[ovs-git] [openvswitch/ovs] 5a6bec: ip6_gre: Fix a bug that clears address bits

[yifsun]

  Branch: refs/heads/branch-2.10
  Home:   https://github.com/openvswitch/ovs
  Commit: 5a6becdc69b254e6f0e1d5478f1608d81b634590
      https://github.com/openvswitch/ovs/commit/5a6becdc69b254e6f0e1d5478f1608d81b634590
  Author: Yifeng Sun <pkusunyifeng at gmail.com>
  Date:   2019-06-07 (Fri, 07 Jun 2019)

  Changed paths:
    M datapath/linux/compat/ip6_gre.c

  Log Message:
  -----------
  ip6_gre: Fix a bug that clears address bits

In compatible gre module, skb->cb is solely used as ovs_gso_cb.
However, IPCB(skb) also points to skb->cb. IPCB(skb)->flags overlaps
with ovs_gso_cb.tun_dst. As a result, this bug clears the 16-23 bit
in the address of ovs_gso_cb.tun_dst and causes kernel to crash.

Signed-off-by: Yifeng Sun <pkusunyifeng at gmail.com>
Signed-off-by: Ben Pfaff <blp at ovn.org>
Tested-by: Greg Rose <gvrose8192 at gmail.com>
Reviewed-by: Greg Rose <gvrose8192 at gmail.com>