[mpls-linux-devel] cannot remove iptables rule with mpls target / cannot remove nhlfe key used by iptables.

[Tom K. <t.k...@gm...>]

Hello,

I came across a problem with removing an mpls target from iptables.
Apparently, the problem was found previously and posted on the mailing list:
http://sourceforge.net/mailarchive/message.php?msg_id=58990.192.168.1.72.1177109560.squirrel%40webmail.larces.uece.br
http://sourceforge.net/mailarchive/message.php?msg_id=1801039839.20070421093542%40s2001.tu-chemnitz.de
http://sourceforge.net/mailarchive/message.php?msg_id=4631EBCD.8090708%40gmail.com

The target can be removed from iptables only by using the rule number
instead of the complete rule description.

Unfortunately, I encountered another issue, which could be related to this
one. Namely, when a nhfle key has been used by an iptables target and the
iptables rule is later removed,
then the key can no longer be removed from the nhlfe table. The key can now
only be removed from the nhlfe table by
rebooting the pc.

The following commands will show the error.
mpls nhlfe add key 0
iptables -t mangle -A OUTPUT <some rule> -j mpls --nhlfe <key>
iptables -t mangle -D OUTPUT <#some rule>
mpls nhlfe del key <key>

The last command will report the error:
RTNETLINK answers: Device or resource busy


dmesg reports:
MPLS DEBUG net/mpls/mpls_nhlfe.c:468:mpls_del_out_label: enter
MPLS DEBUG net/mpls/mpls_nhlfe.c:492:mpls_del_out_label: Node 4 is being
used
MPLS DEBUG net/mpls/mpls_nhlfe.c:493:mpls_del_out_label: exit
MPLS DEBUG net/mpls/mpls_netlink.c:346:genl_mpls_nhlfe_del: Exit: -16

Can anyone confirm this problem and is there a solution/workaround?

Kind regards,

Tom
t.k...@gm...