Re: [PATCH net 0/4] vxlan: fix default fdb entry user-space notify ordering/race
From: Roopa Prabhu
Date: Fri, 20 Jul 2018 13:21:00 -0700
> From: Roopa Prabhu
>
> Problem:
> In vxlan_newlink, a default fdb entry is added before register_netdev.
> The default fdb creation function notifies user-space of the
> fdb entry on the vxlan device which user-space does not know about yet.
> (RTM_NEWNEIGH goes before RTM_NEWLINK for the same ifindex).
>
> This series fixes the user-space netlink notification ordering issue
> with the following changes:
> - decouple fdb notify from fdb create.
> - Move fdb notify after register_netdev.
> - modify rtnl_configure_link to allow configuring a link early.
> - Call rtnl_configure_link in vxlan newlink handler to notify
> userspace about the newlink before fdb notify and
> hence avoiding the user-space race.
>
> Fixes: afbd8bae9c79 ("vxlan: add implicit fdb entry for default destination")
> Signed-off-by: Roopa Prabhu
Series applied and queued up for -stable, thanks Roopa.
Re: [PATCH net 0/4] vxlan: fix default fdb entry user-space notify ordering/race
On Fri, Jul 20, 2018 at 1:21 PM, Roopa Prabhu wrote:
> From: Roopa Prabhu
>
> Problem:
> In vxlan_newlink, a default fdb entry is added before register_netdev.
> The default fdb creation function notifies user-space of the
> fdb entry on the vxlan device which user-space does not know about yet.
> (RTM_NEWNEIGH goes before RTM_NEWLINK for the same ifindex).
>
> This series fixes the user-space netlink notification ordering issue
> with the following changes:
> - decouple fdb notify from fdb create.
> - Move fdb notify after register_netdev.
> - modify rtnl_configure_link to allow configuring a link early.
> - Call rtnl_configure_link in vxlan newlink handler to notify
> userspace about the newlink before fdb notify and
> hence avoiding the user-space race.
>
> Fixes: afbd8bae9c79 ("vxlan: add implicit fdb entry for default destination")
> Signed-off-by: Roopa Prabhu
Just noticed that my email editor is greying out/hiding the note i
added for this series. repasting here so that its not missed:
Dave, I am sending this series against net on your request on my
net-next series.
https://marc.info/?l=linux-netdev=153098151929102=2
I did not know how long to wait before i send it to net. So sending it now.
As you also noted it is a very old bug. If you have changed your mind
about stable or
if this is too early for net and you think we should soak it more in net-next,
pls feel free to drop. also, i will be happy to do a stable backport
if needed. thanks.
[PATCH net 0/4] vxlan: fix default fdb entry user-space notify ordering/race
From: Roopa Prabhu
Problem:
In vxlan_newlink, a default fdb entry is added before register_netdev.
The default fdb creation function notifies user-space of the
fdb entry on the vxlan device which user-space does not know about yet.
(RTM_NEWNEIGH goes before RTM_NEWLINK for the same ifindex).
This series fixes the user-space netlink notification ordering issue
with the following changes:
- decouple fdb notify from fdb create.
- Move fdb notify after register_netdev.
- modify rtnl_configure_link to allow configuring a link early.
- Call rtnl_configure_link in vxlan newlink handler to notify
userspace about the newlink before fdb notify and
hence avoiding the user-space race.
Fixes: afbd8bae9c79 ("vxlan: add implicit fdb entry for default destination")
Signed-off-by: Roopa Prabhu
Roopa Prabhu (4):
vxlan: add new fdb alloc and create helpers
vxlan: make netlink notify in vxlan_fdb_destroy optional
rtnetlink: add rtnl_link_state check in rtnl_configure_link
vxlan: fix default fdb netlink notify ordering during netdev create
drivers/net/vxlan.c | 130 ++-
net/core/rtnetlink.c | 9 ++--
2 files changed, 94 insertions(+), 45 deletions(-)
--
Dave, I am sending this series against net on your request on my net-next
series.
https://marc.info/?l=linux-netdev=153098151929102=2
I did not know how long to wait before i send it to net. So sending it now.
As you also noted it is a very old bug. If you have changed your mind about
stable or
if this is too early for net and you think we should soak it more in net-next,
pls feel free to drop. also, i will be happy to do a stable backport if needed.
thanks.
