diff options
| author |   Florian Westphal <fw@strlen.de> | 2021-04-07 21:43:40 +0200 |
|---|---|---|
| committer |   Pablo Neira Ayuso <pablo@netfilter.org> | 2021-04-10 21:18:24 +0200 |
| commit | d163a925ebbc6eb5b562b0f1d72c7e817aa75c40 (patch) | |
| tree | e8cd49d2df51c8418824ec07a858953c783454a4 | |
| parent | netfilter: bridge: add pre_exit hooks for ebtable unregistration (diff) | |
| download | linux-dev-d163a925ebbc6eb5b562b0f1d72c7e817aa75c40.tar.xz linux-dev-d163a925ebbc6eb5b562b0f1d72c7e817aa75c40.zip | |
netfilter: arp_tables: add pre_exit hook for table unregister
Same problem that also existed in iptables/ip(6)tables, when
arptable_filter is removed there is no longer a wait period before the
table/ruleset is free'd.
Unregister the hook in pre_exit, then remove the table in the exit
function.
This used to work correctly because the old nf_hook_unregister API
did unconditional synchronize_net.
The per-net hook unregister function uses call_rcu instead.
Fixes: b9e69e127397 ("netfilter: xtables: don't hook tables by default")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | include/linux/netfilter_arp/arp_tables.h | 5 | ||||
| -rw-r--r-- | net/ipv4/netfilter/arp_tables.c | 9 | ||||
| -rw-r--r-- | net/ipv4/netfilter/arptable_filter.c | 10 |
3 files changed, 19 insertions, 5 deletions
diff --git a/include/linux/netfilter_arp/arp_tables.h b/include/linux/netfilter_arp/arp_tables.h index 7d3537c40ec9..26a13294318c 100644 --- a/include/linux/netfilter_arp/arp_tables.h +++ b/include/linux/netfilter_arp/arp_tables.h @@ -52,8 +52,9 @@ extern void *arpt_alloc_initial_table(const struct xt_table *); int arpt_register_table(struct net *net, const struct xt_table *table, const struct arpt_replace *repl, const struct nf_hook_ops *ops, struct xt_table **res); -void arpt_unregister_table(struct net *net, struct xt_table *table, - const struct nf_hook_ops *ops); +void arpt_unregister_table(struct net *net, struct xt_table *table); +void arpt_unregister_table_pre_exit(struct net *net, struct xt_table *table, + const struct nf_hook_ops *ops); extern unsigned int arpt_do_table(struct sk_buff *skb, const struct nf_hook_state *state, struct xt_table *table); diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index d1e04d2b5170..6c26533480dd 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -1539,10 +1539,15 @@ out_free: return ret; } -void arpt_unregister_table(struct net *net, struct xt_table *table, - const struct nf_hook_ops *ops) +void arpt_unregister_table_pre_exit(struct net *net, struct xt_table *table, + const struct nf_hook_ops *ops) { nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks)); +} +EXPORT_SYMBOL(arpt_unregister_table_pre_exit); + +void arpt_unregister_table(struct net *net, struct xt_table *table) +{ __arpt_unregister_table(net, table); } diff --git a/net/ipv4/netfilter/arptable_filter.c b/net/ipv4/netfilter/arptable_filter.c index c216b9ad3bb2..6c300ba5634e 100644 --- a/net/ipv4/netfilter/arptable_filter.c +++ b/net/ipv4/netfilter/arptable_filter.c @@ -56,16 +56,24 @@ static int __net_init arptable_filter_table_init(struct net *net) return err; } +static void __net_exit arptable_filter_net_pre_exit(struct net *net) +{ + if (net->ipv4.arptable_filter) + arpt_unregister_table_pre_exit(net, net->ipv4.arptable_filter, + arpfilter_ops); +} + static void __net_exit arptable_filter_net_exit(struct net *net) { if (!net->ipv4.arptable_filter) return; - arpt_unregister_table(net, net->ipv4.arptable_filter, arpfilter_ops); + arpt_unregister_table(net, net->ipv4.arptable_filter); net->ipv4.arptable_filter = NULL; } static struct pernet_operations arptable_filter_net_ops = { .exit = arptable_filter_net_exit, + .pre_exit = arptable_filter_net_pre_exit, }; static int __init arptable_filter_init(void) |