[GIT PULL nf] IPVS fixes for v3.10

[GIT PULL nf] IPVS fixes for v3.10

[Simon Horman]

Hi Pablo,

The following changes since commit 4f36ea6eed2081340c7a7aa98c73187ecfccebff:

  netfilter: ipt_ULOG: fix non-null terminated string in the nf_log path (2013-05-23 14:25:40 +0200)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs.git tags/ipvs-fixes-for-v3.10

for you to fetch changes up to 1fb4f80a593231770eae3192e4a52fa7631bd897:

  ipvs: Fix reuse connection if real server is dead (2013-05-26 08:10:47 +0900)

----------------------------------------------------------------
IPVS fixes for v3.10

Correct connection reuse for TCP and SCTP

----------------------------------------------------------------
Grzegorz Lyczba (1):
      ipvs: Fix reuse connection if real server is dead

 net/netfilter/ipvs/ip_vs_core.c |   35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

[PATCH] ipvs: Fix reuse connection if real server is dead

[Simon Horman]

From: Grzegorz Lyczba <grzegorz.lyczba@gmail.com>

Expire cached connection for new TCP/SCTP connection if real server is down

Signed-off-by: Grzegorz Lyczba <grzegorz.lyczba@gmail.com>
Acked-by: Hans Schillstrom <hans@schillstrom.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 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 085b588..05565d2 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
-- 
1.7.10.4

Re: [PATCH] ipvs: Fix reuse connection if real server is dead

[Pablo Neira Ayuso]

On Sun, May 26, 2013 at 08:16:39AM +0900, Simon Horman wrote:
> From: Grzegorz Lyczba <grzegorz.lyczba@gmail.com>
> 
> Expire cached connection for new TCP/SCTP connection if real server is down

Applied, thanks Simon.

I have mangled the description to insist on the fact that newly
(reused) connections break as they will be directed to the dead
server.

Re: [PATCH] ipvs: Fix reuse connection if real server is dead

[Simon Horman]

On Mon, May 27, 2013 at 01:49:11PM +0200, Pablo Neira Ayuso wrote:
> On Sun, May 26, 2013 at 08:16:39AM +0900, Simon Horman wrote:
> > From: Grzegorz Lyczba <grzegorz.lyczba@gmail.com>
> > 
> > Expire cached connection for new TCP/SCTP connection if real server is down
> 
> Applied, thanks Simon.
> 
> I have mangled the description to insist on the fact that newly
> (reused) connections break as they will be directed to the dead
> server.

Thanks.