Public bug reported: When using "/bin/sh" (dash) as a shell for ssh, or just starting /bin/sh in a terminal, when the shell receives a wall message (from another user or root), it just quits.
How to reproduce: - start a terminal (xterm, gnome-terminal, etc), usually starts with bash - from bash run 'sh' command to open a dash shell - start another terminal, and run: echo "foo" | wall - the broadcast message appears on both terminals - in the first terminal you are thrown back to bash, because dash exits I've tried this on Ubuntu 14.04, 16.04, 18.04 (64bits) latest updates and it's happening on all of them. I've also tried with latest dash from git, compiled on Ubuntu 16.04, same problem, that's why I don't think it's dash's problem. Also tried on CentOS 7, there is no problem there. The problem appears this morning (6 February) after updating to latest version of 16.04, 18.04. I also have a box with 16.04 but not the latest updates, and on that box the problem does not happen. If one uses dash as a login shell, and enters on a remote box with SSH for example, the connection can be terminated by another user simply wall'ing a broadcast message (or a system daemon like NUT). This could be taken as a potential security issue. ** Affects: ubuntu Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1814905 Title: dash exits when receiving wall message To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+bug/1814905/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs