[libvirt] [PATCH] network: get vlan info for Open vSwitch interfaces from proper source

[Kyle Mestery (kmestery)]

On Aug 29, 2012, at 6:19 AM, Alex Jia wrote:
> On 08/29/2012 06:43 PM, Laine Stump wrote:
>> This bug was revealed by the crash described in
>> 
>>   https://bugzilla.redhat.com/show_bug.cgi?id=852383
>> 
>> The vlan info pointer sent to virNetDevOpenvswitchAddPort should never
>> be non-NULL unless there is at least one tag. The factthat such a vlan
>> info pointer was receveid pointed out that a caller was passing the
>> wrong pointer. Instead of sending&net->vlan, the result of
>> virDomainNetGetActualVlan(net) should be sent - that function will
>> look for vlan info in net->data.network.actual->vlan, and in cany case
>> return NULL instead of a pointer if the vlan info it finds has no
>> tags.
>> 
>> Aside from causing the crash, sending a hardcoded&net->vlan has the
>> effect of ignoring vlan info from a<network>  or<portgroup>  config.
>> ---
>> 
>> Since I'm not online in a regular fashion for the next few days (too
>> bad I wasn't online in the 12 hours or so *before* the 0.10.0 release
>> instead of after :-/), I would appreciate if whoever ACKs this could
>> push it. Thanks!
> 
> Laine, unfortunately, the libvirtd still is crash without my patch after applying your patch :(
> 
Hi Alex and Laine:

What I notice is, that with Laine's patch, for virtualport of type openvswitch, if I do NOT define
a VLAN, it crashes. If I do, then I can start my virtual machines. Without Laine's patch, it's the
same, which leads me to believe Laine's patch only fixes a symptom of this issue.

I'm looking into this now, will see how far I get with it today. But it appears to me to be a bug
in the logic which is handling VLANs at a higher layer.

Thanks,
Kyle

>>  src/qemu/qemu_command.c | 2 +-
>>  src/uml/uml_conf.c      | 2 +-
>>  2 files changed, 2 insertions(+), 2 deletions(-)
>> 
>> diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
>> index 8c32a4d..25f2451 100644
>> --- a/src/qemu/qemu_command.c
>> +++ b/src/qemu/qemu_command.c
>> @@ -258,7 +258,7 @@ qemuNetworkIfaceConnect(virDomainDefPtr def,
>>      err = virNetDevTapCreateInBridgePort(brname,&net->ifname,&net->mac,
>>                                           def->uuid,&tapfd,
>>                                           virDomainNetGetActualVirtPortProfile(net),
>> -&net->vlan,
>> +                                         virDomainNetGetActualVlan(net),
>>                                           tap_create_flags);
>>      virDomainAuditNetDevice(def, net, "/dev/net/tun", tapfd>= 0);
>>      if (err<  0) {
>> diff --git a/src/uml/uml_conf.c b/src/uml/uml_conf.c
>> index 5461b42..410f3e2 100644
>> --- a/src/uml/uml_conf.c
>> +++ b/src/uml/uml_conf.c
>> @@ -141,7 +141,7 @@ umlConnectTapDevice(virConnectPtr conn,
>>      if (virNetDevTapCreateInBridgePort(bridge,&net->ifname,&net->mac,
>>                                         vm->uuid, NULL,
>>                                         virDomainNetGetActualVirtPortProfile(net),
>> -&net->vlan,
>> +                                       virDomainNetGetActualVlan(net),
>>                                         VIR_NETDEV_TAP_CREATE_IFUP)<  0) {
>>          if (template_ifname)
>>              VIR_FREE(net->ifname);