Subject: Re: Fw: ipsec hang

From: Patrick McHardy <[email-masked]>
Date: Wed, 24 Nov 2004 19:10:57 +0100

Andrew Morton wrote:

>Looks like one of the chains off xfrm_policy_list[] might have gone
>circular?
>
This patch fixes it. When a policy with a priority lower than an
existing policy is inserted, it loops forever on the existing policy.

Regards
Patrick

>Begin forwarded message:
>
>Date: Wed, 24 Nov 2004 01:34:49 +0100
>From: Marcin Gibu³a <[email-masked]>
>To: [email-masked]
>Subject: ipsec hang
>
>
>Hi,
>today I tried to configure ipsec on my linux workstation (with openswan) and 
>it hanged just after the init had run /etc/rc.d/init.d/ipsec start. 
>It was on linux-2.6.10-rc1-bk20, so I upgraded to 2.6.10-rc2-mm3 but it didn't 
>make any difference. 
>
>The alt-sysrq-p shows the following call trace:
>xfrm_policy_insert
>xfrm_netlink_rcv
>netlink_data_ready
>netlink_sendmsg
>sock_aio_write
>do_sync_write
>sock_map_fd
>sys_select
>vfs_write
>system_call
>

# This is a BitKeeper generated diff -Nru style patch.
#
# ChangeSet
#   2004/11/23 18:21:09-08:00 [email-masked] 
#   [XFRM]: Fix endless loop in xfrm_policy_insert
#   
#   The patch 'Fix policy update bug when increasing
#   priority of last policy' broke this, when a policy
#   with lower priority than an existing policy is inserted
#   xfrm_policy_insert loops forever.
#   
#   Signed-off-by: Patrick McHardy <[email-masked]>
#   Signed-off-by: David S. Miller <[email-masked]>
# 
# net/xfrm/xfrm_policy.c
#   2004/11/23 18:20:49-08:00 [email-masked] +1 -0
#   [XFRM]: Fix endless loop in xfrm_policy_insert
#   
#   The patch 'Fix policy update bug when increasing
#   priority of last policy' broke this, when a policy
#   with lower priority than an existing policy is inserted
#   xfrm_policy_insert loops forever.
#   
#   Signed-off-by: Patrick McHardy <[email-masked]>
#   Signed-off-by: David S. Miller <[email-masked]>
# 
diff -Nru a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
--- a/net/xfrm/xfrm_policy.c	2004-11-24 19:01:38 +01:00
+++ b/net/xfrm/xfrm_policy.c	2004-11-24 19:01:38 +01:00
@@ -353,6 +353,7 @@
 			newpos = p;
 		if (delpol)
 			break;
+		p = &pol->next;
 	}
 	if (newpos)
 		p = newpos;