From b56f2d55c6c22b0c5774b3b22e336fb6cc5f4094 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Mon, 10 May 2010 18:47:57 +0200 Subject: netfilter: use rcu_dereference_protected() Restore the rcu_dereference() calls in conntrack/expectation notifier and logger registration/unregistration, but use the _protected variant, which will be required by the upcoming __rcu annotations. Based on patch by Eric Dumazet Signed-off-by: Patrick McHardy --- net/netfilter/nf_conntrack_ecache.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) (limited to 'net/netfilter/nf_conntrack_ecache.c') diff --git a/net/netfilter/nf_conntrack_ecache.c b/net/netfilter/nf_conntrack_ecache.c index a94ac3ad02cb..cdcc7649476b 100644 --- a/net/netfilter/nf_conntrack_ecache.c +++ b/net/netfilter/nf_conntrack_ecache.c @@ -82,9 +82,12 @@ EXPORT_SYMBOL_GPL(nf_ct_deliver_cached_events); int nf_conntrack_register_notifier(struct nf_ct_event_notifier *new) { int ret = 0; + struct nf_ct_event_notifier *notify; mutex_lock(&nf_ct_ecache_mutex); - if (nf_conntrack_event_cb != NULL) { + notify = rcu_dereference_protected(nf_conntrack_event_cb, + lockdep_is_held(&nf_ct_ecache_mutex)); + if (notify != NULL) { ret = -EBUSY; goto out_unlock; } @@ -100,8 +103,12 @@ EXPORT_SYMBOL_GPL(nf_conntrack_register_notifier); void nf_conntrack_unregister_notifier(struct nf_ct_event_notifier *new) { + struct nf_ct_event_notifier *notify; + mutex_lock(&nf_ct_ecache_mutex); - BUG_ON(nf_conntrack_event_cb != new); + notify = rcu_dereference_protected(nf_conntrack_event_cb, + lockdep_is_held(&nf_ct_ecache_mutex)); + BUG_ON(notify != new); rcu_assign_pointer(nf_conntrack_event_cb, NULL); mutex_unlock(&nf_ct_ecache_mutex); } @@ -110,9 +117,12 @@ EXPORT_SYMBOL_GPL(nf_conntrack_unregister_notifier); int nf_ct_expect_register_notifier(struct nf_exp_event_notifier *new) { int ret = 0; + struct nf_exp_event_notifier *notify; mutex_lock(&nf_ct_ecache_mutex); - if (nf_expect_event_cb != NULL) { + notify = rcu_dereference_protected(nf_expect_event_cb, + lockdep_is_held(&nf_ct_ecache_mutex)); + if (notify != NULL) { ret = -EBUSY; goto out_unlock; } @@ -128,8 +138,12 @@ EXPORT_SYMBOL_GPL(nf_ct_expect_register_notifier); void nf_ct_expect_unregister_notifier(struct nf_exp_event_notifier *new) { + struct nf_exp_event_notifier *notify; + mutex_lock(&nf_ct_ecache_mutex); - BUG_ON(nf_expect_event_cb != new); + notify = rcu_dereference_protected(nf_expect_event_cb, + lockdep_is_held(&nf_ct_ecache_mutex)); + BUG_ON(notify != new); rcu_assign_pointer(nf_expect_event_cb, NULL); mutex_unlock(&nf_ct_ecache_mutex); } -- cgit v1.2.3