dev,
 			"FCP Op failed - rspiu dma mapping failed.\n");
+		fc_dma_unmap_single(ctrl->lport->dev, op->fcp_req.cmddma,
+				sizeof(op->cmd_iu), DMA_TO_DEVICE);
 		ret = -EFAULT;
 	}
 
-- 
2.52.0