The verification of the Stable Release Update for openssh has completed successfully and the package is now being released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.
-- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/2111226 Title: sshd socket activation does not support AF_VSOCK Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Jammy: Fix Released Status in openssh source package in Noble: Fix Released Status in openssh source package in Oracular: Won't Fix Status in openssh source package in Plucky: Fix Released Status in openssh source package in Questing: Fix Released Bug description: [Impact] On Ubuntu VMs running under Microsoft Hyper-V, users commonly rely on 'hv_sock' (Hyper-V socket) to enable seamless SSH access using the 'hvc.exe' tool on the Windows host. This works correctly on Ubuntu Jammy and earlier, but fails silently in Noble, because the logic in Ubuntu's systemd-socket-activation.patch silently rejects sockets that are not AF_INET or AF_INET6. Hence, when an AF_VSOCK socket is passed (which is supported by systemd socket's ListenStream=), the client connection silently hangs. [Test Case] The autopkgtests for openssh contain socket-activation tests to help avoid regressions in the existing logic. In addition to those tests, the below manual testing will be performed to verify the AF_VSOCK fix: Hyper-V: 1. Launch a VM on Hyper-V, and ensure the hv_sock module is loaded: $ lsmod | grep hv_sock 2. Adding the socket conf for SSH to listen on vsock: $ mkdir -p /etc/systemd/system/ssh.socket.d/ $ cat > /etc/systemd/system/ssh.socket.d/vsock.conf << EOF [Socket] ListenStream=vsock::22 EOF $ systemctl daemon-reload $ systemctl restart ssh.socket 3. Attempt to connect from the Hyper-V host: hvc ssh user@ubuntu-vm Expected Result: Connection succeeds and SSH login is presented. Actual Result: The connection hangs. Other methods: Alternatively, this can be verified using LXD VMs. $ lxc launch --vm ubuntu:$series test $ lxc shell test In the VM: $ mkdir -p /etc/systemd/system/ssh.socket.d/ $ cat > /etc/systemd/system/ssh.socket.d/vsock.conf << EOF [Socket] ListenStream=vsock::22 EOF $ systemctl daemon-reload $ systemctl restart ssh.socket Then, from the host: $ ssh -o StrictHostKeyChecking=no -o "ProxyCommand socat - VSOCK- CONNECT:$VSOCK_CID:22" ubuntu@localhost or, if new enough to have systemd-ssh-proxy $ ssh vsock/$VSOCK_CID [Where problems could occur] The effective goals of the patch are to (a) accept when AF_VSOCK sockets are passed by systemd, and (b) to close() (rather than silently ignore) unsupported socket types. There is additional logic to properly log about where the server is listening. This creates additional room for error. All of the changes are contained within the setup_systemd_socket() function. Therefore, problems would be seen when sshd is socket- activated, e.g. on the first connection attempt to a given server. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/openssh/+bug/2111226/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
