Bug 439358 - iptables/netfilter handles CIDR notation incorrectly
Summary: iptables/netfilter handles CIDR notation incorrectly
Keywords:
Status: CLOSED CANTFIX
Alias: None
Product: Red Hat Enterprise Linux 5
Classification: Red Hat
Component: iptables
Version: 5.3
Hardware: All
OS: Linux
low
low
Target Milestone: rc
: ---
Assignee: iptables-maint-list
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2008-03-28 08:53 UTC by Jason Roysdon
Modified: 2008-07-15 14:38 UTC (History)
0 users

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2008-07-15 14:38:03 UTC
Target Upstream Version:
Embargoed:

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Description Jason Roysdon 2008-03-28 08:53:58 UTC 
Description of problem:
iptables handles cidr notation wrong.  This is fixed upstream in netfilter 1.3.6
as bug #422:
https://bugzilla.netfilter.org/cgi-bin/bugzilla/show_bug.cgi?id=422

Version-Release number of selected component (if applicable):
1.3.5

How reproducible:
Create the following rule:
-A RH-Firewall-1-INPUT -s 121.254.128/17 -j DROP

  
Actual results:
121.254.0.0/17

Expected results:
121.254.128.0/17

Additional info:
Temp work-around to add all 4 octets first (useful when importing large lists):
awk -F '[/.]' '{mask=$NF;$NF=0; printf "%d.%d.%d.%d/%d\n",$1,$2,$3,$4,mask}'
Comment 1 Thomas Woerner 2008-07-15 14:38:03 UTC 
I do not think that it is good to change the behavior here. People might be
using the current scheme and an update will break it.

I am closing this CANTFIX.
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