IB/core: Save QP in ib_flow structure

When we create flow steering rule, we need to save the related QP in the
ib_flow struct. this QP is used in destroy flow.

Move the QP assignment from ib_uverbs_ex_create_flow into ib_create_flow,
this would allow both kernel and userspace consumers to use it.

This bug wasn't seen in the wild because there are no kernel consumers
currently in the kernel.

Fixes: 319a441d ("IB/core: Add receive flow steering support")
Signed-off-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/core/uverbs_cmd.c

@@ -3745,7 +3745,6 @@ int ib_uverbs_ex_create_flow(struct ib_uverbs_file *file,
 		err = PTR_ERR(flow_id);
 		goto err_free;
 	}
-	flow_id->qp = qp;
 	flow_id->uobject = uobj;
 	uobj->object = flow_id;
 

drivers/infiniband/core/verbs.c

@@ -1734,8 +1734,10 @@ struct ib_flow *ib_create_flow(struct ib_qp *qp,
 		return ERR_PTR(-ENOSYS);
 
 	flow_id = qp->device->create_flow(qp, flow_attr, domain);
-	if (!IS_ERR(flow_id))
+	if (!IS_ERR(flow_id)) {
 		atomic_inc(&qp->usecnt);
+		flow_id->qp = qp;
+	}
 	return flow_id;
 }
 EXPORT_SYMBOL(ib_create_flow);