We must first remove the nfnetlink protocol handler when nf_tables module
is unloaded -- we don't want userspace to submit new change requests once
we've started to tear down nft state.
Furthermore, nfnetlink must not call any subsystem function after
call_batch returned -EAGAIN.
EAGAIN means the subsys mutex was dropped, so its unlikely but possible that
nf_tables subsystem was removed due to 'rmmod nf_tables' on another cpu.
Therefore, we must abort batch completely and not move on to next part of
the batch.
Last, we can't invoke ->abort unless we've checked that the subsystem is
still registered.
Change netns exit path of nf_tables to make sure any incompleted
transaction gets removed on exit.
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
---
net/netfilter/nf_tables_api.c | 12 +++++++++---
net/netfilter/nfnetlink.c | 10 +++++++---
2 files changed, 16 insertions(+), 6 deletions(-)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index ca4c4d994ddb..61e8846a99ad 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -6438,7 +6438,7 @@ static void nf_tables_abort_release(struct nft_trans *trans)
kfree(trans);
}
-static int nf_tables_abort(struct net *net, struct sk_buff *skb)
+static int __nf_tables_abort(struct net *net)
{
struct nft_trans *trans, *next;
struct nft_trans_elem *te;
@@ -6554,6 +6554,11 @@ static void nf_tables_cleanup(struct net *net)
nft_validate_state_update(net, NFT_VALIDATE_SKIP);
}
+static int nf_tables_abort(struct net *net, struct sk_buff *skb)
+{
+ return __nf_tables_abort(net);
+}
+
static bool nf_tables_valid_genid(struct net *net, u32 genid)
{
return net->nft.base_seq == genid;
@@ -7148,9 +7153,10 @@ static int __net_init nf_tables_init_net(struct net *net)
static void __net_exit nf_tables_exit_net(struct net *net)
{
+ if (!list_empty(&net->nft.commit_list))
+ __nf_tables_abort(net);
__nft_release_tables(net);
WARN_ON_ONCE(!list_empty(&net->nft.tables));
- WARN_ON_ONCE(!list_empty(&net->nft.commit_list));
}
static struct pernet_operations nf_tables_net_ops = {
@@ -7192,9 +7198,9 @@ static int __init nf_tables_module_init(void)
static void __exit nf_tables_module_exit(void)
{
- unregister_pernet_subsys(&nf_tables_net_ops);
nfnetlink_subsys_unregister(&nf_tables_subsys);
unregister_netdevice_notifier(&nf_tables_flowtable_notifier);
+ unregister_pernet_subsys(&nf_tables_net_ops);
rcu_barrier();
nf_tables_core_module_exit();
kfree(info);
diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c
index 4d0da7042aff..e1b6be29848d 100644
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -429,7 +429,7 @@ static void nfnetlink_rcv_batch(struct sk_buff *skb, struct nlmsghdr *nlh,
*/
if (err == -EAGAIN) {
status |= NFNL_BATCH_REPLAY;
- goto next;
+ goto done;
}
}
ack:
@@ -456,7 +456,7 @@ static void nfnetlink_rcv_batch(struct sk_buff *skb, struct nlmsghdr *nlh,
if (err)
status |= NFNL_BATCH_FAILURE;
}
-next:
+
msglen = NLMSG_ALIGN(nlh->nlmsg_len);
if (msglen > skb->len)
msglen = skb->len;
@@ -464,7 +464,11 @@ static void nfnetlink_rcv_batch(struct sk_buff *skb, struct nlmsghdr *nlh,
}
done:
if (status & NFNL_BATCH_REPLAY) {
- ss->abort(net, oskb);
+ const struct nfnetlink_subsystem *ss2;
+
+ ss2 = nfnl_dereference_protected(subsys_id);
+ if (ss2 == ss)
+ ss->abort(net, oskb);
nfnl_err_reset(&err_list);
nfnl_unlock(subsys_id);
kfree_skb(skb);
--
2.16.4
--
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
