From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
canqun zhang reported that we're hitting BUG_ON in the
nf_conntrack_destroy path when calling kfree_skb while
rmmod'ing the nf_conntrack module.
Currently, the nf_ct_destroy hook is being set to NULL in the
destroy path of conntrack.init_net. However, this is a problem
since init_net may be destroyed before any other existing netns
(we cannot assume any specific ordering while releasing existing
netns according to what I read in recent emails).
Thanks to Gao feng for initial patch to address this issue.
Reported-by: canqun zhang <canqunzhang@xxxxxxxxx>
Acked-by: Gao feng <gaofeng@xxxxxxxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
include/net/netfilter/nf_conntrack_core.h | 2 ++
net/netfilter/nf_conntrack_core.c | 9 +++++----
net/netfilter/nf_conntrack_standalone.c | 1 +
3 files changed, 8 insertions(+), 4 deletions(-)
diff --git a/include/net/netfilter/nf_conntrack_core.h b/include/net/netfilter/nf_conntrack_core.h
index d8f5b9f..e98aeb3 100644
--- a/include/net/netfilter/nf_conntrack_core.h
+++ b/include/net/netfilter/nf_conntrack_core.h
@@ -31,6 +31,8 @@ extern void nf_conntrack_cleanup(struct net *net);
extern int nf_conntrack_proto_init(struct net *net);
extern void nf_conntrack_proto_fini(struct net *net);
+extern void nf_conntrack_cleanup_end(void);
+
extern bool
nf_ct_get_tuple(const struct sk_buff *skb,
unsigned int nhoff,
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index 0f241be..ec02168 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -1383,11 +1383,12 @@ void nf_conntrack_cleanup(struct net *net)
synchronize_net();
nf_conntrack_proto_fini(net);
nf_conntrack_cleanup_net(net);
+}
- if (net_eq(net, &init_net)) {
- RCU_INIT_POINTER(nf_ct_destroy, NULL);
- nf_conntrack_cleanup_init_net();
- }
+void nf_conntrack_cleanup_end(void)
+{
+ RCU_INIT_POINTER(nf_ct_destroy, NULL);
+ nf_conntrack_cleanup_init_net();
}
void *nf_ct_alloc_hashtable(unsigned int *sizep, int nulls)
diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index 9b39432..df8aa3a 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -571,6 +571,7 @@ static int __init nf_conntrack_standalone_init(void)
static void __exit nf_conntrack_standalone_fini(void)
{
unregister_pernet_subsys(&nf_conntrack_net_ops);
+ nf_conntrack_cleanup_end();
}
module_init(nf_conntrack_standalone_init);
--
1.7.10.4
--
To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
