path: root/net/netfilter
diff options
authorFlorian Westphal <fw@strlen.de>2013-02-12 05:59:53 +0000
committerPablo Neira Ayuso <pablo@gnumonks.org>2013-02-12 23:20:46 +0100
commit6e2f0aa8cf8892868bf2c19349cb5d7c407f690d (patch)
tree9cf81b07af02e67f2efd036b5100a0dd36036a20 /net/netfilter
parent442fad9423b78319e0019a7f5047eddf3317afbc (diff)
netfilter: nf_ct_helper: don't discard helper if it is actually the same
commit (32f5376 netfilter: nf_ct_helper: disable automatic helper re-assignment of different type) broke transparent proxy scenarios. For example, initial helper lookup might yield "ftp" (dport 21), while re-lookup after REDIRECT yields "ftp-2121". This causes the autoassign code to toss the ftp helper, even though these are just different instances of the same helper. Change the test to check for the helper function address instead of the helper address, as suggested by Pablo. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@gnumonks.org>
Diffstat (limited to 'net/netfilter')
1 files changed, 3 insertions, 1 deletions
diff --git a/net/netfilter/nf_conntrack_helper.c b/net/netfilter/nf_conntrack_helper.c
index 884f2b39319..91527d5ba01 100644
--- a/net/netfilter/nf_conntrack_helper.c
+++ b/net/netfilter/nf_conntrack_helper.c
@@ -236,7 +236,9 @@ int __nf_ct_try_assign_helper(struct nf_conn *ct, struct nf_conn *tmpl,
/* We only allow helper re-assignment of the same sort since
* we cannot reallocate the helper extension area.
- if (help->helper != helper) {
+ struct nf_conntrack_helper *tmp = rcu_dereference(help->helper);
+ if (tmp && tmp->help != helper->help) {
RCU_INIT_POINTER(help->helper, NULL);
goto out;