net/mlx5: E-switch, Return correct error code on group creation failure

Dan Carpenter report:
The patch f47e04eb96e0: "net/mlx5: E-switch, Allow setting share/max
tx rate limits of rate groups" from May 31, 2021, leads to the
following Smatch static checker warning:

	drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c:483 esw_qos_create_rate_group()
	warn: passing zero to 'ERR_PTR'

If min rate normalization failed then error code may be overwritten to 0
if scheduling element destruction succeed. Ignore this value and always
return initial one.

Fixes: f47e04eb96e0 ("net/mlx5: E-switch, Allow setting share/max tx rate limits of rate groups")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c b/drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c
index 985e305..c6cc67c 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c
@@ -473,10 +473,9 @@ esw_qos_create_rate_group(struct mlx5_eswitch *esw, struct netlink_ext_ack *exta
 
 err_min_rate:
        list_del(&group->list);
-       err = mlx5_destroy_scheduling_element_cmd(esw->dev,
-                                                 SCHEDULING_HIERARCHY_E_SWITCH,
-                                                 group->tsar_ix);
-       if (err)
+       if (mlx5_destroy_scheduling_element_cmd(esw->dev,
+                                               SCHEDULING_HIERARCHY_E_SWITCH,
+                                               group->tsar_ix))
                NL_SET_ERR_MSG_MOD(extack, "E-Switch destroy TSAR for group failed");
 err_sched_elem:
        kfree(group);