[PATCH v4 11/14] nvmet-fcloop: drop response if targetport is gone

[Daniel Wagner <wagi@kernel.org>]

When the target port is gone, the lsrsp pointer is invalid. Thus don't
call the done function anymore instead just drop the response.

This happens when the target sends a disconnect association. After this
the target starts tearing down all resources and doesn't expect any
response.

Signed-off-by: Daniel Wagner <wagi@kernel.org>
---
 drivers/nvme/target/fcloop.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/nvme/target/fcloop.c b/drivers/nvme/target/fcloop.c
index ca11230bffedb0f2313a99e24e54e892daf0d644..bb45721ec0f028399d810cbd7891bc6975801752 100644
--- a/drivers/nvme/target/fcloop.c
+++ b/drivers/nvme/target/fcloop.c
@@ -493,16 +493,25 @@ fcloop_t2h_xmt_ls_rsp(struct nvme_fc_local_port *localport,
 	struct nvmet_fc_target_port *targetport = rport->targetport;
 	struct fcloop_tport *tport;
 
-	memcpy(lsreq->rspaddr, lsrsp->rspbuf,
-		((lsreq->rsplen < lsrsp->rsplen) ?
-				lsreq->rsplen : lsrsp->rsplen));
-	lsrsp->done(lsrsp);
-
 	if (!targetport) {
+		/*
+		 * The target port is gone. The target doesn't expect any
+		 * response anymore and the ->done call is not valid
+		 * because the resources have been freed by
+		 * nvmet_fc_free_pending_reqs.
+		 *
+		 * We end up here from delete association exchange:
+		 * nvmet_fc_xmt_disconnect_assoc sends an async request.
+		 */
 		kmem_cache_free(lsreq_cache, tls_req);
 		return 0;
 	}
 
+	memcpy(lsreq->rspaddr, lsrsp->rspbuf,
+		((lsreq->rsplen < lsrsp->rsplen) ?
+				lsreq->rsplen : lsrsp->rsplen));
+	lsrsp->done(lsrsp);
+
 	tport = targetport->private;
 	spin_lock(&tport->lock);
 	list_add_tail(&tls_req->ls_list, &tport->ls_list);

-- 
2.49.0