From patchwork Wed Feb 22 03:46:37 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhanghailiang X-Patchwork-Id: 9586147 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 3175D6020B for ; Wed, 22 Feb 2017 04:04:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0BAD32865D for ; Wed, 22 Feb 2017 04:04:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 003B62867E; Wed, 22 Feb 2017 04:04:52 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 1E8C82865D for ; Wed, 22 Feb 2017 04:04:52 +0000 (UTC) Received: from localhost ([::1]:49749 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cgOAd-0008Ob-8W for patchwork-qemu-devel@patchwork.kernel.org; Tue, 21 Feb 2017 23:04:51 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43475) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cgNtb-0008Pe-Oa for qemu-devel@nongnu.org; Tue, 21 Feb 2017 22:47:16 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cgNta-0004nR-MF for qemu-devel@nongnu.org; Tue, 21 Feb 2017 22:47:15 -0500 Received: from [45.249.212.187] (port=2981 helo=dggrg01-dlp.huawei.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_ARCFOUR_SHA1:16) (Exim 4.71) (envelope-from ) id 1cgNta-0004lx-12 for qemu-devel@nongnu.org; Tue, 21 Feb 2017 22:47:14 -0500 Received: from 172.30.72.57 (EHLO DGGEMM406-HUB.china.huawei.com) ([172.30.72.57]) by dggrg01-dlp.huawei.com (MOS 4.4.6-GA FastPath queued) with ESMTP id AJN09258; Wed, 22 Feb 2017 11:47:10 +0800 (CST) Received: from DGGEML402-HUB.china.huawei.com (10.3.17.38) by DGGEMM406-HUB.china.huawei.com (10.3.20.214) with Microsoft SMTP Server (TLS) id 14.3.301.0; Wed, 22 Feb 2017 11:47:09 +0800 Received: from localhost (10.177.24.212) by DGGEML402-HUB.china.huawei.com (10.3.17.38) with Microsoft SMTP Server id 14.3.301.0; Wed, 22 Feb 2017 11:47:00 +0800 From: zhanghailiang To: , , Date: Wed, 22 Feb 2017 11:46:37 +0800 Message-ID: <1487735198-127300-3-git-send-email-zhang.zhanghailiang@huawei.com> X-Mailer: git-send-email 2.7.2.windows.1 In-Reply-To: <1487735198-127300-1-git-send-email-zhang.zhanghailiang@huawei.com> References: <1487735198-127300-1-git-send-email-zhang.zhanghailiang@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.177.24.212] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020202.58AD09BE.01F7, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: a7601548b5b5da5aa233dfae925c3049 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.4.x-2.6.x [generic] [fuzzy] X-Received-From: 45.249.212.187 Subject: [Qemu-devel] [PATCH v2 2/3] filter-rewriter: fix memory leak for connection in connection_track_table X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: zhanghailiang , xuquan8@huawei.com, qemu-devel@nongnu.org, pss.wulizhen@huawei.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP After a net connection is closed, we didn't clear its releated resources in connection_track_table, which will lead to memory leak. Let't track the state of net connection, if it is closed, its related resources will be cleared up. Signed-off-by: zhanghailiang --- net/colo.h | 4 +++ net/filter-rewriter.c | 70 +++++++++++++++++++++++++++++++++++++++++++++------ 2 files changed, 67 insertions(+), 7 deletions(-) diff --git a/net/colo.h b/net/colo.h index 7c524f3..cd9027f 100644 --- a/net/colo.h +++ b/net/colo.h @@ -18,6 +18,7 @@ #include "slirp/slirp.h" #include "qemu/jhash.h" #include "qemu/timer.h" +#include "slirp/tcp.h" #define HASHTABLE_MAX_SIZE 16384 @@ -69,6 +70,9 @@ typedef struct Connection { * run once in independent tcp connection */ int syn_flag; + + int tcp_state; /* TCP FSM state */ + tcp_seq fin_ack_seq; /* the seq of 'fin=1,ack=1' */ } Connection; uint32_t connection_key_hash(const void *opaque); diff --git a/net/filter-rewriter.c b/net/filter-rewriter.c index c4ab91c..7e7ec35 100644 --- a/net/filter-rewriter.c +++ b/net/filter-rewriter.c @@ -60,9 +60,9 @@ static int is_tcp_packet(Packet *pkt) } /* handle tcp packet from primary guest */ -static int handle_primary_tcp_pkt(NetFilterState *nf, +static int handle_primary_tcp_pkt(RewriterState *rf, Connection *conn, - Packet *pkt) + Packet *pkt, ConnectionKey *key) { struct tcphdr *tcp_pkt; @@ -97,15 +97,45 @@ static int handle_primary_tcp_pkt(NetFilterState *nf, tcp_pkt->th_ack = htonl(ntohl(tcp_pkt->th_ack) + conn->offset); net_checksum_calculate((uint8_t *)pkt->data, pkt->size); + /* + * Case 1: + * The *server* side of this connect is VM, *client* tries to close + * the connection. + * + * We got 'ack=1' packets from client side, it acks 'fin=1, ack=1' + * packet from server side. From this point, we can ensure that there + * will be no packets in the connection, except that, some errors + * happen between the path of 'filter object' and vNIC, if this rare + * case really happen, we can still create a new connection, + * So it is safe to remove the connection from connection_track_table. + * + */ + if ((conn->tcp_state == TCPS_LAST_ACK) && + (ntohl(tcp_pkt->th_ack) == (conn->fin_ack_seq + 1))) { + fprintf(stderr, "Remove conn " + g_hash_table_remove(rf->connection_track_table, key); + } + } + /* + * Case 2: + * The *server* side of this connect is VM, *server* tries to close + * the connection. + * + * We got 'fin=1, ack=1' packet from client side, we need to + * record the seq of 'fin=1, ack=1' packet. + */ + if ((tcp_pkt->th_flags & (TH_ACK | TH_FIN)) == (TH_ACK | TH_FIN)) { + conn->fin_ack_seq = htonl(tcp_pkt->th_seq); + conn->tcp_state = TCPS_LAST_ACK; } return 0; } /* handle tcp packet from secondary guest */ -static int handle_secondary_tcp_pkt(NetFilterState *nf, +static int handle_secondary_tcp_pkt(RewriterState *rf, Connection *conn, - Packet *pkt) + Packet *pkt, ConnectionKey *key) { struct tcphdr *tcp_pkt; @@ -133,8 +163,34 @@ static int handle_secondary_tcp_pkt(NetFilterState *nf, tcp_pkt->th_seq = htonl(ntohl(tcp_pkt->th_seq) - conn->offset); net_checksum_calculate((uint8_t *)pkt->data, pkt->size); + /* + * Case 2: + * The *server* side of this connect is VM, *server* tries to close + * the connection. + * + * We got 'ack=1' packets from server side, it acks 'fin=1, ack=1' + * packet from client side. Like Case 1, there should be no packets + * in the connection from now know, But the difference here is + * if the packet is lost, We will get the resent 'fin=1,ack=1' packet. + * TODO: Fix above case. + */ + if ((conn->tcp_state == TCPS_LAST_ACK) && + (ntohl(tcp_pkt->th_ack) == (conn->fin_ack_seq + 1))) { + g_hash_table_remove(rf->connection_track_table, key); + } + } + /* + * Case 1: + * The *server* side of this connect is VM, *client* tries to close + * the connection. + * + * We got 'fin=1, ack=1' packet from server side, we need to + * record the seq of 'fin=1, ack=1' packet. + */ + if ((tcp_pkt->th_flags & (TH_ACK | TH_FIN)) == (TH_ACK | TH_FIN)) { + conn->fin_ack_seq = ntohl(tcp_pkt->th_seq); + conn->tcp_state = TCPS_LAST_ACK; } - return 0; } @@ -178,7 +234,7 @@ static ssize_t colo_rewriter_receive_iov(NetFilterState *nf, if (sender == nf->netdev) { /* NET_FILTER_DIRECTION_TX */ - if (!handle_primary_tcp_pkt(nf, conn, pkt)) { + if (!handle_primary_tcp_pkt(s, conn, pkt, &key)) { qemu_net_queue_send(s->incoming_queue, sender, 0, (const uint8_t *)pkt->data, pkt->size, NULL); packet_destroy(pkt, NULL); @@ -191,7 +247,7 @@ static ssize_t colo_rewriter_receive_iov(NetFilterState *nf, } } else { /* NET_FILTER_DIRECTION_RX */ - if (!handle_secondary_tcp_pkt(nf, conn, pkt)) { + if (!handle_secondary_tcp_pkt(s, conn, pkt, &key)) { qemu_net_queue_send(s->incoming_queue, sender, 0, (const uint8_t *)pkt->data, pkt->size, NULL); packet_destroy(pkt, NULL);