From: Josef Bacik <jbacik@fb.com>
To: Chuck Ebbert <cebbert.lkml@gmail.com>
CC: Laura Abbott <labbott@redhat.com>,
        "David S. Miller" <davem@davemloft.net>,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        "Hideaki YOSHIFUJI" <yoshfuji@linux-ipv6.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Cole Robinson <crobinso@redhat.com>
Subject: Re: 319554f284dd ("inet: don't use sk_v6_rcv_saddr directly") causes
 bind port regression
Thread-Topic: 319554f284dd ("inet: don't use sk_v6_rcv_saddr directly") causes
 bind port regression
Thread-Index: AQHTLBeHTmXbYNNlokyw2o+Z43qCfKKxnfiAgAFYTgD//6eWgIAAnFEAgAAGhGg=
Date: Wed, 13 Sep 2017 20:11:09 +0000
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        <EF55EF02-AD40-4F06-8C07-4F9F4221BFE6@fb.com>,<20170913154750.100881c0@gmail.com>
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> On Sep 13, 2017, at 12:46 PM, Chuck Ebbert <cebbert.lkml@gmail.com> wrote:
> 
> On Wed, 13 Sep 2017 17:28:25 +0000
> Josef Bacik <jbacik@fb.com> wrote:
> 
>> Sorry I thought I had made this other fix, can you apply this on top
>> of the other one and try that?  I have more things to try if this
>> doesn’t work, sorry you are playing go between, but I want to make
>> sure I know _which_ fix actually fixes the problem, and then clean up
>> in followup patches.  Thanks,
>> 
>> Josef
>> 
>> On 9/13/17, 8:45 AM, "Laura Abbott" <labbott@redhat.com> wrote:
>> 
>> On 09/12/2017 04:12 PM, Josef Bacik wrote:
>>> First I’m super sorry for the top post, I’m at plumbers and I
>>> forgot to upload my muttrc to my new cloud instance, so I’m screwed
>>> using outlook.
>>> 
>>> I have a completely untested, uncompiled patch that I think will
>>> fix the problem, would you mind giving it a go?  Thanks,
>>> 
>>> Josef  
>> 
>> Thanks for the quick turnaround. Unfortunately, the problem is still
>> reproducible according to the reporter.
>> 
>> Thanks,
>> Laura
> 
> I am confused by the patch that originally caused this:
> 
>        if (sk->sk_family == AF_INET6)
>                return ipv6_rcv_saddr_equal(&sk->sk_v6_rcv_saddr,
> -                                           &sk2->sk_v6_rcv_saddr,
> +                                           inet6_rcv_saddr(sk2),
>                                            sk->sk_rcv_saddr,
>                                            sk2->sk_rcv_saddr,
> 
> Shouldn't the first argument also be changed to use inet6_rcv_saddr()?

No we know sk is IPv6 so it's alright to use directly.  Thanks,

Josef