The plot thickens. The configuration of the build appears to be partially implicated. Could it be that with your ./configure flags, it's failing to find a failing PAM or something?
When I build with the ./configure that you suggested, it works. When I build with dpkg-buildpackage, on the same source code, it fails. Output from the failing case, with your patch to add debug output, attached as sshd-strace-20171026.txt ** Attachment added: "sshd-strace-20171026.txt" https://bugs.launchpad.net/ubuntu/+source/openssh/+bug/1690485/+attachment/4997275/+files/sshd-strace-20171026.txt -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1690485 Title: openssh-server SIGSYS with 'UsePrivilegeSeparation sandbox' To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/openssh/+bug/1690485/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs