Re: [PATCH] net/mlx4_en: fix off by one in error handling

Tariq Toukan
2016-09-14T13:43:33Z

Hi Sebastian,

Thanks for this fix.

On 14/09/2016 2:09 PM, Sebastian Ott wrote:
> If an error occurs in mlx4_init_eq_table the index used in the
> err_out_unmap label is one too big which results in a panic in
> mlx4_free_eq. This patch fixes the index in the error path.
You are right, but your change below does not cover all cases.
The full solution looks like this:

@@ -1260,7 +1260,7 @@ int mlx4_init_eq_table(struct mlx4_dev *dev)
eq);
}
if (err)
- goto err_out_unmap;
+ goto err_out_unmap_excluded;
}

if (dev->flags & MLX4_FLAG_MSI_X) {
@@ -1306,8 +1306,10 @@ int mlx4_init_eq_table(struct mlx4_dev *dev)
return 0;

err_out_unmap:
- while (i >= 0)
- mlx4_free_eq(dev, &priv->eq_table.eq[i--]);
+ mlx4_free_eq(dev, &priv->eq_table.eq[i]);
+err_out_unmap_excluded:
+ while (i > 0)
+ mlx4_free_eq(dev, &priv->eq_table.eq[--i]);
#ifdef CONFIG_RFS_ACCEL
for (i = 1; i <= dev->caps.num_ports; i++) {
if (mlx4_priv(dev)->port[i].rmap) {

>
> Signed-off-by: Sebastian Ott <sebott-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
> ---
> drivers/net/ethernet/mellanox/mlx4/eq.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx4/eq.c b/drivers/net/ethernet/mellanox/mlx4/eq.c
> index f613977..cf8f8a7 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/eq.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/eq.c
> @@ -1305,8 +1305,8 @@ int mlx4_init_eq_table(struct mlx4_dev *dev)
> return 0;
>
> err_out_unmap:
> - while (i >= 0)
> - mlx4_free_eq(dev, &priv->eq_table.eq[i--]);
> + while (i > 0)
> + mlx4_free_eq(dev, &priv->eq_table.eq[--i]);
> #ifdef CONFIG_RFS_ACCEL
> for (i = 1; i <= dev->caps.num_ports; i++) {
> if (mlx4_priv(dev)->port[i].rmap) {
You can choose to submit again, or we can take it from here. Whatever
you prefer.

Regards,
Tariq
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html