From 83731671d9e6878c0a05d309c68fb71c16d3235a Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 6 Apr 2009 17:47:20 +0200 Subject: [PATCH] netfilter: ctnetlink: fix regression in expectation handling This patch fixes a regression (introduced by myself in commit 19abb7b: netfilter: ctnetlink: deliver events for conntracks changed from userspace) that results in an expectation re-insertion since __nf_ct_expect_check() may return 0 for expectation timer refreshing. This patch also removes a unnecessary refcount bump that pretended to avoid a possible race condition with event delivery and expectation timers (as said, not needed since we hold a reference to the object since until we finish the expectation setup). This also merges nf_ct_expect_related_report() and nf_ct_expect_related() which look basically the same. Reported-by: Patrick McHardy Signed-off-by: Pablo Neira Ayuso Signed-off-by: Patrick McHardy --- include/net/netfilter/nf_conntrack_expect.h | 5 ++++- net/netfilter/nf_conntrack_expect.c | 30 ++++++----------------------- 2 files changed, 10 insertions(+), 25 deletions(-) diff --git a/include/net/netfilter/nf_conntrack_expect.h b/include/net/netfilter/nf_conntrack_expect.h index ab17a15..a965280 100644 --- a/include/net/netfilter/nf_conntrack_expect.h +++ b/include/net/netfilter/nf_conntrack_expect.h @@ -99,9 +99,12 @@ void nf_ct_expect_init(struct nf_conntrack_expect *, unsigned int, u_int8_t, const union nf_inet_addr *, u_int8_t, const __be16 *, const __be16 *); void nf_ct_expect_put(struct nf_conntrack_expect *exp); -int nf_ct_expect_related(struct nf_conntrack_expect *expect); int nf_ct_expect_related_report(struct nf_conntrack_expect *expect, u32 pid, int report); +static inline int nf_ct_expect_related(struct nf_conntrack_expect *expect) +{ + return nf_ct_expect_related_report(expect, 0, 0); +} #endif /*_NF_CONNTRACK_EXPECT_H*/ diff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c index 3940f99..afde8f9 100644 --- a/net/netfilter/nf_conntrack_expect.c +++ b/net/netfilter/nf_conntrack_expect.c @@ -372,7 +372,7 @@ static inline int __nf_ct_expect_check(struct nf_conntrack_expect *expect) struct net *net = nf_ct_exp_net(expect); struct hlist_node *n; unsigned int h; - int ret = 0; + int ret = 1; if (!master_help->helper) { ret = -ESHUTDOWN; @@ -412,41 +412,23 @@ out: return ret; } -int nf_ct_expect_related(struct nf_conntrack_expect *expect) +int nf_ct_expect_related_report(struct nf_conntrack_expect *expect, + u32 pid, int report) { int ret; spin_lock_bh(&nf_conntrack_lock); ret = __nf_ct_expect_check(expect); - if (ret < 0) + if (ret <= 0) goto out; + ret = 0; nf_ct_expect_insert(expect); - atomic_inc(&expect->use); - spin_unlock_bh(&nf_conntrack_lock); - nf_ct_expect_event(IPEXP_NEW, expect); - nf_ct_expect_put(expect); - return ret; -out: spin_unlock_bh(&nf_conntrack_lock); + nf_ct_expect_event_report(IPEXP_NEW, expect, pid, report); return ret; -} -EXPORT_SYMBOL_GPL(nf_ct_expect_related); - -int nf_ct_expect_related_report(struct nf_conntrack_expect *expect, - u32 pid, int report) -{ - int ret; - - spin_lock_bh(&nf_conntrack_lock); - ret = __nf_ct_expect_check(expect); - if (ret < 0) - goto out; - nf_ct_expect_insert(expect); out: spin_unlock_bh(&nf_conntrack_lock); - if (ret == 0) - nf_ct_expect_event_report(IPEXP_NEW, expect, pid, report); return ret; } EXPORT_SYMBOL_GPL(nf_ct_expect_related_report); -- 1.8.2.3