From mboxrd@z Thu Jan 1 00:00:00 1970 From: kaber@trash.net Subject: [PATCH 1/6] IPVS netns exit causes crash in conntrack Date: Thu, 16 Jun 2011 21:41:36 +0200 Message-ID: <1308253301-29894-2-git-send-email-kaber@trash.net> References: <1308253301-29894-1-git-send-email-kaber@trash.net> Cc: netfilter-devel@vger.kernel.org, netdev@vger.kernel.org To: davem@davemloft.net Return-path: In-Reply-To: <1308253301-29894-1-git-send-email-kaber@trash.net> Sender: netdev-owner@vger.kernel.org List-Id: netfilter-devel.vger.kernel.org From: Hans Schillstrom Quote from Patric Mc Hardy "This looks like nfnetlink.c excited and destroyed the nfnl socket, but ip_vs was still holding a reference to a conntrack. When the conntrack got destroyed it created a ctnetlink event, causing an oops in netlink_has_listeners when trying to use the destroyed nfnetlink socket." If nf_conntrack_netlink is loaded before ip_vs this is not a problem. This patch simply avoids calling ip_vs_conn_drop_conntrack() when netns is dying as suggested by Julian. Signed-off-by: Hans Schillstrom Signed-off-by: Simon Horman --- net/netfilter/ipvs/ip_vs_conn.c | 10 +++++++++- net/netfilter/ipvs/ip_vs_core.c | 1 + 2 files changed, 10 insertions(+), 1 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c index bf28ac2..782db27 100644 --- a/net/netfilter/ipvs/ip_vs_conn.c +++ b/net/netfilter/ipvs/ip_vs_conn.c @@ -776,8 +776,16 @@ static void ip_vs_conn_expire(unsigned long data) if (cp->control) ip_vs_control_del(cp); - if (cp->flags & IP_VS_CONN_F_NFCT) + if (cp->flags & IP_VS_CONN_F_NFCT) { ip_vs_conn_drop_conntrack(cp); + /* Do not access conntracks during subsys cleanup + * because nf_conntrack_find_get can not be used after + * conntrack cleanup for the net. + */ + smp_rmb(); + if (ipvs->enable) + ip_vs_conn_drop_conntrack(cp); + } ip_vs_pe_put(cp->pe); kfree(cp->pe_data); diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c index 55af224..24c28d2 100644 --- a/net/netfilter/ipvs/ip_vs_core.c +++ b/net/netfilter/ipvs/ip_vs_core.c @@ -1945,6 +1945,7 @@ static void __net_exit __ip_vs_dev_cleanup(struct net *net) { EnterFunction(2); net_ipvs(net)->enable = 0; /* Disable packet reception */ + smp_wmb(); __ip_vs_sync_cleanup(net); LeaveFunction(2); } -- 1.7.2.3