The global blackhole_netdev has replaced pernet loopback_dev to become the
one given to the object that holds an netdev when ifdown in many places of
ipv4 and ipv6 since commit 8d7017fd62 ("blackhole_netdev: use
blackhole_netdev to invalidate dst entries").
Especially after commit faab39f63c ("net: allow out-of-order netdev
unregistration"), it's no longer safe to use loopback_dev that may be
freed before other netdev.
This patch is to set dst dev to blackhole_netdev instead of loopback_dev
in ifdown.
v1->v2:
- add Fixes tag as Eric suggested.
Fixes: faab39f63c ("net: allow out-of-order netdev unregistration")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/e8c87482998ca6fcdab214f5a9d582899ec0c648.1652665047.git.lucien.xin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
4d33ab08c0