diff options
| author |   Florian Westphal <fw@strlen.de> | 2020-08-26 00:52:45 +0200 |
|---|---|---|
| committer |   Pablo Neira Ayuso <pablo@netfilter.org> | 2020-08-28 19:51:27 +0200 |
| commit | ff73e7479b8eea594a985ca29f4b45d604dbcb2c (patch) | |
| tree | 8f68c885e6451f2343317f853cdb13da83d5ee82 /net/netfilter/nf_conntrack_core.c | |
| parent | netfilter: conntrack: add clash resolution stat counter (diff) | |
| download | linux-dev-ff73e7479b8eea594a985ca29f4b45d604dbcb2c.tar.xz linux-dev-ff73e7479b8eea594a985ca29f4b45d604dbcb2c.zip | |
netfilter: conntrack: remove unneeded nf_ct_put
We can delay refcount increment until we reassign the existing entry to
the current skb.
A 0 refcount can't happen while the nf_conn object is still in the
hash table and parallel mutations are impossible because we hold the
bucket lock.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter/nf_conntrack_core.c')
| -rw-r--r-- | net/netfilter/nf_conntrack_core.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 93e77ca0efad..234b7cab37c3 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -908,6 +908,7 @@ static void __nf_conntrack_insert_prepare(struct nf_conn *ct) tstamp->start = ktime_get_real_ns(); } +/* caller must hold locks to prevent concurrent changes */ static int __nf_ct_resolve_clash(struct sk_buff *skb, struct nf_conntrack_tuple_hash *h) { @@ -921,13 +922,12 @@ static int __nf_ct_resolve_clash(struct sk_buff *skb, if (nf_ct_is_dying(ct)) return NF_DROP; - if (!atomic_inc_not_zero(&ct->ct_general.use)) - return NF_DROP; - if (((ct->status & IPS_NAT_DONE_MASK) == 0) || nf_ct_match(ct, loser_ct)) { struct net *net = nf_ct_net(ct); + nf_conntrack_get(&ct->ct_general); + nf_ct_acct_merge(ct, ctinfo, loser_ct); nf_ct_add_to_dying_list(loser_ct); nf_conntrack_put(&loser_ct->ct_general); @@ -937,7 +937,6 @@ static int __nf_ct_resolve_clash(struct sk_buff *skb, return NF_ACCEPT; } - nf_ct_put(ct); return NF_DROP; } |