1. 16 Mar, 2016 1 commit
    • Johannes Berg's avatar
      wext: fix message delay/ordering · 7c20cf58
      Johannes Berg authored
      commit 8bf86273 upstream.
      
      Beniamino reported that he was getting an RTM_NEWLINK message for a
      given interface, after the RTM_DELLINK for it. It turns out that the
      message is a wireless extensions message, which was sent because the
      interface had been connected and disconnection while it was deleted
      caused a wext message.
      
      For its netlink messages, wext uses RTM_NEWLINK, but the message is
      without all the regular rtnetlink attributes, so "ip monitor link"
      prints just rudimentary information:
      
      5: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default
          link/ether 02:00:00:00:01:00 brd ff:ff:ff:ff:ff:ff
      Deleted 5: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default
          link/ether 02:00:00:00:01:00 brd ff:ff:ff:ff:ff:ff
      5: wlan1: <BROADCAST,MULTICAST,UP>
          link/ether
      (from my hwsim reproduction)
      
      This can cause userspace to get confused since it doesn't expect an
      RTM_NEWLINK message after RTM_DELLINK.
      
      The reason for this is that wext schedules a worker to send out the
      messages, and the scheduling delay can cause the messages to get out
      to userspace in different order.
      
      To fix this, have wext register a netdevice notifier and flush out
      any pending messages when netdevice state changes. This fixes any
      ordering whenever the original message wasn't sent by a notifier
      itself.
      Reported-by: default avatarBeniamino Galvani <bgalvani@redhat.com>
      Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      7c20cf58
  2. 15 Mar, 2016 2 commits
  3. 11 Mar, 2016 1 commit
  4. 09 Mar, 2016 36 commits