From d03f228470a8c0a22b774d1f8d47071e0de4f6dd Mon Sep 17 00:00:00 2001 From: Xiyu Yang <xiyuyang19@fudan.edu.cn> Date: Wed, 15 Apr 2020 16:36:19 +0800 Subject: [PATCH] net: netrom: Fix potential nr_neigh refcnt leak in nr_add_node nr_add_node() invokes nr_neigh_get_dev(), which returns a local reference of the nr_neigh object to "nr_neigh" with increased refcnt. When nr_add_node() returns, "nr_neigh" becomes invalid, so the refcount should be decreased to keep refcount balanced. The issue happens in one normal path of nr_add_node(), which forgets to decrease the refcnt increased by nr_neigh_get_dev() and causes a refcnt leak. It should decrease the refcnt before the function returns like other normal paths do. Fix this issue by calling nr_neigh_put() before the nr_add_node() returns. Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn> Signed-off-by: Xin Tan <tanxin.ctf@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- net/netrom/nr_route.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/netrom/nr_route.c b/net/netrom/nr_route.c index 79f12d8c7b86f..0891ee02ca4fe 100644 --- a/net/netrom/nr_route.c +++ b/net/netrom/nr_route.c @@ -208,6 +208,7 @@ static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic, /* refcount initialized at 1 */ spin_unlock_bh(&nr_node_list_lock); + nr_neigh_put(nr_neigh); return 0; } nr_node_lock(nr_node);