[PATCH net-next-2.6] [TPROXY] fixes a possible read from an unmapped location in the socket match

Balazs Scheidler
2008-12-07T18:43:40Z

TIME_WAIT sockets need to be handled specially, and the socket match
casted inet_timewait_sock instances to inet_sock, which are not
compatible. Handle this special case by checking sk->sk_state.
---
net/netfilter/xt_socket.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/net/netfilter/xt_socket.c b/net/netfilter/xt_socket.c
index 0e03922..1d521a5 100644
--- a/net/netfilter/xt_socket.c
+++ b/net/netfilter/xt_socket.c
@@ -144,7 +144,7 @@ socket_mt(const struct sk_buff *skb, const struct xt_match_param *par)
sk = nf_tproxy_get_sock_v4(dev_net(skb->dev), protocol,
saddr, daddr, sport, dport, par->in, false);
if (sk != NULL) {
- bool wildcard = (inet_sk(sk)->rcv_saddr == 0);
+ bool wildcard = (sk->sk_state != TCP_TIME_WAIT && inet_sk(sk)->rcv_saddr == 0);

nf_tproxy_put_sock(sk);
if (wildcard)
--
1.5.6.3