[Touch-packages] [Bug 2042587] [NEW] jammy's version breaks existing dhcp scripts with relay
Public bug reported: When upgrading from focal to jammy, existing dnsmasq dhcp-scripts stopped working in an environment where a DHCP relay is in use. Instead of the expected client IP address, the script gets the _relay_ IP address as an argument. From dnsmasq documentation for --dhcp-script: > The arguments to the process are "add", "old" or "del", the MAC address of the host (or DUID for IPv6) , the IP address, and the hostname, if known. I believe the change has been inadverently made in upstream commit 527c3c7d0d3bb4bf5fad699f10cf0d1a45a54692 (https://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=blobdiff;f=src/helper.c;h=02340a01c00031db0cc682c8a4a279cfc1db574e;hp=d81de9622e6d484a264496b2cd3638b4e15e9677;hb=527c3c7d0d3bb4bf5fad699f10cf0d1a45a54692;hpb=fcb4dcaf7cc8a86ac2533b933161b6455f75bf8f) as the commit message only speaks about inet_ntoa replacement and not the behavioral change it also introduces (previously the relay address was only set to the environment variable, now it effectively overrides the prevoiusly set client's IP address). dnsmasq 2.86-1.1ubuntu0.3 / Ubuntu 22.04 ** Affects: dnsmasq (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to dnsmasq in Ubuntu. https://bugs.launchpad.net/bugs/2042587 Title: jammy's version breaks existing dhcp scripts with relay Status in dnsmasq package in Ubuntu: New Bug description: When upgrading from focal to jammy, existing dnsmasq dhcp-scripts stopped working in an environment where a DHCP relay is in use. Instead of the expected client IP address, the script gets the _relay_ IP address as an argument. From dnsmasq documentation for --dhcp- script: > The arguments to the process are "add", "old" or "del", the MAC address of the host (or DUID for IPv6) , the IP address, and the hostname, if known. I believe the change has been inadverently made in upstream commit 527c3c7d0d3bb4bf5fad699f10cf0d1a45a54692 (https://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=blobdiff;f=src/helper.c;h=02340a01c00031db0cc682c8a4a279cfc1db574e;hp=d81de9622e6d484a264496b2cd3638b4e15e9677;hb=527c3c7d0d3bb4bf5fad699f10cf0d1a45a54692;hpb=fcb4dcaf7cc8a86ac2533b933161b6455f75bf8f) as the commit message only speaks about inet_ntoa replacement and not the behavioral change it also introduces (previously the relay address was only set to the environment variable, now it effectively overrides the prevoiusly set client's IP address). dnsmasq 2.86-1.1ubuntu0.3 / Ubuntu 22.04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/dnsmasq/+bug/2042587/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 2042587] Re: jammy's version breaks existing dhcp scripts with relay
I'm so sorry this is so complex, but I couldn't figure out any simpler way to reproduce as they components involved do network configuration. Anyway, please find attached a docker compose file and related dnsmasq configurations (mapped automatically in that compose file) that helps in the reproduction by setting up two different dhcp servers based on dnsmasq (focal and jammy) and a machine that can be used to request a dhcp address. To reproduce the bug: 1) first install everything needed by running docker-compose up -d 2) wait until everything has been installed, check for example that the output of has something from all 3 containers and is not getting any more lines docker-compose logs --follow 3) stop jammy version of the server with docker-compose stop jammy-server 4) get inside client machine to run dhclient. Run it first without fake relay address, then with one (to trigger the DHCP relay behaviour in dnsmasq) docker-compose exec client bash dhclient -d -v (ctrl-c after a while) dhclient -d -v -g 192.168.0.10 (ctrl-c after a while) 5) observe server's log dnsmasq-script-sample-focal-server-1 | dnsmasq-dhcp: DHCPREQUEST(eth0) 192.168.0.3 02:42:c0:a8:00:04 dnsmasq-script-sample-focal-server-1 | dnsmasq-dhcp: DHCPACK(eth0) 192.168.0.3 02:42:c0:a8:00:04 5a49beb3cd53 dnsmasq-script-sample-focal-server-1 | hello from dhcp hook script, IP argument is 192.168.0.3 dnsmasq-script-sample-focal-server-1 | dnsmasq-dhcp: DHCPREQUEST(eth0) 192.168.0.3 02:42:c0:a8:00:04 dnsmasq-script-sample-focal-server-1 | dnsmasq-dhcp: DHCPACK(eth0) 192.168.0.3 02:42:c0:a8:00:04 5a49beb3cd53 dnsmasq-script-sample-focal-server-1 | hello from dhcp hook