In the Linux kernel, the following vulnerability has been resolved:net: gso: fix ownership in __udp_gso_segmentIn __udp_gso_segment the skb destructor is removed before segmenting the
skb but the socket reference is kept as-is. This is an issue if the
original skb is later orphaned as we can hit the following bug:kernel BUG at ./include/linux/skbuff.h:3312!  (skb_orphan)
  RIP: 0010:ip_rcv_core+0x8b2/0xca0
  Call Trace:
   ip_rcv+0xab/0x6e0
   __netif_receive_skb_one_core+0x168/0x1b0
   process_backlog+0x384/0x1100
   __napi_poll.constprop.0+0xa1/0x370
   net_rx_action+0x925/0xe50The above can happen following a sequence of events when using
OpenVSwitch, when an OVS_ACTION_ATTR_USERSPACE action precedes an
OVS_ACTION_ATTR_OUTPUT action:OVS_ACTION_ATTR_USERSPACE is handled (in do_execute_actions): the skb
goes through queue_gso_packets and then __udp_gso_segment, where its
destructor is removed.The segments' data are copied and sent to userspace.OVS_ACTION_ATTR_OUTPUT is handled (in do_execute_actions) and the
same original skb is sent to its path.If it later hits skb_orphan, we hit the bug.Fix this by also removing the reference to the socket in
__udp_gso_segment.