From a8f8415ccfd9d3cc99eef6342eb1f0e990e8347b Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Fri, 25 Aug 2017 16:51:42 +0200 Subject: [PATCH] l2tp: hold tunnel while handling genl tunnel updates commit 8c0e421525c9eb50d68e8f633f703ca31680b746 upstream. We need to make sure the tunnel is not going to be destroyed by l2tp_tunnel_destruct() concurrently. Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/l2tp/l2tp_netlink.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/l2tp/l2tp_netlink.c b/net/l2tp/l2tp_netlink.c index defaba78d851..6dcb2f54bd72 100644 --- a/net/l2tp/l2tp_netlink.c +++ b/net/l2tp/l2tp_netlink.c @@ -211,8 +211,8 @@ static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info } tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]); - tunnel = l2tp_tunnel_find(net, tunnel_id); - if (tunnel == NULL) { + tunnel = l2tp_tunnel_get(net, tunnel_id); + if (!tunnel) { ret = -ENODEV; goto out; } @@ -220,6 +220,8 @@ static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info if (info->attrs[L2TP_ATTR_DEBUG]) tunnel->debug = nla_get_u32(info->attrs[L2TP_ATTR_DEBUG]); + l2tp_tunnel_dec_refcount(tunnel); + out: return ret; } -- 2.39.5