netdev - Re: [PATCH net-next 4/4] net, neigh: Add NTF_MANAGED flag for managed neighbor entries

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 12 Oct 2021 17:26:52 +0200
From:   Daniel Borkmann <daniel@...earbox.net>
To:     David Ahern <dsahern@...il.com>, davem@...emloft.net,
        kuba@...nel.org, Ido Schimmel <idosch@...sch.org>
Cc:     roopa@...dia.com, dsahern@...nel.org, m@...bda.lt,
        john.fastabend@...il.com, netdev@...r.kernel.org,
        bpf@...r.kernel.org
Subject: Re: [PATCH net-next 4/4] net, neigh: Add NTF_MANAGED flag for managed
 neighbor entries

On 10/12/21 5:05 PM, Daniel Borkmann wrote:
> On 10/12/21 4:51 PM, David Ahern wrote:
>> On 10/11/21 6:12 AM, Daniel Borkmann wrote:
[...]
>>> @@ -1254,8 +1281,8 @@ static int __neigh_update(struct neighbour *neigh, const u8 *lladdr,
>>>           (old & (NUD_NOARP | NUD_PERMANENT)))
>>>           goto out;
>>> -    ext_learn_change = neigh_update_ext_learned(neigh, flags, &notify);
>>> -    if (flags & NEIGH_UPDATE_F_USE) {
>>> +    neigh_update_flags(neigh, flags, &notify, &gc_update, &managed_update);
>>> +    if (flags & (NEIGH_UPDATE_F_USE | NEIGH_UPDATE_F_MANAGED)) {
>>>           new = old & ~NUD_PERMANENT;
>>
>> so a neighbor entry can not be both managed and permanent, but you don't
>> check for the combination in neigh_add and error out with a message to
>> the user.
> 
> Good point, I'll error out if both NUD_PERMANENT and NTF_MANAGED is set in neigh_add().
> 
> Thanks for the review!

Ah, I missed that this was already applied, will send a relative diff in that case.

Thanks,
Daniel