Re: [PATCH] staging: wilc1000: check for kmalloc allocation failures

From: Colin Ian King
Date: Mon Mar 26 2018 - 12:16:02 EST


On 26/03/18 16:35, Ajay Singh wrote:
> Thanks for submitting the patch.
>
> On Wed, 21 Mar 2018 13:03:18 -0700
> Joe Perches <joe@xxxxxxxxxxx> wrote:
>
>> On Wed, 2018-03-21 at 19:19 +0000, Colin King wrote:
>>> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>>>
>>> There are three kmalloc allocations that are not null checked which
>>> potentially could lead to null pointer dereference issues. Fix this
>>> by adding null pointer return checks.
>>
>> looks like all of these should be kmemdup or kstrdup
>>
>>>
>>> @@ -951,6 +955,10 @@ static s32 handle_connect(struct wilc_vif *vif,
>>> if (conn_attr->ssid) {
>>> hif_drv->usr_conn_req.ssid = kmalloc(conn_attr->ssid_len + 1,
>>> GFP_KERNEL);
>>> + if (!hif_drv->usr_conn_req.ssid) {
>>> + result = -ENOMEM;
>>> + goto error;
>>> + }
>>> memcpy(hif_drv->usr_conn_req.ssid,
>>> conn_attr->ssid,
>>> conn_attr->ssid_len);
>
> With this changes the Coverity reported warning is handled correctly.
>
> For further improvement to the patch, as Joe Perches suggested, its better
> to make use of kmemdup instead of kmalloc & memcpy. As kstrdup requires the
> source string to be NULL terminated('\0') and conn_attr->ssid might not
> contains the '\0' terminated string. So kmemdup with length of
> 'conn_attr->ssid_len' can be used instead.
>
> Please include the changes by using kmemdup() for all kmalloc/memcpy in
> this patch.

The original has been included into Greg's staging repo, so I'll send a
send patch that addresses the kmemdup.

Colin
>
>
>
> Regards,
> Ajay
>