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author | Taehee Yoo <ap420073@gmail.com> | 2017-07-19 14:27:33 +0900 |
---|---|---|
committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2017-07-24 13:24:46 +0200 |
commit | 0b35f6031a00329800bacc04085188c300c3a4d8 (patch) | |
tree | b4e34d6ab10b8b065583f1ce7c75ec05dea5a107 /net/netfilter/nf_conntrack_netlink.c | |
parent | 9f08ea848117ab521efcfd3e004d8e1a0edc640c (diff) | |
download | op-kernel-dev-0b35f6031a00329800bacc04085188c300c3a4d8.zip op-kernel-dev-0b35f6031a00329800bacc04085188c300c3a4d8.tar.gz |
netfilter: Remove duplicated rcu_read_lock.
This patch removes duplicate rcu_read_lock().
1. IPVS part:
According to Julian Anastasov's mention, contexts of ipvs are described
at: http://marc.info/?l=netfilter-devel&m=149562884514072&w=2, in summary:
- packet RX/TX: does not need locks because packets come from hooks.
- sync msg RX: backup server uses RCU locks while registering new
connections.
- ip_vs_ctl.c: configuration get/set, RCU locks needed.
- xt_ipvs.c: It is a netfilter match, running from hook context.
As result, rcu_read_lock and rcu_read_unlock can be removed from:
- ip_vs_core.c: all
- ip_vs_ctl.c:
- only from ip_vs_has_real_service
- ip_vs_ftp.c: all
- ip_vs_proto_sctp.c: all
- ip_vs_proto_tcp.c: all
- ip_vs_proto_udp.c: all
- ip_vs_xmit.c: all (contains only packet processing)
2. Netfilter part:
There are three types of functions that are guaranteed the rcu_read_lock().
First, as result, functions are only called by nf_hook():
- nf_conntrack_broadcast_help(), pptp_expectfn(), set_expected_rtp_rtcp().
- tcpmss_reverse_mtu(), tproxy_laddr4(), tproxy_laddr6().
- match_lookup_rt6(), check_hlist(), hashlimit_mt_common().
- xt_osf_match_packet().
Second, functions that caller already held the rcu_read_lock().
- destroy_conntrack(), ctnetlink_conntrack_event().
- ctnl_timeout_find_get(), nfqnl_nf_hook_drop().
Third, functions that are mixed with type1 and type2.
These functions are called by nf_hook() also these are called by
ordinary functions that already held the rcu_read_lock():
- __ctnetlink_glue_build(), ctnetlink_expect_event().
- ctnetlink_proto_size().
Applied files are below:
- nf_conntrack_broadcast.c, nf_conntrack_core.c, nf_conntrack_netlink.c.
- nf_conntrack_pptp.c, nf_conntrack_sip.c, nfnetlink_cttimeout.c.
- nfnetlink_queue.c, xt_TCPMSS.c, xt_TPROXY.c, xt_addrtype.c.
- xt_connlimit.c, xt_hashlimit.c, xt_osf.c
Detailed calltrace can be found at:
http://marc.info/?l=netfilter-devel&m=149667610710350&w=2
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter/nf_conntrack_netlink.c')
-rw-r--r-- | net/netfilter/nf_conntrack_netlink.c | 12 |
1 files changed, 0 insertions, 12 deletions
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 7999e70..4dba71d 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -539,13 +539,11 @@ static inline size_t ctnetlink_proto_size(const struct nf_conn *ct) struct nf_conntrack_l4proto *l4proto; size_t len = 0; - rcu_read_lock(); l3proto = __nf_ct_l3proto_find(nf_ct_l3num(ct)); len += l3proto->nla_size; l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct)); len += l4proto->nla_size; - rcu_read_unlock(); return len; } @@ -664,7 +662,6 @@ ctnetlink_conntrack_event(unsigned int events, struct nf_ct_event *item) nfmsg->version = NFNETLINK_V0; nfmsg->res_id = 0; - rcu_read_lock(); zone = nf_ct_zone(ct); nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED); @@ -736,8 +733,6 @@ ctnetlink_conntrack_event(unsigned int events, struct nf_ct_event *item) && ctnetlink_dump_mark(skb, ct) < 0) goto nla_put_failure; #endif - rcu_read_unlock(); - nlmsg_end(skb, nlh); err = nfnetlink_send(skb, net, item->portid, group, item->report, GFP_ATOMIC); @@ -747,7 +742,6 @@ ctnetlink_conntrack_event(unsigned int events, struct nf_ct_event *item) return 0; nla_put_failure: - rcu_read_unlock(); nlmsg_cancel(skb, nlh); nlmsg_failure: kfree_skb(skb); @@ -2213,7 +2207,6 @@ static int __ctnetlink_glue_build(struct sk_buff *skb, struct nf_conn *ct) const struct nf_conntrack_zone *zone; struct nlattr *nest_parms; - rcu_read_lock(); zone = nf_ct_zone(ct); nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED); @@ -2272,11 +2265,9 @@ static int __ctnetlink_glue_build(struct sk_buff *skb, struct nf_conn *ct) #endif if (ctnetlink_dump_labels(skb, ct) < 0) goto nla_put_failure; - rcu_read_unlock(); return 0; nla_put_failure: - rcu_read_unlock(); return -ENOSPC; } @@ -2661,17 +2652,14 @@ ctnetlink_expect_event(unsigned int events, struct nf_exp_event *item) nfmsg->version = NFNETLINK_V0; nfmsg->res_id = 0; - rcu_read_lock(); if (ctnetlink_exp_dump_expect(skb, exp) < 0) goto nla_put_failure; - rcu_read_unlock(); nlmsg_end(skb, nlh); nfnetlink_send(skb, net, item->portid, group, item->report, GFP_ATOMIC); return 0; nla_put_failure: - rcu_read_unlock(); nlmsg_cancel(skb, nlh); nlmsg_failure: kfree_skb(skb); |