[PATCH net 2/4] mlxsw: spectrum_switchdev: Avoid leaking FID's reference count

[Ido Schimmel]

It should never be possible for a user to set a VNI on a FID in case one
is already set. The driver therefore returns an error, but fails to drop
the reference count taken earlier when calling
mlxsw_sp_fid_8021d_lookup().

Drop the reference when this unlikely error is hit.

Fixes: 1c30d1836aeb ("mlxsw: spectrum: Enable VxLAN enslavement to bridges")
Signed-off-by: Ido Schimmel <ido...@mellanox.com>
Reviewed-by: Jiri Pirko <j...@mellanox.com>
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c 
b/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c
index 739a51f0a366..7f2091c2648e 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c
@@ -2134,8 +2134,10 @@ mlxsw_sp_bridge_8021d_vxlan_join(struct 
mlxsw_sp_bridge_device *bridge_device,
        if (!fid)
                return -EINVAL;
 
-       if (mlxsw_sp_fid_vni_is_set(fid))
-               return -EINVAL;
+       if (mlxsw_sp_fid_vni_is_set(fid)) {
+               err = -EINVAL;
+               goto err_vni_exists;
+       }
 
        err = mlxsw_sp_nve_fid_enable(mlxsw_sp, fid, &params, extack);
        if (err)
@@ -2149,6 +2151,7 @@ mlxsw_sp_bridge_8021d_vxlan_join(struct 
mlxsw_sp_bridge_device *bridge_device,
        return 0;
 
 err_nve_fid_enable:
+err_vni_exists:
        mlxsw_sp_fid_put(fid);
        return err;
 }
-- 
2.19.1