[NETFILTER]: conntrack: don't call helpers for related ICMP messages

None of the existing helpers expects to get called for related ICMP
packets and some even drop them if they can't parse them.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/netfilter/ip_conntrack_standalone.c b/net/ipv4/netfilter/ip_conntrack_standalone.c
index 929d61f..f0cc7fe 100644 (file)
--- a/net/ipv4/netfilter/ip_conntrack_standalone.c
+++ b/net/ipv4/netfilter/ip_conntrack_standalone.c
@@ -417,7 +417,7 @@ static unsigned int ip_conntrack_help(unsigned int hooknum,
 
        /* This is where we call the helper: as the packet goes out. */
        ct = ip_conntrack_get(*pskb, &ctinfo);
-       if (ct && ct->helper) {
+       if (ct && ct->helper && ctinfo != IP_CT_RELATED + IP_CT_IS_REPLY) {
                unsigned int ret;
                ret = ct->helper->help(pskb, ct, ctinfo);
                if (ret != NF_ACCEPT)

diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
index 77d9744..8cc8e1b 100644 (file)
--- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
+++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
@@ -145,7 +145,7 @@ static unsigned int ipv4_conntrack_help(unsigned int hooknum,
 
        /* This is where we call the helper: as the packet goes out. */
        ct = nf_ct_get(*pskb, &ctinfo);
-       if (!ct)
+       if (!ct || ctinfo == IP_CT_RELATED + IP_CT_IS_REPLY)
                return NF_ACCEPT;
 
        help = nfct_help(ct);

diff --git a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
index 93bae36..2a71c3b 100644 (file)
--- a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
+++ b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
@@ -189,7 +189,7 @@ static unsigned int ipv6_confirm(unsigned int hooknum,
 
        /* This is where we call the helper: as the packet goes out. */
        ct = nf_ct_get(*pskb, &ctinfo);
-       if (!ct)
+       if (!ct || ctinfo == IP_CT_RELATED + IP_CT_IS_REPLY)
                goto out;
 
        help = nfct_help(ct);