From b3afdc17586392e023ac57155970269d03d4e886 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 16 Aug 2021 17:16:24 +0200 Subject: [PATCH] netfilter: ecache: add common helper for nf_conntrack_eventmask_report nf_ct_deliver_cached_events and nf_conntrack_eventmask_report are very similar. Split nf_conntrack_eventmask_report into a common helper function that can be used for both cases. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_ecache.c | 124 ++++++++++++++++-------------------- 1 file changed, 56 insertions(+), 68 deletions(-) diff --git a/net/netfilter/nf_conntrack_ecache.c b/net/netfilter/nf_conntrack_ecache.c index 127a0fa..fbe04e1 100644 --- a/net/netfilter/nf_conntrack_ecache.c +++ b/net/netfilter/nf_conntrack_ecache.c @@ -130,27 +130,57 @@ static void ecache_work(struct work_struct *work) schedule_delayed_work(&cnet->ecache_dwork, delay); } -int nf_conntrack_eventmask_report(unsigned int eventmask, struct nf_conn *ct, - u32 portid, int report) +static int __nf_conntrack_eventmask_report(struct nf_conntrack_ecache *e, + const unsigned int events, + const unsigned long missed, + const struct nf_ct_event *item) { - struct net *net = nf_ct_net(ct); + struct nf_conn *ct = item->ct; + struct net *net = nf_ct_net(item->ct); struct nf_ct_event_notifier *notify; + int ret; + + if (!((events | missed) & e->ctmask)) + return 0; + + rcu_read_lock(); + + notify = rcu_dereference(net->ct.nf_conntrack_event_cb); + if (!notify) { + rcu_read_unlock(); + return 0; + } + + ret = notify->fcn(events | missed, item); + rcu_read_unlock(); + + if (likely(ret >= 0 && missed == 0)) + return 0; + + spin_lock_bh(&ct->lock); + if (ret < 0) + e->missed |= events; + else + e->missed &= ~missed; + spin_unlock_bh(&ct->lock); + + return ret; +} + +int nf_conntrack_eventmask_report(unsigned int events, struct nf_conn *ct, + u32 portid, int report) +{ struct nf_conntrack_ecache *e; struct nf_ct_event item; unsigned long missed; - int ret = 0; + int ret; if (!nf_ct_is_confirmed(ct)) - return ret; - - rcu_read_lock(); - notify = rcu_dereference(net->ct.nf_conntrack_event_cb); - if (!notify) - goto out_unlock; + return 0; e = nf_ct_ecache_find(ct); if (!e) - goto out_unlock; + return 0; memset(&item, 0, sizeof(item)); @@ -161,33 +191,16 @@ int nf_conntrack_eventmask_report(unsigned int eventmask, struct nf_conn *ct, /* This is a resent of a destroy event? If so, skip missed */ missed = e->portid ? 0 : e->missed; - if (!((eventmask | missed) & e->ctmask)) - goto out_unlock; - - ret = notify->fcn(eventmask | missed, &item); - if (likely(ret >= 0 && !missed)) - goto out_unlock; - - spin_lock_bh(&ct->lock); - if (ret < 0) { - /* This is a destroy event that has been - * triggered by a process, we store the PORTID - * to include it in the retransmission. + ret = __nf_conntrack_eventmask_report(e, events, missed, &item); + if (unlikely(ret < 0 && (events & (1 << IPCT_DESTROY)))) { + /* This is a destroy event that has been triggered by a process, + * we store the PORTID to include it in the retransmission. */ - if (eventmask & (1 << IPCT_DESTROY)) { - if (e->portid == 0 && portid != 0) - e->portid = portid; - e->state = NFCT_ECACHE_DESTROY_FAIL; - } else { - e->missed |= eventmask; - } - } else { - e->missed &= ~missed; + if (e->portid == 0 && portid != 0) + e->portid = portid; + e->state = NFCT_ECACHE_DESTROY_FAIL; } - spin_unlock_bh(&ct->lock); -out_unlock: - rcu_read_unlock(); return ret; } EXPORT_SYMBOL_GPL(nf_conntrack_eventmask_report); @@ -196,53 +209,28 @@ EXPORT_SYMBOL_GPL(nf_conntrack_eventmask_report); * disabled softirqs */ void nf_ct_deliver_cached_events(struct nf_conn *ct) { - struct net *net = nf_ct_net(ct); - unsigned long events, missed; - struct nf_ct_event_notifier *notify; struct nf_conntrack_ecache *e; struct nf_ct_event item; - int ret; - - rcu_read_lock(); - notify = rcu_dereference(net->ct.nf_conntrack_event_cb); - if (notify == NULL) - goto out_unlock; + unsigned long events; if (!nf_ct_is_confirmed(ct) || nf_ct_is_dying(ct)) - goto out_unlock; + return; e = nf_ct_ecache_find(ct); if (e == NULL) - goto out_unlock; + return; events = xchg(&e->cache, 0); - /* We make a copy of the missed event cache without taking - * the lock, thus we may send missed events twice. However, - * this does not harm and it happens very rarely. */ - missed = e->missed; - - if (!((events | missed) & e->ctmask)) - goto out_unlock; - item.ct = ct; item.portid = 0; item.report = 0; - ret = notify->fcn(events | missed, &item); - - if (likely(ret == 0 && !missed)) - goto out_unlock; - - spin_lock_bh(&ct->lock); - if (ret < 0) - e->missed |= events; - else - e->missed &= ~missed; - spin_unlock_bh(&ct->lock); - -out_unlock: - rcu_read_unlock(); + /* We make a copy of the missed event cache without taking + * the lock, thus we may send missed events twice. However, + * this does not harm and it happens very rarely. + */ + __nf_conntrack_eventmask_report(e, events, e->missed, &item); } EXPORT_SYMBOL_GPL(nf_ct_deliver_cached_events); -- 2.7.4