aboutsummaryrefslogtreecommitdiff
path: root/net/netfilter/nf_conntrack_core.c
diff options
context:
space:
mode:
authorPablo Neira Ayuso <pablo@netfilter.org>2012-08-29 16:25:49 +0000
committerPablo Neira Ayuso <pablo@netfilter.org>2012-08-31 15:50:28 +0200
commit5b423f6a40a0327f9d40bc8b97ce9be266f74368 (patch)
treef71b7726f6501993bc7be9d4d7e6e69d7cd095b2 /net/netfilter/nf_conntrack_core.c
parent3f509c689a07a4aa989b426893d8491a7ffcc410 (diff)
downloadlinux-stericsson-5b423f6a40a0327f9d40bc8b97ce9be266f74368.tar.gz
netfilter: nf_conntrack: fix racy timer handling with reliable events
Existing code assumes that del_timer returns true for alive conntrack entries. However, this is not true if reliable events are enabled. In that case, del_timer may return true for entries that were just inserted in the dying list. Note that packets / ctnetlink may hold references to conntrack entries that were just inserted to such list. This patch fixes the issue by adding an independent timer for event delivery. This increases the size of the ecache extension. Still we can revisit this later and use variable size extensions to allocate this area on demand. Tested-by: Oliver Smith <olipro@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa> 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.c16
1 files changed, 11 insertions, 5 deletions
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index cf4875565d67..2ceec64b19f9 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -249,12 +249,15 @@ static void death_by_event(unsigned long ul_conntrack)
{
struct nf_conn *ct = (void *)ul_conntrack;
struct net *net = nf_ct_net(ct);
+ struct nf_conntrack_ecache *ecache = nf_ct_ecache_find(ct);
+
+ BUG_ON(ecache == NULL);
if (nf_conntrack_event(IPCT_DESTROY, ct) < 0) {
/* bad luck, let's retry again */
- ct->timeout.expires = jiffies +
+ ecache->timeout.expires = jiffies +
(random32() % net->ct.sysctl_events_retry_timeout);
- add_timer(&ct->timeout);
+ add_timer(&ecache->timeout);
return;
}
/* we've got the event delivered, now it's dying */
@@ -268,6 +271,9 @@ static void death_by_event(unsigned long ul_conntrack)
void nf_ct_insert_dying_list(struct nf_conn *ct)
{
struct net *net = nf_ct_net(ct);
+ struct nf_conntrack_ecache *ecache = nf_ct_ecache_find(ct);
+
+ BUG_ON(ecache == NULL);
/* add this conntrack to the dying list */
spin_lock_bh(&nf_conntrack_lock);
@@ -275,10 +281,10 @@ void nf_ct_insert_dying_list(struct nf_conn *ct)
&net->ct.dying);
spin_unlock_bh(&nf_conntrack_lock);
/* set a new timer to retry event delivery */
- setup_timer(&ct->timeout, death_by_event, (unsigned long)ct);
- ct->timeout.expires = jiffies +
+ setup_timer(&ecache->timeout, death_by_event, (unsigned long)ct);
+ ecache->timeout.expires = jiffies +
(random32() % net->ct.sysctl_events_retry_timeout);
- add_timer(&ct->timeout);
+ add_timer(&ecache->timeout);
}
EXPORT_SYMBOL_GPL(nf_ct_insert_dying_list);