Message ID | 1587819994-40137-1-git-send-email-xiyuyang19@fudan.edu.cn |
---|---|
State | Accepted |
Delegated to: | David Miller |
Headers | show |
Series | [v2] net/x25: Fix x25_neigh refcnt leak when x25 disconnect | expand |
From: Xiyu Yang <xiyuyang19@fudan.edu.cn> Date: Sat, 25 Apr 2020 21:06:25 +0800 > x25_connect() invokes x25_get_neigh(), which returns a reference of the > specified x25_neigh object to "x25->neighbour" with increased refcnt. > > When x25 connect success and returns, the reference still be hold by > "x25->neighbour", so the refcount should be decreased in > x25_disconnect() to keep refcount balanced. > > The reference counting issue happens in x25_disconnect(), which forgets > to decrease the refcnt increased by x25_get_neigh() in x25_connect(), > causing a refcnt leak. > > Fix this issue by calling x25_neigh_put() before x25_disconnect() > returns. > > Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn> > Signed-off-by: Xin Tan <tanxin.ctf@gmail.com> Applied.
diff --git a/net/x25/x25_subr.c b/net/x25/x25_subr.c index 8aa415a38814..8b1b06cabcbf 100644 --- a/net/x25/x25_subr.c +++ b/net/x25/x25_subr.c @@ -357,6 +357,10 @@ void x25_disconnect(struct sock *sk, int reason, unsigned char cause, sk->sk_state_change(sk); sock_set_flag(sk, SOCK_DEAD); } + read_lock_bh(&x25_list_lock); + x25_neigh_put(x25->neighbour); + x25->neighbour = NULL; + read_unlock_bh(&x25_list_lock); } /*