Re: net: heap out-of-bounds in fib6_clean_node/rt6_fill_node/fib6_age/fib6_prune_clone

[Dmitry Vyukov]

On Thu, Apr 20, 2017 at 1:51 AM, David Ahern <dsa@xxxxxxxxxxxxxxxxxxx> wrote:
> On 4/19/17 5:47 PM, Cong Wang wrote:
>> On Wed, Apr 19, 2017 at 9:12 AM, Andrey Konovalov <andreyknvl@xxxxxxxxxx> wrote:
>>>
>>> Anyway, I just finished simplifying the reproducer. Give this one a try.
>>
>> Thanks for providing such a minimal reproducer!
>>
>> The following patch could fix this crash, but I am not 100% sure if we should
>> just clear these bits or reject them with an errno.
>>
>> diff --git a/net/ipv6/route.c b/net/ipv6/route.c
>> index 9db14189..cf524c2 100644
>> --- a/net/ipv6/route.c
>> +++ b/net/ipv6/route.c
>> @@ -2086,7 +2086,7 @@ static struct rt6_info
>> *ip6_route_info_create(struct fib6_config *cfg)
>>         } else
>>                 rt->rt6i_prefsrc.plen = 0;
>>
>> -       rt->rt6i_flags = cfg->fc_flags;
>> +       rt->rt6i_flags = cfg->fc_flags & ~(RTF_PCPU | RTF_CACHE);
>>
>>  install_route:
>>         rt->dst.dev = dev;
>>
>
> I sent a patch returning EINVAL if RTF_PCPU is set in fc_flags


Andrey, does it fix the other crashes?