netdev - Re: [Patch net-next] net_sched: fix an extack message in tcf_block

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] [day] [month] [year] [list]

Date:   Sun, 30 Sep 2018 17:12:16 +0300
From:   Vlad Buslov <vladbu@...lanox.com>
To:     Cong Wang <xiyou.wangcong@...il.com>
Cc:     Linux Kernel Network Developers <netdev@...r.kernel.org>,
        Jiri Pirko <jiri@...nulli.us>,
        Jamal Hadi Salim <jhs@...atatu.com>
Subject: Re: [Patch net-next] net_sched: fix an extack message in tcf_block_find()


On Fri 28 Sep 2018 at 17:03, Cong Wang <xiyou.wangcong@...il.com> wrote:
> On Fri, Sep 28, 2018 at 4:36 AM Vlad Buslov <vladbu@...lanox.com> wrote:
>>
>> On Thu 27 Sep 2018 at 20:42, Cong Wang <xiyou.wangcong@...il.com> wrote:
>> > It is clearly a copy-n-paste.
>> >
>> > Signed-off-by: Cong Wang <xiyou.wangcong@...il.com>
>> > ---
>> >  net/sched/cls_api.c | 2 +-
>> >  1 file changed, 1 insertion(+), 1 deletion(-)
>> >
>> > diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
>> > index 3de47e99b788..8dd7f8af6d54 100644
>> > --- a/net/sched/cls_api.c
>> > +++ b/net/sched/cls_api.c
>> > @@ -655,7 +655,7 @@ static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
>> >
>> >               *q = qdisc_refcount_inc_nz(*q);
>> >               if (!*q) {
>> > -                     NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
>> > +                     NL_SET_ERR_MSG(extack, "Can't increase Qdisc refcount");
>> >                       err = -EINVAL;
>> >                       goto errout_rcu;
>> >               }
>>
>> Is there a benefit in exposing this info to user?
>
> Depends on what user you mean here. For kernel developers, yes,
> this is useful. For others, no.
>
>
>> For all intents and purposes Qdisc is gone at that point.
>
> I don't want to be a language lawyer, but there is a difference between
> "it doesn't exist" and "it exists but being removed". The errno EINVAL
> betrays what you said too, it must be ENOENT to mach "Qdisc is gone".
>
> I don't want to waste my time on this any more. Let's just drop it.
>
> I really don't care, do you?

I'm asked the question in order to improve error messages in my future
patches, not because I care about this particular string.