4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Mahesh Bandewar <maheshb@xxxxxxxxxx>
[ Upstream commit 8799a221f5944a7d74516ecf46d58c28ec1d1f75 ]
Net stack initialization currently initializes fib-trie after the
first call to netdevice_notifier() call. In fact fib_trie initialization
needs to happen before first rtnl_register(). It does not cause any problem
since there are no devices UP at this moment, but trying to bring 'lo'
UP at initialization would make this assumption wrong and exposes the issue.
Fixes following crash
Call Trace:
? alternate_node_alloc+0x76/0xa0
fib_table_insert+0x1b7/0x4b0
fib_magic.isra.17+0xea/0x120
fib_add_ifaddr+0x7b/0x190
fib_netdev_event+0xc0/0x130
register_netdevice_notifier+0x1c1/0x1d0
ip_fib_init+0x72/0x85
ip_rt_init+0x187/0x1e9
ip_init+0xe/0x1a
inet_init+0x171/0x26c
? ipv4_offload_init+0x66/0x66
do_one_initcall+0x43/0x160
kernel_init_freeable+0x191/0x219
? rest_init+0x80/0x80
kernel_init+0xe/0x150
ret_from_fork+0x22/0x30
Code: f6 46 23 04 74 86 4c 89 f7 e8 ae 45 01 00 49 89 c7 4d 85 ff 0f 85 7b ff ff ff 31 db eb 08 4c 89 ff e8 16 47 01 00 48 8b 44 24 38 <45> 8b 6e 14 4d 63 76 74 48 89 04 24 0f 1f 44 00 00 48 83 c4 08
RIP: kmem_cache_alloc+0xcf/0x1c0 RSP: ffff9b1500017c28
CR2: 0000000000000014
Fixes: 7b1a74fdbb9e ("[NETNS]: Refactor fib initialization so it can handle multiple namespaces.")
Fixes: 7f9b80529b8a ("[IPV4]: fib hash|trie initialization")
Signed-off-by: Mahesh Bandewar <maheshb@xxxxxxxxxx>
Acked-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv4/fib_frontend.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -1319,13 +1319,14 @@ static struct pernet_operations fib_net_
void __init ip_fib_init(void)
{
- rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, NULL);
- rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, NULL);
- rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, NULL);
+ fib_trie_init();
register_pernet_subsys(&fib_net_ops);
+
register_netdevice_notifier(&fib_netdev_notifier);
register_inetaddr_notifier(&fib_inetaddr_notifier);
- fib_trie_init();
+ rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, NULL);
+ rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, NULL);
+ rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, NULL);
}