From d503b30bd648b3cb4e5f50b65d27e389960cc6d9 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Thu, 17 Feb 2011 11:32:38 +0100 Subject: netfilter: tproxy: do not assign timewait sockets to skb->sk Assigning a socket in timewait state to skb->sk can trigger kernel oops, e.g. in nfnetlink_log, which does: if (skb->sk) { read_lock_bh(&skb->sk->sk_callback_lock); if (skb->sk->sk_socket && skb->sk->sk_socket->file) ... in the timewait case, accessing sk->sk_callback_lock and sk->sk_socket is invalid. Either all of these spots will need to add a test for sk->sk_state != TCP_TIME_WAIT, or xt_TPROXY must not assign a timewait socket to skb->sk. This does the latter. If a TW socket is found, assign the tproxy nfmark, but skip the skb->sk assignment, thus mimicking behaviour of a '-m socket .. -j MARK/ACCEPT' re-routing rule. The 'SYN to TW socket' case is left unchanged -- we try to redirect to the listener socket. Cc: Balazs Scheidler Cc: KOVACS Krisztian Signed-off-by: Florian Westphal Signed-off-by: Patrick McHardy --- include/net/netfilter/nf_tproxy_core.h | 12 +----------- 1 file changed, 1 insertion(+), 11 deletions(-) (limited to 'include/net') diff --git a/include/net/netfilter/nf_tproxy_core.h b/include/net/netfilter/nf_tproxy_core.h index cd85b3bc832..e505358d899 100644 --- a/include/net/netfilter/nf_tproxy_core.h +++ b/include/net/netfilter/nf_tproxy_core.h @@ -201,18 +201,8 @@ nf_tproxy_get_sock_v6(struct net *net, const u8 protocol, } #endif -static inline void -nf_tproxy_put_sock(struct sock *sk) -{ - /* TIME_WAIT inet sockets have to be handled differently */ - if ((sk->sk_protocol == IPPROTO_TCP) && (sk->sk_state == TCP_TIME_WAIT)) - inet_twsk_put(inet_twsk(sk)); - else - sock_put(sk); -} - /* assign a socket to the skb -- consumes sk */ -int +void nf_tproxy_assign_sock(struct sk_buff *skb, struct sock *sk); #endif -- cgit v1.2.3-70-g09d2