From: Sagi Grimberg <sagi@grimberg.me>
Date: Sun, 14 Jan 2018 18:34:22 +0200
Subject: nvmet: release a ns reference in nvmet_req_uninit if needed
Patch-mainline: v4.16-rc1
Git-commit: 423b4487fb23cc9bcbf14f748915bff46151506a
References: FATE#323952, FATE#322506

nvmet_req_init looked up a namespace and took a reference on it (unless it
failed prior to that). If the request is uninitialized (in error cases) we
need to remove that reference in case it was taken, otherwise we leak
namespace reference when calling nvme_req_uninit.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
---
 drivers/nvme/target/core.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -512,6 +512,7 @@ bool nvmet_req_init(struct nvmet_req *re
 	req->sg_cnt = 0;
 	req->transfer_len = 0;
 	req->rsp->status = 0;
+	req->ns = NULL;
 
 	/* no support for fused commands yet */
 	if (unlikely(flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND))) {
@@ -557,6 +558,8 @@ EXPORT_SYMBOL_GPL(nvmet_req_init);
 void nvmet_req_uninit(struct nvmet_req *req)
 {
 	percpu_ref_put(&req->sq->ref);
+	if (req->ns)
+		nvmet_put_namespace(req->ns);
 }
 EXPORT_SYMBOL_GPL(nvmet_req_uninit);