RDMA/cm: Fix memory leak in ib_cm_insert_listen

cm_alloc_id_priv() allocates resource for the cm_id_priv. When
cm_init_listen() fails it doesn't free it, leading to memory leak.

Add the missing error unwind.

Fixes: 98f67156 ("RDMA/cm: Simplify establishing a listen cm_id")
Link: https://lore.kernel.org/r/20220621052546.4821-1-linmq006@gmail.comSigned-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/core/cm.c

@@ -1252,8 +1252,10 @@ struct ib_cm_id *ib_cm_insert_listen(struct ib_device *device,
 		return ERR_CAST(cm_id_priv);
 
 	err = cm_init_listen(cm_id_priv, service_id, 0);
-	if (err)
+	if (err) {
+		ib_destroy_cm_id(&cm_id_priv->id);
 		return ERR_PTR(err);
+	}
 
 	spin_lock_irq(&cm_id_priv->lock);
 	listen_id_priv = cm_insert_listen(cm_id_priv, cm_handler);