Just trying to get my ethernet connection to work in Oneiric, and when I plug the cable in it connects and disconnects forever. /var/syslog says this (repeats it over and over again):

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) successful, device activated.

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 5 of 5 (IP Configure Commit) complete.

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 4 of 5 (IP4 Configure Get) complete.

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <warn> dnsmasq exited with error: Network access problem (address in use; permissions; etc) (2)

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> (eth0): device state change: activated -> failed (reason 'sharing-start-failed') [100 120 18]

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <warn> Activation (eth0) failed.

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> (eth0): device state change: failed -> disconnected (reason 'none') [120 30 0]

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> (eth0): deactivating device (reason 'none') [0]

Sep 26 17:06:47 X58A-UD3R avahi-daemon[1321]: Withdrawing address record for 10.42.43.1 on eth0.

Sep 26 17:06:47 X58A-UD3R avahi-daemon[1321]: Leaving mDNS multicast group on interface eth0.IPv4 with address 10.42.43.1.

Sep 26 17:06:47 X58A-UD3R avahi-daemon[1321]: Interface eth0.IPv4 no longer relevant for mDNS.

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Clearing nscd hosts cache.

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table nat --delete POSTROUTING --source 10.42.43.0/255.255.255.0 ! --destination 10.42.43.0/255.255.255.0 --jump MASQUERADE

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --delete FORWARD --destination 10.42.43.0/255.255.255.0 --out-interface eth0 --match state --state ESTABLISHED,RELATED --jump ACCEPT

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --delete FORWARD --source 10.42.43.0/255.255.255.0 --in-interface eth0 --jump ACCEPT

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --delete FORWARD --in-interface eth0 --out-interface eth0 --jump ACCEPT

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --delete FORWARD --out-interface eth0 --jump REJECT

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --delete FORWARD --in-interface eth0 --jump REJECT

Sep 26 17:06:47 X58A-UD3R ntpdate[15004]: Can't find host ntp.ubuntu.com: Name or service not known (-2)

Sep 26 17:06:47 X58A-UD3R ntpdate[15004]: no servers can be used, exiting

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --delete INPUT --in-interface eth0 --protocol udp --destination-port 67 --jump ACCEPT

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --delete INPUT --in-interface eth0 --protocol tcp --destination-port 67 --jump ACCEPT

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --delete INPUT --in-interface eth0 --protocol udp --destination-port 53 --jump ACCEPT

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --delete INPUT --in-interface eth0 --protocol tcp --destination-port 53 --jump ACCEPT

Sep 26 17:06:47 X58A-UD3R avahi-daemon[1321]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::a800:4ff:fe00:a04.

Sep 26 17:06:47 X58A-UD3R avahi-daemon[1321]: New relevant interface eth0.IPv6 for mDNS.

Sep 26 17:06:47 X58A-UD3R avahi-daemon[1321]: Registering new address record for fe80::a800:4ff:fe00:a04 on eth0.*.

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Auto-activating connection 'Wired'.

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) starting connection 'Wired'

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> (eth0): device state change: disconnected -> prepare (reason 'none') [30 40 0]

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) scheduled...

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) started...

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) scheduled...

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) complete.

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) starting...

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> (eth0): device state change: prepare -> config (reason 'none') [40 50 0]

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) successful.

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) scheduled.

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) complete.

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) started...

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> (eth0): device state change: config -> ip-config (reason 'none') [50 70 0]

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 4 of 5 (IP4 Configure Get) scheduled...

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Beginning IP6 addrconf.

Sep 26 17:06:50 X58A-UD3R avahi-daemon[1321]: Withdrawing address record for fe80::a800:4ff:fe00:a04 on eth0.

Sep 26 17:06:50 X58A-UD3R avahi-daemon[1321]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::a800:4ff:fe00:a04.

Sep 26 17:06:50 X58A-UD3R avahi-daemon[1321]: Interface eth0.IPv6 no longer relevant for mDNS.

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) complete.

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 4 of 5 (IP4 Configure Get) started...

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Activation (eth0) Stage 5 of 5 (IP Configure Commit) started...

Sep 26 17:06:50 X58A-UD3R avahi-daemon[1321]: Joining mDNS multicast group on interface eth0.IPv4 with address 10.42.43.1.

Sep 26 17:06:50 X58A-UD3R avahi-daemon[1321]: New relevant interface eth0.IPv4 for mDNS.

Sep 26 17:06:50 X58A-UD3R avahi-daemon[1321]: Registering new address record for 10.42.43.1 on eth0.IPv4.

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> caught signal 15, shutting down normally.

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Clearing nscd hosts cache.

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --insert INPUT --in-interface eth0 --protocol tcp --destination-port 53 --jump ACCEPT

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --insert INPUT --in-interface eth0 --protocol udp --destination-port 53 --jump ACCEPT

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --insert INPUT --in-interface eth0 --protocol tcp --destination-port 67 --jump ACCEPT

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --insert INPUT --in-interface eth0 --protocol udp --destination-port 67 --jump ACCEPT

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --insert FORWARD --in-interface eth0 --jump REJECT

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --insert FORWARD --out-interface eth0 --jump REJECT

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --insert FORWARD --in-interface eth0 --out-interface eth0 --jump ACCEPT

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --insert FORWARD --source 10.42.43.0/255.255.255.0 --in-interface eth0 --jump ACCEPT

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table filter --insert FORWARD --destination 10.42.43.0/255.255.255.0 --out-interface eth0 --match state --state ESTABLISHED,RELATED --jump ACCEPT

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Executing: /sbin/iptables --table nat --insert POSTROUTING --source 10.42.43.0/255.255.255.0 ! --destination 10.42.43.0/255.255.255.0 --jump MASQUERADE

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> Starting dnsmasq...

Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]: <info> (eth0): device state change: ip-config -> activated (reason 'none') [70 100 0]

Sep 26 17:06:50 X58A-UD3R dnsmasq[15064]: failed to create listening socket for 10.42.43.1: Address already in use

Sep 26 17:06:50 X58A-UD3R dnsmasq[15064]: FAILED to start up