3.16.50-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Guillaume Nault <g.nault@xxxxxxxxxxxx> commit af87ae465abdc070de0dc35d6c6a9e7a8cd82987 upstream. There's no point in checking for duplicate sessions at the beginning of l2tp_nl_cmd_session_create(); the ->session_create() callbacks already return -EEXIST when the session already exists. Furthermore, even if l2tp_session_find() returns NULL, a new session might be created right after the test. So relying on ->session_create() to avoid duplicate session is the only sane behaviour. Signed-off-by: Guillaume Nault <g.nault@xxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> [bwh: Backported to 3.16: also delete the now-unused local variable] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- --- a/net/l2tp/l2tp_netlink.c +++ b/net/l2tp/l2tp_netlink.c @@ -415,7 +415,6 @@ static int l2tp_nl_cmd_session_create(st u32 peer_session_id; int ret = 0; struct l2tp_tunnel *tunnel; - struct l2tp_session *session; struct l2tp_session_cfg cfg = { 0, }; struct net *net = genl_info_net(info); @@ -435,11 +434,6 @@ static int l2tp_nl_cmd_session_create(st goto out; } session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]); - session = l2tp_session_find(net, tunnel, session_id); - if (session) { - ret = -EEXIST; - goto out; - } if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) { ret = -EINVAL;