[ovs-git] [openvswitch/ovs] fb23ed: flow: Don't include ports of first fragments in hash

[Ben Pfaff]

  Branch: refs/heads/master
  Home:   https://github.com/openvswitch/ovs
  Commit: fb23ed4789cea9bc6ccc13e7c326c5afdd02db22
      https://github.com/openvswitch/ovs/commit/fb23ed4789cea9bc6ccc13e7c326c5afdd02db22
  Author: Van Bemmel, Jeroen (Nokia - US) <jeroen.van_bemmel at nokia.com>
  Date:   2019-06-07 (Fri, 07 Jun 2019)

  Changed paths:
    M lib/flow.c

  Log Message:
  -----------
  flow: Don't include ports of first fragments in hash

For a series of IP fragments, only the first packet includes the transport
header (TCP/UDP/SCTP) and the src/dst ports. By including these port
numbers in the hash, it may happen that a first fragment hashes to a
different value than subsequent packets, causing different packets from
the same flow to follow different paths. This in turn may result in
out-of-order delivery or failed reassembly. This patch excludes port
numbers from the hash calculation in case of IP fragmentation.

Signed-off-by: Jeroen van Bemmel <jeroen.van_bemmel at nokia.com>
Signed-off-by: Ben Pfaff <blp at ovn.org>