diff options
author | Patrick McHardy <kaber@trash.net> | 2010-04-09 16:42:15 +0200 |
---|---|---|
committer | Patrick McHardy <kaber@trash.net> | 2010-04-09 16:42:15 +0200 |
commit | ed86308f6179d8fa6151c2d0f652aad0091548e2 (patch) | |
tree | 7a85671939266d2f80a03395f4c8af6f15f93948 /net/netfilter/nf_conntrack_ecache.c | |
parent | e9f13cab49f7f28b65a6f63201fca56480b2e059 (diff) |
netfilter: remove invalid rcu_dereference() calls
The CONFIG_PROVE_RCU option discovered a few invalid uses of
rcu_dereference() in netfilter. In all these cases, the code code
intends to check whether a pointer is already assigned when
performing registration or whether the assigned pointer matches
when performing unregistration. The entire registration/
unregistration is protected by a mutex, so we don't need the
rcu_dereference() calls.
Reported-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Tested-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Diffstat (limited to 'net/netfilter/nf_conntrack_ecache.c')
-rw-r--r-- | net/netfilter/nf_conntrack_ecache.c | 18 |
1 files changed, 4 insertions, 14 deletions
diff --git a/net/netfilter/nf_conntrack_ecache.c b/net/netfilter/nf_conntrack_ecache.c index d5a9bcd7d61b..849614af2322 100644 --- a/net/netfilter/nf_conntrack_ecache.c +++ b/net/netfilter/nf_conntrack_ecache.c @@ -81,11 +81,9 @@ 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); - notify = rcu_dereference(nf_conntrack_event_cb); - if (notify != NULL) { + if (nf_conntrack_event_cb != NULL) { ret = -EBUSY; goto out_unlock; } @@ -101,11 +99,8 @@ 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); - notify = rcu_dereference(nf_conntrack_event_cb); - BUG_ON(notify != new); + BUG_ON(nf_conntrack_event_cb != new); rcu_assign_pointer(nf_conntrack_event_cb, NULL); mutex_unlock(&nf_ct_ecache_mutex); } @@ -114,11 +109,9 @@ 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); - notify = rcu_dereference(nf_expect_event_cb); - if (notify != NULL) { + if (nf_expect_event_cb != NULL) { ret = -EBUSY; goto out_unlock; } @@ -134,11 +127,8 @@ 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); - notify = rcu_dereference(nf_expect_event_cb); - BUG_ON(notify != new); + BUG_ON(nf_expect_event_cb != new); rcu_assign_pointer(nf_expect_event_cb, NULL); mutex_unlock(&nf_ct_ecache_mutex); } |