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author | Francesco Ruggeri <fruggeri@aristanetworks.com> | 2015-05-17 14:30:31 -0700 |
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committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2015-05-20 13:46:48 +0200 |
commit | 3bfe049807c240344b407e3cfb74544927359817 (patch) | |
tree | 22abdea7b3d64fbf55a028afc0066ddc9ca40235 /net/netfilter/nfnetlink_log.c | |
parent | 13c3ed6a92724d8c8cb148a14b0ae190ddfe7413 (diff) | |
download | talos-op-linux-3bfe049807c240344b407e3cfb74544927359817.tar.gz talos-op-linux-3bfe049807c240344b407e3cfb74544927359817.zip |
netfilter: nfnetlink_{log,queue}: Register pernet in first place
nfnetlink_{log,queue}_init() register the netlink callback nf*_rcv_nl_event
before registering the pernet_subsys, but the callback relies on data
structures allocated by pernet init functions.
When nfnetlink_{log,queue} is loaded, if a netlink message is received after
the netlink callback is registered but before the pernet_subsys is registered,
the kernel will panic in the sequence
nfulnl_rcv_nl_event
nfnl_log_pernet
net_generic
BUG_ON(id == 0) where id is nfnl_log_net_id.
The panic can be easily reproduced in 4.0.3 by:
while true ;do modprobe nfnetlink_log ; rmmod nfnetlink_log ; done &
while true ;do ip netns add dummy ; ip netns del dummy ; done &
This patch moves register_pernet_subsys to earlier in nfnetlink_log_init.
Notice that the BUG_ON hit in 4.0.3 was recently removed in 2591ffd308
["netns: remove BUG_ONs from net_generic()"].
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter/nfnetlink_log.c')
-rw-r--r-- | net/netfilter/nfnetlink_log.c | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c index 3ad91266c821..4ef1fae8445e 100644 --- a/net/netfilter/nfnetlink_log.c +++ b/net/netfilter/nfnetlink_log.c @@ -1073,7 +1073,13 @@ static struct pernet_operations nfnl_log_net_ops = { static int __init nfnetlink_log_init(void) { - int status = -ENOMEM; + int status; + + status = register_pernet_subsys(&nfnl_log_net_ops); + if (status < 0) { + pr_err("failed to register pernet ops\n"); + goto out; + } netlink_register_notifier(&nfulnl_rtnl_notifier); status = nfnetlink_subsys_register(&nfulnl_subsys); @@ -1088,28 +1094,23 @@ static int __init nfnetlink_log_init(void) goto cleanup_subsys; } - status = register_pernet_subsys(&nfnl_log_net_ops); - if (status < 0) { - pr_err("failed to register pernet ops\n"); - goto cleanup_logger; - } return status; -cleanup_logger: - nf_log_unregister(&nfulnl_logger); cleanup_subsys: nfnetlink_subsys_unregister(&nfulnl_subsys); cleanup_netlink_notifier: netlink_unregister_notifier(&nfulnl_rtnl_notifier); + unregister_pernet_subsys(&nfnl_log_net_ops); +out: return status; } static void __exit nfnetlink_log_fini(void) { - unregister_pernet_subsys(&nfnl_log_net_ops); nf_log_unregister(&nfulnl_logger); nfnetlink_subsys_unregister(&nfulnl_subsys); netlink_unregister_notifier(&nfulnl_rtnl_notifier); + unregister_pernet_subsys(&nfnl_log_net_ops); } MODULE_DESCRIPTION("netfilter userspace logging"); |