Tunnel config can be accessed by multiple threads at the same time and
it is supposed to be protected by the netdev_vport mutex. However,
many functions are getting direct access to it via netdev API without
taking the mutex, creating a potential for various race conditions.
Fix that by protecting the tunnel config with RCU. The whole structure
is replaced on configuration changes. Individual fields are never
updated and the structure itself is constant. This way it can be safely
used by different threads within RCU grace period.
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
GRE sequence number is maintained as part of the tunnel config.
This triggers tunnel reconfiguration every time set_tunnel_config()
is called, because memset over tunnel config will never be equal to
the new config constructed from database options.
And sequence number incremented non-atomically without holding a
mutex on tunnel push, that may lead to corruption if multiple
threads are sending packets to the same tunnel.
Fix that by moving sequence number to the netdev_vport structure
instead and using an atomic counter.
Fixes: 0ffff49753 ("userspace: add gre sequence number support.")
Fixes: 7dc18ae96d ("userspace: add erspan tunnel support.")
Fixes: 3c6d05a02e ("userspace: Add GTP-U support.")
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Throughout the years, changes in netdev vport have removed the need for some of
the headers, like shash, hmap, and many others. With the recent split of
push/pop code, less headers are needed in each of the two modules.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@redhat.com>
Signed-off-by: Jesse Gross <jesse@kernel.org>
It is better to move tunnel push-pop action specific functions into
separate module.
Signed-off-by: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Jesse Gross <jesse@kernel.org>
