[PATCH 1/1] P2P: Ignore RTM_NEWLINK event for the P2P Discovery Interface

[Dmitry Shmidt]

On Fri, Jun 13, 2014 at 4:10 PM, Dmitry Shmidt <dimitrysh at google.com> wrote:
> On Wed, Jun 11, 2014 at 2:30 PM, Jouni Malinen <j at w1.fi> wrote:
>> On Mon, Jun 09, 2014 at 01:26:42AM -0700, Jithu Jance wrote:
>>> Patch for Ignoring the RTM event for the dedicated P2P discovery
>>> Interface. Without the patch the IFFUP operation on the interface
>>> was failing (since there is no network device associated with the
>>> interface).
>>
>>> +     if (drv->nlmode == NL80211_IFTYPE_P2P_DEVICE) {
>>> +             wpa_printf(MSG_INFO, "nl80211: Ignore RTM_NEWLINK for P2P Discovery Interface");
>>> +             return;
>>> +     }
>>
>> Hmm.. How does NL82011_IFTYPE_P2P_DEVICE even get a RTM_NEWLINK event?
>> The main point of that was to not have a netdev.. Could you please share
>> a debug log showing what this looks like without this change?
>
> I think RTM_NEWLINK is received for group interface but this code fails it:
>
> if (!drv->if_disabled && !(ifi->ifi_flags & IFF_UP)) {
>                 if (if_indextoname(ifi->ifi_index, namebuf) &&
>                     linux_iface_up(drv->global->ioctl_sock,
>                                    drv->first_bss->ifname) > 0) {  <<<< Here !!!
>                         wpa_printf(MSG_DEBUG, "nl80211: Ignore interface down "
>                                    "event since interface %s is up", namebuf);
>                         return;
>                 }
>                 wpa_printf(MSG_DEBUG, "nl80211: Interface down");
>
>
> Because namebuf == p2p-wlan0-0 and drv->first_bss->ifname == p2p-dev-wlan0,
> where p2p-wlan0-0 is group interface, and p2p-dev-wlan0 is Non-NETDEV p2p.

It looks like this change
  http://hostap.epitest.fi/cgit/hostap/commit/?id=b36935be1a14341771b0fd5491808c3f6fdcb603
causes nl80211_find_drv() to return wrong pointer.

>
>>
>> --
>> Jouni Malinen                                            PGP id EFC895FA
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