[GIT PULL nf-2.6] IPVS

Hi Pablo,

please consider pulling
git://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs-2.6.git master
to get the following fix from Hans.

I believe this change should be considered for -stable.

Hans Schillstrom (1):
      IPVS netns exit causes crash in conntrack

From: Hans Schillstrom <redacted>

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 <redacted>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 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);
 }

-- 
1.7.4.4

On 13.06.2011 10:47, Simon Horman wrote:

Hi Pablo,

please consider pulling
git://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs-2.6.git master
to get the following fix from Hans.

I believe this change should be considered for -stable.

Just send it to the stable people once it hits upstream. I'll
send it to Dave tonight.

Hans Schillstrom (1):
      IPVS netns exit causes crash in conntrac

Pulled, thanks Simon.

On Thu, Jun 16, 2011 at 05:11:10PM +0200, Patrick McHardy wrote:

On 13.06.2011 10:47, Simon Horman wrote:

quoted

Hi Pablo,

please consider pulling
git://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs-2.6.git master
to get the following fix from Hans.

I believe this change should be considered for -stable.

Just send it to the stable people once it hits upstream. I'll
send it to Dave tonight.

Understood, will do.