net/mlx5: Fix multiple updates of steering rules in parallel

mainline inclusion
from mainline-5.1-rc1
commit 6237634d
category: bugfix
bugzilla: 12601
CVE: NA

-------------------------------------------------

There might be a condition where the fte found is not active yet. In
this case we should not use it, but continue to search for another, or
allocate a new one.

Fixes: bd71b08e ("net/mlx5: Support multiple updates of steering rules in parallel")
Signed-off-by: NEli Britstein <elibr@mellanox.com>
Reviewed-by: NMaor Gottlieb <maorg@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>
Signed-off-by: NZhiqiang Liu <liuzhiqiang26@huawei.com>
Reviewed-by: NWenan Mao <maowenan@huawei.com>
Reviewed-by: NWenan Mao <maowenan@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

drivers/net/ethernet/mellanox/mlx5/core/fs_core.c

@@ -469,6 +469,7 @@ static void del_hw_fte(struct fs_node *node)
 			mlx5_core_warn(dev,
 				       "flow steering can't delete fte in index %d of flow group id %d\n",
 				       fte->index, fg->id);
+		node->active = 0;
 	}
 }
 
@@ -1595,6 +1596,11 @@ lookup_fte_locked(struct mlx5_flow_group *g,
 		fte_tmp = NULL;
 		goto out;
 	}
+	if (!fte_tmp->node.active) {
+		tree_put_node(&fte_tmp->node);
+		fte_tmp = NULL;
+		goto out;
+	}
 
 	nested_down_write_ref_node(&fte_tmp->node, FS_LOCK_CHILD);
 out: