From mboxrd@z Thu Jan 1 00:00:00 1970 From: yangxingwu Subject: [PATCH v2] ipvs: Fix reuse connection if RS weight is 0 Date: Fri, 29 Oct 2021 11:26:04 +0800 Message-ID: <20211029032604.5432-1-xingwu.yang@gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=LtgP/cUoxxhvYcfdihWX13hRZAIDcFCne2uXGpi/AnA=; b=pnVPSE1jjdTlHf5q+/QOUvnEnDh/dyo56Nltoztkn7rp+u2qIthB4nz3zQts+FpEaC ztX77ZUZG39hwxvuBeOUVCq5ol3T6+oOYJa8bHnbXZE2cWTGG1Qf0O0YXl73KaFpu0iQ CQXkjEnU7IFLnvn1f+Ij2haWAY7oY5krONTZ2Xss/PowjeSm5Eo0LA9lKrxzzz6qm9qz X7/4eE9kpYZ+AKwDk8M+IgYdSOGwXG1VqZ6gjFdouNpSWYHLJ8iiRXPGpy33W6w4GqTc D3PDOZdA/hsQZ5Em7wFXVcQrmlWHF8ctOokrHC4PdaoO1KdkhrtW38ry8HxfVeJYrwJg f9kA== List-ID: Content-Type: text/plain; charset="us-ascii" To: horms@verge.net.au Cc: ja@ssi.bg, pablo@netfilter.org, kadlec@netfilter.org, fw@strlen.de, davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org, lvs-devel@vger.kernel.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, corbet@lwn.net, xingwu.yang@gmail.com, legend050709@qq.com Since commit dc7b3eb900aa ("ipvs: Fix reuse connection if real server is dead"), new connections to dead servers are redistributed immediately to new servers. Then commit d752c3645717 ("ipvs: allow rescheduling of new connections when port reuse is detected") disable expire_nodest_conn if conn_reuse_mode is 0. And new connection may be distributed to a real server with weight 0. Co-developed-by: Chuanqi Liu Signed-off-by: Chuanqi Liu Signed-off-by: yangxingwu --- Documentation/networking/ipvs-sysctl.rst | 3 +-- net/netfilter/ipvs/ip_vs_core.c | 7 ++++--- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/Documentation/networking/ipvs-sysctl.rst b/Documentation/networking/ipvs-sysctl.rst index 2afccc63856e..1cfbf1add2fc 100644 --- a/Documentation/networking/ipvs-sysctl.rst +++ b/Documentation/networking/ipvs-sysctl.rst @@ -37,8 +37,7 @@ conn_reuse_mode - INTEGER 0: disable any special handling on port reuse. The new connection will be delivered to the same real server that was - servicing the previous connection. This will effectively - disable expire_nodest_conn. + servicing the previous connection. bit 1: enable rescheduling of new connections when it is safe. That is, whenever expire_nodest_conn and for TCP sockets, when diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c index 128690c512df..374f4b0b7080 100644 --- a/net/netfilter/ipvs/ip_vs_core.c +++ b/net/netfilter/ipvs/ip_vs_core.c @@ -2042,14 +2042,15 @@ ip_vs_in(struct netns_ipvs *ipvs, unsigned int hooknum, struct sk_buff *skb, int ipvs, af, skb, &iph); conn_reuse_mode = sysctl_conn_reuse_mode(ipvs); - if (conn_reuse_mode && !iph.fragoffs && is_new_conn(skb, &iph) && cp) { + if (!iph.fragoffs && is_new_conn(skb, &iph) && cp) { bool old_ct = false, resched = false; if (unlikely(sysctl_expire_nodest_conn(ipvs)) && cp->dest && - unlikely(!atomic_read(&cp->dest->weight))) { + unlikely(!atomic_read(&cp->dest->weight)) && !cp->control) { resched = true; old_ct = ip_vs_conn_uses_old_conntrack(cp, skb); - } else if (is_new_conn_expected(cp, conn_reuse_mode)) { + } else if (conn_reuse_mode && + is_new_conn_expected(cp, conn_reuse_mode)) { old_ct = ip_vs_conn_uses_old_conntrack(cp, skb); if (!atomic_read(&cp->n_control)) { resched = true; -- 2.30.2