From 7606088a8d06062750d6d24cab6e064d7711356e Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Tue, 16 Feb 2010 07:57:44 +0000 Subject: gre: fix netns vs proto registration ordering commit c2892f02712e9516d72841d5c019ed6916329794 upstream. GRE protocol receive hook can be called right after protocol addition is done. If netns stuff is not yet initialized, we're going to oops in net_generic(). This is remotely oopsable if ip_gre is compiled as module and packet comes at unfortunate moment of module loading. Signed-off-by: Alexey Dobriyan Signed-off-by: David S. Miller [dannf: backported to Debian's 2.6.32] Signed-off-by: Greg Kroah-Hartman --- net/ipv4/ip_gre.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) (limited to 'net') diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index cfab9e419ef3..f6145847186a 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -1665,14 +1665,15 @@ static int __init ipgre_init(void) printk(KERN_INFO "GRE over IPv4 tunneling driver\n"); - if (inet_add_protocol(&ipgre_protocol, IPPROTO_GRE) < 0) { - printk(KERN_INFO "ipgre init: can't add protocol\n"); - return -EAGAIN; - } - err = register_pernet_gen_device(&ipgre_net_id, &ipgre_net_ops); if (err < 0) - goto gen_device_failed; + return err; + + err = inet_add_protocol(&ipgre_protocol, IPPROTO_GRE); + if (err < 0) { + printk(KERN_INFO "ipgre init: can't add protocol\n"); + goto add_proto_failed; + } err = rtnl_link_register(&ipgre_link_ops); if (err < 0) @@ -1688,9 +1689,9 @@ out: tap_ops_failed: rtnl_link_unregister(&ipgre_link_ops); rtnl_link_failed: - unregister_pernet_gen_device(ipgre_net_id, &ipgre_net_ops); -gen_device_failed: inet_del_protocol(&ipgre_protocol, IPPROTO_GRE); +add_proto_failed: + unregister_pernet_gen_device(ipgre_net_id, &ipgre_net_ops); goto out; } @@ -1698,9 +1699,9 @@ static void __exit ipgre_fini(void) { rtnl_link_unregister(&ipgre_tap_ops); rtnl_link_unregister(&ipgre_link_ops); - unregister_pernet_gen_device(ipgre_net_id, &ipgre_net_ops); if (inet_del_protocol(&ipgre_protocol, IPPROTO_GRE) < 0) printk(KERN_INFO "ipgre close: can't remove protocol\n"); + unregister_pernet_gen_device(ipgre_net_id, &ipgre_net_ops); } module_init(ipgre_init); -- cgit v1.2.3