From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexey Dobriyan Subject: [PATCH] af_key: fix netns ops ordering on module load/unload Date: Sat, 30 Jan 2010 14:53:27 +0200 Message-ID: <20100130125327.GA4258@x200> References: <20100129094822.GA8294@nb-core2.darkstar.lan> <1264778549.3184.28.camel@edumazet-laptop> <1264782806.3184.42.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Luca Tettamanti , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, David Miller To: Eric Dumazet Return-path: Content-Disposition: inline In-Reply-To: <1264782806.3184.42.camel@edumazet-laptop> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, Jan 29, 2010 at 05:33:26PM +0100, Eric Dumazet wrote: > @@ -3807,21 +3807,24 @@ static int __init ipsec_pfkey_init(void) > if (err != 0) > goto out; > > - err = sock_register(&pfkey_family_ops); > - if (err != 0) > - goto out_unregister_key_proto; > err = xfrm_register_km(&pfkeyv2_mgr); > if (err != 0) > - goto out_sock_unregister; > + goto out_unregister_key_proto; > + > err = register_pernet_subsys(&pfkey_net_ops); > if (err != 0) > goto out_xfrm_unregister_km; > + > + err = sock_register(&pfkey_family_ops); > + if (err != 0) > + goto out_unregister_pernet; > out: > return err; > + > +out_unregister_pernet: > + unregister_pernet_subsys(&pfkey_net_ops); > out_xfrm_unregister_km: > xfrm_unregister_km(&pfkeyv2_mgr); > -out_sock_unregister: > - sock_unregister(PF_KEY); > out_unregister_key_proto: > proto_unregister(&key_proto); > goto out; ACK analysis, except this is not enough. Here is patch which survived netns start/stop/modprobe/rmmod cycles. Alexey, who still doesn't get why bug reproduces so easily for bug reporter. Luca, please confirm. Audit for the rest of the modules pending. [PATCH] af_key: fix netns ops ordering on module load/unload 1. After sock_register() returns, it's possible to create sockets, even if module still not initialized fully (blame generic module code for that!) 2. Consequently, pfkey_create() can be called with pfkey_net_id still not initialized which will BUG_ON in net_generic(): kernel BUG at include/net/netns/generic.h:43! 3. During netns shutdown, netns ops should be unregistered after key manager unregistered because key manager calls can be triggered from xfrm_user module: general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC pfkey_broadcast+0x111/0x210 [af_key] pfkey_send_notify+0x16a/0x300 [af_key] km_state_notify+0x41/0x70 xfrm_flush_sa+0x75/0x90 [xfrm_user] 4. Unregister netns ops after socket ops just in case and for symmetry. Reported by Luca Tettamanti. Signed-off-by: Alexey Dobriyan --- net/key/af_key.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) --- a/net/key/af_key.c +++ b/net/key/af_key.c @@ -3794,9 +3794,9 @@ static struct pernet_operations pfkey_net_ops = { static void __exit ipsec_pfkey_exit(void) { - unregister_pernet_subsys(&pfkey_net_ops); xfrm_unregister_km(&pfkeyv2_mgr); sock_unregister(PF_KEY); + unregister_pernet_subsys(&pfkey_net_ops); proto_unregister(&key_proto); } @@ -3807,21 +3807,22 @@ static int __init ipsec_pfkey_init(void) if (err != 0) goto out; - err = sock_register(&pfkey_family_ops); + err = register_pernet_subsys(&pfkey_net_ops); if (err != 0) goto out_unregister_key_proto; + err = sock_register(&pfkey_family_ops); + if (err != 0) + goto out_unregister_pernet; err = xfrm_register_km(&pfkeyv2_mgr); if (err != 0) goto out_sock_unregister; - err = register_pernet_subsys(&pfkey_net_ops); - if (err != 0) - goto out_xfrm_unregister_km; out: return err; -out_xfrm_unregister_km: - xfrm_unregister_km(&pfkeyv2_mgr); + out_sock_unregister: sock_unregister(PF_KEY); +out_unregister_pernet: + unregister_pernet_subsys(&pfkey_net_ops); out_unregister_key_proto: proto_unregister(&key_proto); goto out;