From 94997e33907e55110fb08088860b2aff5c48b0f3 Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Tue, 16 Feb 2010 07:57:44 +0000 Subject: [PATCH] gre: fix netns vs proto registration ordering 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 --- net/ipv4/ip_gre.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 7631b20490f52..a2a5983dbf039 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_device(&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_device(&ipgre_net_ops); -gen_device_failed: inet_del_protocol(&ipgre_protocol, IPPROTO_GRE); +add_proto_failed: + unregister_pernet_device(&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_device(&ipgre_net_ops); if (inet_del_protocol(&ipgre_protocol, IPPROTO_GRE) < 0) printk(KERN_INFO "ipgre close: can't remove protocol\n"); + unregister_pernet_device(&ipgre_net_ops); } module_init(ipgre_init); -- 2.39.5