From 199f7d24ae59894243687a234a909f44a8724506 Mon Sep 17 00:00:00 2001 From: James Chapman Date: Wed, 4 Jun 2008 15:07:32 -0700 Subject: [PATCH] lt2p: Fix possible WARN_ON from socket code when UDP socket is closed If an L2TP daemon closes a tunnel socket while packets are queued in the tunnel's reorder queue, a kernel warning is logged because the socket is closed while skbs are still referencing it. The fix is to purge the queue in the socket's release handler. WARNING: at include/net/sock.h:351 udp_lib_unhash+0x41/0x68() Pid: 12998, comm: openl2tpd Not tainted 2.6.25 #8 [] warn_on_slowpath+0x41/0x51 [] udp_lib_unhash+0x41/0x68 [] sk_common_release+0x23/0x90 [] udp_lib_close+0x8/0xa [] inet_release+0x42/0x48 [] sock_release+0x14/0x60 [] sock_close+0x29/0x30 [] __fput+0xad/0x15b [] fput+0x17/0x19 [] filp_close+0x50/0x5a [] sys_close+0x69/0x9f [] syscall_call+0x7/0xb Signed-off-by: James Chapman Signed-off-by: David S. Miller --- drivers/net/pppol2tp.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/net/pppol2tp.c b/drivers/net/pppol2tp.c index 8db342f2fd..04c7e5b407 100644 --- a/drivers/net/pppol2tp.c +++ b/drivers/net/pppol2tp.c @@ -1279,6 +1279,7 @@ out: static int pppol2tp_release(struct socket *sock) { struct sock *sk = sock->sk; + struct pppol2tp_session *session; int error; if (!sk) @@ -1296,9 +1297,18 @@ static int pppol2tp_release(struct socket *sock) sock_orphan(sk); sock->sk = NULL; + session = pppol2tp_sock_to_session(sk); + /* Purge any queued data */ skb_queue_purge(&sk->sk_receive_queue); skb_queue_purge(&sk->sk_write_queue); + if (session != NULL) { + struct sk_buff *skb; + while ((skb = skb_dequeue(&session->reorder_q))) { + kfree_skb(skb); + sock_put(sk); + } + } release_sock(sk); -- 2.39.5