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4.74. iptables

Updated iptables packages that fix several bugs and add two enhancements are now available for Red Hat Enterprise Linux 5.
The iptables utility controls the network packet filtering code in the Linux kernel.

Bug Fixes

Prior to this update, the memory alignment of ipt_connlimit_data was incorrect on x86-based systems. An error message in the format "ip_tables: connlimit match: invalid size" was logged. This update adds an explicit alignment attribute to the ipt_connlimit_data structure to correct this.
The sysctl values for netfilter kernel modules were not restored after a firewall restart. Consequently, the firewall did not always perform as expected after a restart. This update applies a patch to optionally load sysctl settings on iptables start, if specified by the user in the /etc/sysctl.conf file. Users can now define sysctl settings to load on start and restart.
Prior to this update, the kernel netfilter modules were not loaded at all times. Consequently, some commands did not perform as expected the first time they were executed. With this update, a patch has been applied to ensure the modules are properly loaded and the problem no longer occurs.


Prior to this update, the statistic match module was not included in the iptables package. With this update, this module in now included.
A service reload option has been added to enable a refresh of the firewall rules without unloading netfilter kernel modules and dropping connections.
Users are advised to upgrade to these updated iptables packages, which fix these bugs and add these enhancements.