script, IP argument is 192.168.0.3 6) now stop focal version of server and start jammy: docker-compose stop focal-server docker-compose start jammy-server 7) repeat steps 5 and 6, this time the output has the wroing ip in the 2nd hook script invocation dnsmasq-script-sample-jammy-server-1 | dnsmasq-dhcp: DHCPREQUEST(eth0) 192.168.0.1 02:42:c0:a8:00:04 dnsmasq-script-sample-jammy-server-1 | dnsmasq-dhcp: DHCPACK(eth0) 192.168.0.1 02:42:c0:a8:00:04 5a49beb3cd53 dnsmasq-script-sample-jammy-server-1 | hello from dhcp hook script, IP argument is 192.168.0.1 dnsmasq-script-sample-jammy-server-1 | dnsmasq-dhcp: DHCPREQUEST(eth0) 192.168.0.1 02:42:c0:a8:00:04 dnsmasq-script-sample-jammy-server-1 | dnsmasq-dhcp: DHCPACK(eth0) 192.168.0.1 02:42:c0:a8:00:04 5a49beb3cd53 dnsmasq-script-sample-jammy-server-1 | hello from dhcp hook script, IP argument is 192.168.0.10 ** Attachment added: "archive containing docker-compose.yml and needed configuration files" https://bugs.launchpad.net/ubuntu/+source/dnsmasq/+bug/2042587/+attachment/5716459/+files/sample.tar.gz -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to dnsmasq in Ubuntu. https://bugs.launchpad.net/bugs/2042587 Title: jammy's version breaks existing dhcp scripts with relay Status in dnsmasq package in Ubuntu: Incomplete Bug description: When upgrading from focal to jammy, existing dnsmasq dhcp-scripts stopped working in an environment where a DHCP relay is in use. Instead of the expected client IP address, the script gets the _relay_ IP address as an argument. From dnsmasq documentation for --dhcp- script: > The arguments to the process are "add", "old" or "del", the MAC address of the host (or DUID for IPv6) , the IP address, and the hostname, if known. I believe the change has been inadverently made in upstream commit 527c3c7d0d3bb4bf5fad699f10cf0d1a45a54692 (https://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=blobdiff;f=src/helper.c;h=02340a01c00031db0cc682c8a4a279cfc1db574e;hp=d81de9622e6d484a264496b2cd3638b4e15e9677;hb=527c3c7d0d3bb4bf5fad699f10cf0d1a45a54692;hpb=fcb4dcaf7cc8a86ac2533b933161b6455f75bf8f) as the commit message only speaks about inet_ntoa replacement and not the behavioral change it also introduces (previously the relay address was only set to the environment variable, now it effectively overrides the prevoiusly set client's IP address). dnsmasq 2.86-1.1ubuntu0.3 / Ubuntu 22.04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/dnsmasq/+bug/2042587/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 2042587] Re: jammy's version breaks existing dhcp scripts with relay
..also, apologies for all the typos I managed to place there. Step 7 was meant to say "repeat steps 4 and 5" -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to dnsmasq in Ubuntu. https://bugs.launchpad.net/bugs/2042587 Title: jammy's version breaks existing dhcp scripts with relay Status in dnsmasq package in Ubuntu: Incomplete Bug description: When upgrading from focal to jammy, existing dnsmasq dhcp-scripts stopped working in an environment where a DHCP relay is in use. Instead of the expected client IP address, the script gets the _relay_ IP address as an argument. From dnsmasq documentation for --dhcp- script: > The arguments to the process are "add", "old" or "del", the MAC address of the host (or DUID for IPv6) , the IP address, and the hostname, if known. I believe the change has been inadverently made in upstream commit 527c3c7d0d3bb4bf5fad699f10cf0d1a45a54692 (https://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=blobdiff;f=src/helper.c;h=02340a01c00031db0cc682c8a4a279cfc1db574e;hp=d81de9622e6d484a264496b2cd3638b4e15e9677;hb=527c3c7d0d3bb4bf5fad699f10cf0d1a45a54692;hpb=fcb4dcaf7cc8a86ac2533b933161b6455f75bf8f) as the commit message only speaks about inet_ntoa replacement and not the behavioral change it also introduces (previously the relay address was only set to the environment variable, now it effectively overrides the prevoiusly set client's IP address). dnsmasq 2.86-1.1ubuntu0.3 / Ubuntu 22.04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/dnsmasq/+bug/2042587/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 2042587] Re: jammy's version breaks existing dhcp scripts with relay
