From 0c12582fbcdea0cbb0dfd224e1c5f9a8428ffa18 Mon Sep 17 00:00:00 2001 From: Julian Anastasov Date: Sat, 9 Mar 2013 23:25:04 +0200 Subject: ipvs: add backup_only flag to avoid loops Dmitry Akindinov is reporting for a problem where SYNs are looping between the master and backup server when the backup server is used as real server in DR mode and has IPVS rules to function as director. Even when the backup function is enabled we continue to forward traffic and schedule new connections when the current master is using the backup server as real server. While this is not a problem for NAT, for DR and TUN method the backup server can not determine if a request comes from client or from director. To avoid such loops add new sysctl flag backup_only. It can be needed for DR/TUN setups that do not need backup and director function at the same time. When the backup function is enabled we stop any forwarding and pass the traffic to the local stack (real server mode). The flag disables the director function when the backup function is enabled. For setups that enable backup function for some virtual services and director function for other virtual services there should be another more complex solution to support DR/TUN mode, may be to assign per-virtual service syncid value, so that we can differentiate the requests. Reported-by: Dmitry Akindinov Tested-by: German Myzovsky Signed-off-by: Julian Anastasov Signed-off-by: Simon Horman --- include/net/ip_vs.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'include/net') diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h index 68c69d54d39..fce8e6b66d5 100644 --- a/include/net/ip_vs.h +++ b/include/net/ip_vs.h @@ -976,6 +976,7 @@ struct netns_ipvs { int sysctl_sync_retries; int sysctl_nat_icmp_send; int sysctl_pmtu_disc; + int sysctl_backup_only; /* ip_vs_lblc */ int sysctl_lblc_expiration; @@ -1067,6 +1068,12 @@ static inline int sysctl_pmtu_disc(struct netns_ipvs *ipvs) return ipvs->sysctl_pmtu_disc; } +static inline int sysctl_backup_only(struct netns_ipvs *ipvs) +{ + return ipvs->sync_state & IP_VS_STATE_BACKUP && + ipvs->sysctl_backup_only; +} + #else static inline int sysctl_sync_threshold(struct netns_ipvs *ipvs) @@ -1114,6 +1121,11 @@ static inline int sysctl_pmtu_disc(struct netns_ipvs *ipvs) return 1; } +static inline int sysctl_backup_only(struct netns_ipvs *ipvs) +{ + return 0; +} + #endif /* -- cgit v1.2.3-70-g09d2 From 8ed781668dd49b608f1e67a22e3b445fd0c2cd6f Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Tue, 19 Mar 2013 06:39:29 +0000 Subject: flow_keys: include thoff into flow_keys for later usage In skb_flow_dissect(), we perform a dissection of a skbuff. Since we're doing the work here anyway, also store thoff for a later usage, e.g. in the BPF filter. Suggested-by: Eric Dumazet Signed-off-by: Daniel Borkmann Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/flow_keys.h | 1 + net/core/flow_dissector.c | 2 ++ 2 files changed, 3 insertions(+) (limited to 'include/net') diff --git a/include/net/flow_keys.h b/include/net/flow_keys.h index 80461c1ae9e..bb8271d487b 100644 --- a/include/net/flow_keys.h +++ b/include/net/flow_keys.h @@ -9,6 +9,7 @@ struct flow_keys { __be32 ports; __be16 port16[2]; }; + u16 thoff; u8 ip_proto; }; diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 9d4c7201400..e187bf06d67 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -140,6 +140,8 @@ ipv6: flow->ports = *ports; } + flow->thoff = (u16) nhoff; + return true; } EXPORT_SYMBOL(skb_flow_dissect); -- cgit v1.2.3-70-g09d2 From 330305cc4a6b0cb75c22fc01b8826f0ad755550f Mon Sep 17 00:00:00 2001 From: Pravin B Shelar Date: Sun, 24 Mar 2013 17:36:29 +0000 Subject: ipv4: Fix ip-header identification for gso packets. ip-header id needs to be incremented even if IP_DF flag is set. This behaviour was changed in commit 490ab08127cebc25e3a26 (IP_GRE: Fix IP-Identification). Following patch fixes it so that identification is always incremented. Reported-by: Cong Wang Signed-off-by: Pravin B Shelar Signed-off-by: David S. Miller --- include/net/ipip.h | 16 ++++++---------- net/ipv4/af_inet.c | 3 +-- 2 files changed, 7 insertions(+), 12 deletions(-) (limited to 'include/net') diff --git a/include/net/ipip.h b/include/net/ipip.h index fd19625ff99..982141c1520 100644 --- a/include/net/ipip.h +++ b/include/net/ipip.h @@ -77,15 +77,11 @@ static inline void tunnel_ip_select_ident(struct sk_buff *skb, { struct iphdr *iph = ip_hdr(skb); - if (iph->frag_off & htons(IP_DF)) - iph->id = 0; - else { - /* Use inner packet iph-id if possible. */ - if (skb->protocol == htons(ETH_P_IP) && old_iph->id) - iph->id = old_iph->id; - else - __ip_select_ident(iph, dst, - (skb_shinfo(skb)->gso_segs ?: 1) - 1); - } + /* Use inner packet iph-id if possible. */ + if (skb->protocol == htons(ETH_P_IP) && old_iph->id) + iph->id = old_iph->id; + else + __ip_select_ident(iph, dst, + (skb_shinfo(skb)->gso_segs ?: 1) - 1); } #endif diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 68f6a94f766..c929d9c1c4b 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1333,8 +1333,7 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, iph->frag_off |= htons(IP_MF); offset += (skb->len - skb->mac_len - iph->ihl * 4); } else { - if (!(iph->frag_off & htons(IP_DF))) - iph->id = htons(id++); + iph->id = htons(id++); } iph->tot_len = htons(skb->len - skb->mac_len); iph->check = 0; -- cgit v1.2.3-70-g09d2