Commits
Tom Parkin committed 9980d001cec
l2tp: add udp encap socket destroy handler L2TP sessions hold a reference to the tunnel socket to prevent it going away while sessions are still active. However, since tunnel destruction is handled by the sock sk_destruct callback there is a catch-22: a tunnel with sessions cannot be deleted since each session holds a reference to the tunnel socket. If userspace closes a managed tunnel socket, or dies, the tunnel will persist and it will be neccessary to individually delete the sessions using netlink commands. This is ugly. To prevent this occuring, this patch leverages the udp encapsulation socket destroy callback to gain early notification when the tunnel socket is closed. This allows us to safely close the sessions running in the tunnel, dropping the tunnel socket references in the process. The tunnel socket is then destroyed as normal, and the tunnel resources deallocated in sk_destruct. While we're at it, ensure that l2tp_tunnel_closeall correctly drops session references to allow the sessions to be deleted rather than leaking. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: James Chapman <jchapman@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>