From: Guillaume Nault g.nault@alphalink.fr
commit 5e6a9e5a3554a5b3db09cdc22253af1849c65dff upstream.
l2tp_session_find() doesn't take any reference on the returned session. Therefore, the session may disappear while sending the notification.
Use l2tp_session_get() instead and decrement session's refcount once the notification is sent.
Backporting Notes
This is a backport of a backport.
Fixes: 33f72e6f0c67 ("l2tp : multicast notification to the registered listeners") Signed-off-by: Guillaume Nault g.nault@alphalink.fr Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Amit Pundir amit.pundir@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Giuliano Procida gprocida@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/l2tp/l2tp_netlink.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/net/l2tp/l2tp_netlink.c +++ b/net/l2tp/l2tp_netlink.c @@ -626,10 +626,12 @@ static int l2tp_nl_cmd_session_create(st session_id, peer_session_id, &cfg);
if (ret >= 0) { - session = l2tp_session_find(net, tunnel, session_id); - if (session) + session = l2tp_session_get(net, tunnel, session_id, false); + if (session) { ret = l2tp_session_notify(&l2tp_nl_family, info, session, L2TP_CMD_SESSION_CREATE); + l2tp_session_dec_refcount(session); + } }
out: