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

Tariq Toukan
2016-09-14T14:49:49Z

On 14/09/2016 4:53 PM, Sebastian Ott wrote:
> Hello Tariq,
>
> On Wed, 14 Sep 2016, Tariq Toukan wrote:
>> 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;
> In this case a call to mlx4_create_eq failed. Do you really have to call
> mlx4_free_eq for this index again?
We agree on this part, that's why here we should goto the _excluded_ label.
For all other parts, we should not exclude the eq in the highest index,
and thus we goto the _non_excluded_ label.
> As far as I understood this code
> mlx4_create_eq cleans up when it fails and thus there is no need for an
> additional mlx4_free_eq call.
>
> Regards,
> Sebastian
>
Regards,
Tariq