Re: [PATCH][net-next] nexthop: fix incorrect allocation failure on nhg->spare

[Colin Ian King]

On 28/05/2020 16:55, Nikolay Aleksandrov wrote:
> On 28/05/2020 18:53, Colin Ian King wrote:
>> On 28/05/2020 15:55, Nikolay Aleksandrov wrote:
>>> On 28/05/2020 17:53, Nikolay Aleksandrov wrote:
>>>> On 28/05/2020 17:51, Colin King wrote:
>>>>> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>>>>>
>>>>> The allocation failure check for nhg->spare is currently checking
>>>>> the pointer nhg rather than nhg->spare which is never false. Fix
>>>>> this by checking nhg->spare instead.
>>>>>
>>>>> Addresses-Coverity: ("Logically dead code")
>>>>> Fixes: 430a049190de ("nexthop: Add support for nexthop groups")
>>>>> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>>>>> ---
>>>>>  net/ipv4/nexthop.c | 2 +-
>>>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c
>>>>> index ebafa5ed91ac..97423d6f2de9 100644
>>>>> --- a/net/ipv4/nexthop.c
>>>>> +++ b/net/ipv4/nexthop.c
>>>>> @@ -1185,7 +1185,7 @@ static struct nexthop *nexthop_create_group(struct net *net,
>>>>>  
>>>>>  	/* spare group used for removals */
>>>>>  	nhg->spare = nexthop_grp_alloc(num_nh);
>>>>> -	if (!nhg) {
>>>>> +	if (!nhg->spare) {
>>>>>  		kfree(nhg);
>>>>>  		kfree(nh);
>>>>>  		return NULL;
>>>>>
>>>>
>>>> Good catch, embarrassing copy paste error :-/
>>>> Acked-by: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx>
>>>>
>>>
>>> Wait - that should be targeted at -net, that's where the fixes went.
>>> And the fixes tag is wrong, nhg->spare was very recently added by:
>>> commit 90f33bffa382
>>> Author: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx>
>>> Date:   Tue May 26 12:56:15 2020 -0600
>>>
>>>     nexthops: don't modify published nexthop groups
>>>
>>
>> Do you require me to fix this up and re-send?
>>
>> Colin
>>
> 
> Up to you, it will go to the same stable releases as that fix used the same
> Fixes tag, so it's really not an issue.
> 
OK, I'll let it slip and won't send a V2. Thanks