Hello, and thank you, seems to fix the issue. I updated my jammy's to dsnmasq version 2.86-1.1ubuntu0.5, and tested with the same setup as I reported the original bug. Can confirm that the DHCP hook script now works exatly like it used to in focal, getting the correct IP address as an argument. ** Tags removed: verification-needed-jammy ** Tags added: verification-done-jammy -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to dnsmasq in Ubuntu. https://bugs.launchpad.net/bugs/2042587 Title: jammy's version breaks existing dhcp scripts with relay Status in dnsmasq package in Ubuntu: Fix Released Status in dnsmasq source package in Jammy: Fix Committed Bug description: [ Impact ] When upgrading from focal to jammy, existing dnsmasq dhcp-scripts stopped working in an environment where a DHCP relay is in use. Instead of the expected client IP address, the script gets the _relay_ IP address as an argument. This was fixed in 2.87, therefore making only jammy carry an affected package. [ Test Plan ] To easily test this on a single machine, a test script is being provided to setup networking and dnsmasq configuration. # Launch a jammy VM lxc launch ubuntu-daily:jammy j-dnsmasq-2042587 --vm # open a root shell in that VM. All subsequent commands must be executed as root in that VM lxc shell j-dnsmasq-2042587 # download test script wget https://bugs.launchpad.net/ubuntu/+source/dnsmasq/+bug/2042587/+attachment/5738174/+files/setup- and-server.sh # make it executable chmod +x setup-and-server.sh # install dnsmasq. Ignore the postinst error (because systemd-resolved is also running and there is a port conflict) apt update && apt install dnsmasq -y # run the setup script. It will configure things and start dnsmasq ready to be tested ./setup-and-server.sh # in another root session inside the vm (so run "lxc shell j-dnsmasq-2042587" in another terminal), run the proposed commands from the setup script (and press ctrl-c after the result is shown): No DHCP relay: ip netns exec client dhclient -d -v p2 The setup script should log an IP that is not a relay. For example: dnsmasq-dhcp: DHCPDISCOVER(p1) aa:a0:9d:00:5b:d6 dnsmasq-dhcp: DHCPOFFER(p1) 192.168.47.150 aa:a0:9d:00:5b:d6 dnsmasq-dhcp: DHCPREQUEST(p1) 192.168.47.150 aa:a0:9d:00:5b:d6 dnsmasq-dhcp: DHCPACK(p1) 192.168.47.150 aa:a0:9d:00:5b:d6 j-dnsmasq-2042587 ### IP = 192.168.47.150 ### With DHCP relay set to 192.168.47.9, IP should NOT be that address: ip netns exec client dhclient -d -v p2 -g 192.168.47.9 With the affected dnsmasq package, we will see an error: dnsmasq-dhcp: DHCPREQUEST(p1) 192.168.47.150 aa:a0:9d:00:5b:d6 dnsmasq-dhcp: DHCPACK(p1) 192.168.47.150 aa:a0:9d:00:5b:d6 j-dnsmasq-2042587 ### IP = 192.168.47.9 TEST FAILED ### The error is that the obtained IP is that of the dhcp relay (provided via the -g option). With the fixed dnsmasq package, "TEST FAILED" must not appear, and the IP should not be that of the provided dhcp relay. [ Where problems could occur ] If the fix is incorrect, it would mean the dhcp-script would get an incorrect IP again, or perhaps we could have crashes in dnsmasq when dealing with buffers and pointers if the dhcp-script option is in use. This fix was committed upstream a few months after the bug was introduced, so it took a while to be noticed. [ Other Info ] Not at this time. [ Original description ] When upgrading from focal to jammy, existing dnsmasq dhcp-scripts stopped working in an environment where a DHCP relay is in use. Instead of the expected client IP address, the script gets the _relay_ IP address as an argument. From dnsmasq documentation for --dhcp- script: > The arguments to the process are "add", "old" or "del", the MAC address of the host (or DUID for IPv6) , the IP address, and the hostname, if known. I believe the change has been inadverently made in upstream commit 527c3c7d0d3bb4bf5fad699f10cf0d1a45a54692 (https://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=blobdiff;f=src/helper.c;h=02340a01c00031db0cc682c8a4a279cfc1db574e;hp=d81de9622e6d484a264496b2cd3638b4e15e9677;hb=527c3c7d0d3bb4bf5fad699f10cf0d1a45a54692;hpb=fcb4dcaf7cc8a86ac2533b933161b6455f75bf8f) as the commit message only speaks about inet_ntoa replacement and not the behavioral change it also introduces (previously the relay address was only set to the environment variable, now it effectively overrides the prevoiusly set client's IP address). dnsmasq 2.86-1.1ubuntu0.3 / Ubuntu 22.04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/dnsmasq/+bug/2042587/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packag