Bug 210119

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User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.8.0.7) Gecko/20060913 Fedora/1.5.0.7-1.fc5 Firefox/1.5.0.7 pango-text

Description of problem:
When an iptables NAT rule is loaded (which causes the loading the modules ip_conntrack,xt_state,ipt_MASQUERADE,iptable_nat,ip_nat) and an external connection is made to the machine over another (non-iptables filtered) gigabit ethernet-card, and there is a reasonable amount of traffic from the machine outbound (like issueing 'dmesg' over an SSH connection) then there is an immediate kernel panic.
This happens with multiple types of ethernet cards (intel Pro1000, Realtec, Sky2).
If the firewall NAT rules are unloaded, but the ip_conntrack module(s) are still loaded, then the problem still exists.
If the ip_conntrack module is also unloaded then the problem does not happen anymore.

Version-Release number of selected component (if applicable):
kernel-2.6.17-1.2187_FC5, iptables-1.3.5-1.2

How reproducible:
Always


Steps to Reproduce:
1. Do an FC5 installation on a Pentium D940 Dual Core x86_64 machine with mulitiple gigabit ethernet cards.
2. Load an iptables NAT rule on ethernet card eth1.
3. Establish an SSH connection from an external machine to the x86_64 machine inbound over eth0.
4. Type: 'dmesg'

Actual Results:
Kernel Panic.

Expected Results:
No kernel panic, just the output of dmesg over SSH.

Additional info:
Just typeing 'ls' over SSH does not trigger the problem.
It can also be reproduced by other (more 'heavy') ethernet traffic.

The machine is running with Intel D940 Dual-core 3.2GHz, Asus P5WD2-Premium motherboard, 3x SATA-2 Maxtor 6H500F0 disks, Software RAID5, LVM2, Ext3, 1GB of PC6400 DDR2 memory (800MHz FSB).

# lspci
00:00.0 Host bridge: Intel Corporation Memory Controller Hub (rev c0)
00:01.0 PCI bridge: Intel Corporation PCI Express Graphics Port (rev c0)
00:1b.0 Audio device: Intel Corporation 82801G (ICH7 Family) High Definition Audio Controller (rev 01)
00:1c.0 PCI bridge: Intel Corporation 82801G (ICH7 Family) PCI Express Port 1 (rev 01)
00:1c.5 PCI bridge: Intel Corporation 82801GR/GH/GHM (ICH7 Family) PCI Express Port 6 (rev 01)
00:1d.0 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI #1 (rev 01)
00:1d.1 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI #2 (rev 01)
00:1d.2 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI #3 (rev 01)
00:1d.3 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI #4 (rev 01)
00:1d.7 USB Controller: Intel Corporation 82801G (ICH7 Family) USB2 EHCI Controller (rev 01)
00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev e1)
00:1f.0 ISA bridge: Intel Corporation 82801GB/GR (ICH7 Family) LPC Interface Bridge (rev 01)
00:1f.1 IDE interface: Intel Corporation 82801G (ICH7 Family) IDE Controller (rev 01)
00:1f.2 SATA controller: Intel Corporation 82801GR/GH (ICH7 Family) Serial ATA Storage Controllers cc=AHCI (rev 01)
00:1f.3 SMBus: Intel Corporation 82801G (ICH7 Family) SMBus Controller (rev 01)
01:00.0 Ethernet controller: Intel Corporation 82541GI/PI Gigabit Ethernet Controller
01:01.0 Ethernet controller: Intel Corporation 82540EM Gigabit Ethernet Controller (rev 02)
01:02.0 Ethernet controller: Intel Corporation 82541GI/PI Gigabit Ethernet Controller
01:03.0 FireWire (IEEE 1394): Texas Instruments TSB43AB22/A IEEE-1394a-2000 Controller (PHY/Link)
02:00.0 SATA controller: Marvell Technology Group Ltd. Unknown device 6141 (rev 01)
04:00.0 VGA compatible controller: nVidia Corporation GeForce 6200 TurboCache(TM) (rev a1)