Re: [PATCH] e1000: avoid null pointer dereference on invalid stat type

From: Colin Ian King
Date: Fri Sep 22 2017 - 07:55:23 EST


On 22/09/17 12:50, Dan Carpenter wrote:
> On Thu, Sep 21, 2017 at 11:01:58PM +0100, Colin King wrote:
>> @@ -1837,12 +1838,13 @@ static void e1000_get_ethtool_stats(struct net_device *netdev,
>> p = (char *)adapter + stat->stat_offset;
>> break;
>> default:
>> + p = NULL;
>> WARN_ONCE(1, "Invalid E1000 stat type: %u index %d\n",
>> stat->type, i);
>> break;
>> }
>>
>> - if (stat->sizeof_stat == sizeof(u64))
>> + if (p && stat->sizeof_stat == sizeof(u64))
>> data[i] = *(u64 *)p;
>> else
>> data[i] = *(u32 *)p;
> ^^^^^^^^
>
> The else side will still crash.
>
> regards,
> dan carpenter
>
Thanks, stupid me. I'll fix that up.