From mboxrd@z Thu Jan  1 00:00:00 1970
From: roopa <roopa@cumulusnetworks.com>
Subject: Re: [PATCH net] fib_rules: fix fib rule dumps across multiple skbs
Date: Fri, 02 Oct 2015 10:44:22 -0700
Message-ID: <560EC276.3030905@cumulusnetworks.com>
References: <1442983222-42750-1-git-send-email-roopa@cumulusnetworks.com> <CAL1RGDWBJr=D3sRyZTM4VxrPf+Dy35K1DRYCZW9OZSkbtZPhww@mail.gmail.com>
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Cc: David Miller <davem@davemloft.net>, tgraf@suug.ch,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	wkok@cumulusnetworks.com, stable@vger.kernel.org
To: Roland Dreier <roland@purestorage.com>
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On 10/2/15, 10:18 AM, Roland Dreier wrote:
> On Tue, Sep 22, 2015 at 9:40 PM, Roopa Prabhu <roopa@cumulusnetworks.com> wrote:
>> +               err = fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).portid,
>> +                                      cb->nlh->nlmsg_seq, RTM_NEWRULE,
>> +                                      NLM_F_MULTI, ops);
>> +               if (err)
> FWIW I believe this breaks pre-4.0 stable kernels (unfortunately it
> just showed up in 3.10.90).  In kernels without 053c095a82cf
> ("netlink: make nlmsg_end() and genlmsg_end() void") then
> fib_nl_fill_rule() returns a positive value (skb->len) on success, so
> we break out of the loop here immediately.  Symptom is "ip rule show"
> loops forever printing the first rule.
>
> After I finish testing a fix (as trivial as changing to "if (err <
> 0)") here, I'll send it to -stable guys.
>
Thanks for catching this.