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7.86. iptables

Updated iptables packages that fix several bugs and add two enhancements are now available for Red Hat Enterprise Linux 6.
The iptables utility controls the network packet filtering code in the Linux kernel.

Bug Fixes

Previously, no iptables revision was used for rules that match an ipset. As a consequence, iptables rules with the match-set option could be added, but not removed again, as the rules could not be located again for their removal. This update adds revision 0 and 1 code patches for libipt_SET. As a result, new ipset match rules can now be removed. Please note that adding and removing rules using the match-set option now works with the patch applied, but removing a rule that was added with an earlier version of iptables does not work and cannot be fixed. Use the rule number to remove such rules.
In iptables version 1.4.7-9, the use of alternatives was introduced. Because of the use of versioned (/lib*/xtables-%{version}) custom plug-ins, the plug-ins had to be placed in the appropriate versioned plug-in directory. Starting with iptables version 1.4.7-10, the plug-in directory was reverted back to /lib*/xtables/, but custom plug-ins from iptables version 1.4.7-9 were not copied over. Consequently, upgrading iptables 1.4.7-9 to a newer version led to a loss of custom plug-ins. A plug-in update trigger which detects updates to iptables from version 1.4.7-15 and lower has been added. As a result, custom plug-ins from the /%{_lib}/xtables-1.4.7/ directory are copied to the /%{_lib}/xtables/ directory if the plug-in in /%{_lib}/xtables-1.4.7/ has a newer file date or if it does not exist in the destination directory while updating from iptables version earlier than 1.4.7-15 to a newer version.
Previously, a space after Datagram Congestion Control Protocol (DCCP) packet types for print and save was missing, which led to malformed output. With this update, a space has been added at the end of the print_types() function output. As a result, the output of the "iptables -L", "iptables -S", and iptables-save commands is now correct.
Previously, some init script warning messages for a failed euid 0 check (no configuration file and nothing to save) were missing. Consequently, only exit status codes were provided in these cases, but no messages. This update adds the warning messages that are now provided in the described situation.


This update adds support for IPv6 ipset, as ipsets were not previously usable in IPv6 firewall rules.
This update adds support for the "-C" check option for the ip*tables commands. Previously, there was no simple way to check if a certain rule exists. Now, the "-C" option can be used in a rule to check if a rule exists.
Users of iptables are advised to upgrade to these updated packages, which fix these bugs and add these enhancements.