From dc7b3eb900aab02e5cafbca3948d005be13fb4a5 Mon Sep 17 00:00:00 2001 From: Grzegorz Lyczba Date: Mon, 13 May 2013 23:56:24 +0200 Subject: [PATCH] ipvs: Fix reuse connection if real server is dead Expire cached connection for new TCP/SCTP connection if real server is down. Otherwise, IPVS uses the dead server for the reused connection, instead of a new working one. Signed-off-by: Grzegorz Lyczba Acked-by: Hans Schillstrom Acked-by: Julian Anastasov Signed-off-by: Simon Horman Signed-off-by: Pablo Neira Ayuso --- net/netfilter/ipvs/ip_vs_core.c | 35 +++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c index 085b5880ab0d..05565d2b3a61 100644 --- a/net/netfilter/ipvs/ip_vs_core.c +++ b/net/netfilter/ipvs/ip_vs_core.c @@ -1001,6 +1001,32 @@ static inline int is_tcp_reset(const struct sk_buff *skb, int nh_len) return th->rst; } +static inline bool is_new_conn(const struct sk_buff *skb, + struct ip_vs_iphdr *iph) +{ + switch (iph->protocol) { + case IPPROTO_TCP: { + struct tcphdr _tcph, *th; + + th = skb_header_pointer(skb, iph->len, sizeof(_tcph), &_tcph); + if (th == NULL) + return false; + return th->syn; + } + case IPPROTO_SCTP: { + sctp_chunkhdr_t *sch, schunk; + + sch = skb_header_pointer(skb, iph->len + sizeof(sctp_sctphdr_t), + sizeof(schunk), &schunk); + if (sch == NULL) + return false; + return sch->type == SCTP_CID_INIT; + } + default: + return false; + } +} + /* Handle response packets: rewrite addresses and send away... */ static unsigned int @@ -1612,6 +1638,15 @@ ip_vs_in(unsigned int hooknum, struct sk_buff *skb, int af) * Check if the packet belongs to an existing connection entry */ cp = pp->conn_in_get(af, skb, &iph, 0); + + if (unlikely(sysctl_expire_nodest_conn(ipvs)) && cp && cp->dest && + unlikely(!atomic_read(&cp->dest->weight)) && !iph.fragoffs && + is_new_conn(skb, &iph)) { + ip_vs_conn_expire_now(cp); + __ip_vs_conn_put(cp); + cp = NULL; + } + if (unlikely(!cp) && !iph.fragoffs) { /* No (second) fragments need to enter here, as nf_defrag_ipv6 * replayed fragment zero will already have created the cp