[PATCH 4.16 09/55] net/mlx4_en: Fix an error handling path in mlx4_en_init_netdev()

From: Greg Kroah-Hartman
Date: Fri May 18 2018 - 03:21:08 EST


4.16-stable review patch. If anyone has any objections, please let me know.

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

From: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>

[ Upstream commit a577d868b768a3baf16cdd4841ab8cfb165521d6 ]

If an error occurs, 'mlx4_en_destroy_netdev()' is called.
It then calls 'mlx4_en_free_resources()' which does the needed resources
cleanup.

So, doing some explicit kfree in the error handling path would lead to
some double kfree.

Simplify code to avoid such a case.

Fixes: 67f8b1dcb9ee ("net/mlx4_en: Refactor the XDP forwarding rings scheme")
Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx4/en_netdev.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -3320,12 +3320,11 @@ int mlx4_en_init_netdev(struct mlx4_en_d
MAX_TX_RINGS, GFP_KERNEL);
if (!priv->tx_ring[t]) {
err = -ENOMEM;
- goto err_free_tx;
+ goto out;
}
priv->tx_cq[t] = kzalloc(sizeof(struct mlx4_en_cq *) *
MAX_TX_RINGS, GFP_KERNEL);
if (!priv->tx_cq[t]) {
- kfree(priv->tx_ring[t]);
err = -ENOMEM;
goto out;
}
@@ -3578,11 +3577,6 @@ int mlx4_en_init_netdev(struct mlx4_en_d

return 0;

-err_free_tx:
- while (t--) {
- kfree(priv->tx_ring[t]);
- kfree(priv->tx_cq[t]);
- }
out:
mlx4_en_destroy_netdev(dev);
return err;