[PATCH] net: mlx5: vport: Add error handling in mlx5_query_nic_vport_node_guid()

[Wentao Liang]

The function mlx5_query_nic_vport_node_guid() calls the functuion
mlx5_query_nic_vport_context() but does not check its return value.
A proper implementation can be found in mlx5_nic_vport_query_local_lb().

Add error handling for mlx5_query_nic_vport_context(). If it fails, free
the out buffer via kvfree() and return error code.

Fixes: 9efa75254593 ("net/mlx5_core: Introduce access functions to query vport RoCE fields")
Cc: stable@xxxxxxxxxxxxxxx # v4.5
Signed-off-by: Wentao Liang <vulab@xxxxxxxxxxx>
---
 drivers/net/ethernet/mellanox/mlx5/core/vport.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/vport.c b/drivers/net/ethernet/mellanox/mlx5/core/vport.c
index 276b162ccf18..db45ad72ff43 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/vport.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/vport.c
@@ -464,20 +464,23 @@ int mlx5_query_nic_vport_sd_group(struct mlx5_core_dev *mdev, u8 *sd_group)
 int mlx5_query_nic_vport_node_guid(struct mlx5_core_dev *mdev, u64 *node_guid)
 {
 	u32 *out;
-	int outlen = MLX5_ST_SZ_BYTES(query_nic_vport_context_out);
+	int ret, outlen = MLX5_ST_SZ_BYTES(query_nic_vport_context_out);
 
 	out = kvzalloc(outlen, GFP_KERNEL);
 	if (!out)
 		return -ENOMEM;
 
-	mlx5_query_nic_vport_context(mdev, 0, out);
+	ret = mlx5_query_nic_vport_context(mdev, 0, out);
+	if (ret)
+		goto err;
 
 	*node_guid = MLX5_GET64(query_nic_vport_context_out, out,
 				nic_vport_context.node_guid);
-
+	ret = 0;
+err:
 	kvfree(out);
 
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(mlx5_query_nic_vport_node_guid);
 
-- 
2.42.0.windows.2