From: Guillaume Nault <g.nault@alphalink.fr>
Date: Fri, 25 Aug 2017 16:51:42 +0200
Subject: l2tp: hold tunnel while processing genl delete command
Patch-mainline: v4.13
Git-commit: bb0a32ce4389e17e47e198d2cddaf141561581ad
References: bsc#1076830
l2tp_nl_cmd_tunnel_delete() needs to take a reference on the tunnel, to
prevent it from being concurrently freed by l2tp_tunnel_destruct().
Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP")
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Michal Kubecek <mkubecek@suse.cz>
---
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 abfcfbd34776..19d4ef1e5f2f 100644
--- a/net/l2tp/l2tp_netlink.c
+++ b/net/l2tp/l2tp_netlink.c
@@ -273,8 +273,8 @@ static int l2tp_nl_cmd_tunnel_delete(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;
}
@@ -284,6 +284,8 @@ static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info
(void) l2tp_tunnel_delete(tunnel);
+ l2tp_tunnel_dec_refcount(tunnel);
+
out:
return ret;
}
--
2.16.1