From a06998b88b1651c5f71c0e35f528bf2057188ead Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 7 Jun 2012 00:07:20 +0000 Subject: net: l2tp_eth: fix kernel panic on rmmod l2tp_eth We must prevent module unloading if some devices are still attached to l2tp_eth driver. Signed-off-by: Eric Dumazet Reported-by: Denys Fedoryshchenko Tested-by: Denys Fedoryshchenko Cc: James Chapman Signed-off-by: David S. Miller --- net/l2tp/l2tp_eth.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'net/l2tp') diff --git a/net/l2tp/l2tp_eth.c b/net/l2tp/l2tp_eth.c index 443591d629ca..185f12f4a5fa 100644 --- a/net/l2tp/l2tp_eth.c +++ b/net/l2tp/l2tp_eth.c @@ -162,6 +162,7 @@ static void l2tp_eth_delete(struct l2tp_session *session) if (dev) { unregister_netdev(dev); spriv->dev = NULL; + module_put(THIS_MODULE); } } } @@ -249,6 +250,7 @@ static int l2tp_eth_create(struct net *net, u32 tunnel_id, u32 session_id, u32 p if (rc < 0) goto out_del_dev; + __module_get(THIS_MODULE); /* Must be done after register_netdev() */ strlcpy(session->ifname, dev->name, IFNAMSIZ); -- cgit v1.2.3 From 4399a4df98a63e30fd16e9d0cecc46ea92269e8f Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 8 Jun 2012 06:25:00 +0000 Subject: l2tp: fix a race in l2tp_ip_sendmsg() Commit 081b1b1bb27f (l2tp: fix l2tp_ip_sendmsg() route handling) added a race, in case IP route cache is disabled. In this case, we should not do the dst_release(&rt->dst), since it'll free the dst immediately, instead of waiting a RCU grace period. Signed-off-by: Eric Dumazet Cc: James Chapman Cc: Denys Fedoryshchenko Signed-off-by: David S. Miller --- net/l2tp/l2tp_ip.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'net/l2tp') diff --git a/net/l2tp/l2tp_ip.c b/net/l2tp/l2tp_ip.c index 70614e7affab..61d8b75d2686 100644 --- a/net/l2tp/l2tp_ip.c +++ b/net/l2tp/l2tp_ip.c @@ -464,10 +464,12 @@ static int l2tp_ip_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *m sk->sk_bound_dev_if); if (IS_ERR(rt)) goto no_route; - if (connected) + if (connected) { sk_setup_caps(sk, &rt->dst); - else - dst_release(&rt->dst); /* safe since we hold rcu_read_lock */ + } else { + skb_dst_set(skb, &rt->dst); + goto xmit; + } } /* We dont need to clone dst here, it is guaranteed to not disappear. @@ -475,6 +477,7 @@ static int l2tp_ip_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *m */ skb_dst_set_noref(skb, &rt->dst); +xmit: /* Queue the packet to IP for output */ rc = ip_queue_xmit(skb, &inet->cork.fl); rcu_read_unlock(); -- cgit v1.2.3